An effective electrocatalyst being highly active in all pH range for oxygen reduction reaction(ORR)is crucial for energy conversion and storage devices.However,most of the high-efficiency ORR catalysis was reported in...An effective electrocatalyst being highly active in all pH range for oxygen reduction reaction(ORR)is crucial for energy conversion and storage devices.However,most of the high-efficiency ORR catalysis was reported in alkaline conditions.Herein,we demonstrated the preparation of atomically dispersed Fe-Zn pairs anchored on porous N-doped carbon frameworks(Fe-Zn-SA/NC),which works efficiently as ORR catalyst in the whole pH range.It achieves high half-wave potentials of 0.78,0.85 and 0.72 V in 0.1 M HClO4,0.1 M KOH and 0.1 M phosphate buffer saline(PBS)solutions,respectively,as well as respectable stability.The performances are even comparable to Pt/C.Furthermore,when assembled into a Zn-air battery,the high power density of 167.2 mWcm−2 and 120 h durability reveal the feasibility of Fe-Zn-SA/NC in real energy-related devices.Theoretical calculations demonstrate that the superior catalytic activity of Fe-Zn-SA/NC can be contributed to the lower energy barriers of ORR at the Fe-Zn-N6 centers.This work demonstrates the potential of Fe-Zn pairs as alternatives to the Pt catalysts for efficient catalytic ORR and provides new insights of dual-atom catalysts for other energy conversion related catalytic reactions.展开更多
Given the inherent potential of seawater,industrial wastewater,and residential water as inherent feedstocks for hydrogen production through water electrolysis,there is a critical demand for the exploration of robust a...Given the inherent potential of seawater,industrial wastewater,and residential water as inherent feedstocks for hydrogen production through water electrolysis,there is a critical demand for the exploration of robust and stable hydrogen-evolving catalysts that can operate effectively across a diverse range of pH conditions.However,the pursuit of hydrogen-evolving electrocatalysts that demonstrate both good stability and high efficiency over a wide pH range remains a formidable challenge.Here we report the rational design and synthesis of an outstanding nanoporous hybrid electrocatalyst consisting of intermetallic cobalt-molybdenum alloy particles anchoring on MoO2 cuboid arrays,which demands very low overpotentials of 72,123 and 134 mV to deliver a current density of−100 mA·cm^(−2)for hydrogen evolution reaction under alkaline,neutral and acidic conditions,respectively.These catalytic activities are superior to most non-precious-metal-based catalysts documented in the literatures,and are even comparable to noble metal catalysts.In particular,this alloy electrocatalyst exhibits excellent stability at 50 or 300 mA·cm^(−2)without obvious activity degradation,which is further supported by the undetectable changes in the surface chemical valence states on the basis of in-situ X-ray photoelectron spectroscopic studies.This study provides an innovative strategy for the design and synthesis of effective non-noble intermetallic catalysts for pH-universal hydrogen evolution over a wide pH range.展开更多
Developing efficient pH-universal hydrogen evolution reaction(HER)catalysts is critical in the field of water electrolysis,however,which is severely hampered by the sluggish kinetics in alkaline media.Herein,a rutheni...Developing efficient pH-universal hydrogen evolution reaction(HER)catalysts is critical in the field of water electrolysis,however,which is severely hampered by the sluggish kinetics in alkaline media.Herein,a ruthenium(Ru)incorporation induced vacancy engineering strategy is firstly proposed to precisely construct oxygen vacancy(V_(O))-riched cobalt-ruthenium metaphosphate(CRPO)for high-efficiency pH-universal HER.The V_(O) modifies the electronic structure,improves the superficial hydrophilic and gas spillover capacity,it also reduces the coordination number of Ru atoms and regulates the coordination environment.Theoretical calculations indicate that Ru tends to adsorb H_(2)O and H^(*),whereas V_(O) tends to adsorb OH^(-),which greatly promotes the H_(2)O adsorption and the dissociation of HO-H bond.Ultimately,CRPO-2 exhibits remarkable HER performance,the mass activity is about 18.34,21.73,and 38.07 times higher than that of Pt/C in acidic,neutral,and alkaline media,respectively,at the same time maintain excellent stability.Our findings may pave a new avenue for the rational design of electrocatalysts toward pH-universal water electrolysis.展开更多
Rational design of highly active transition-metal phosphides for electrocatalyzing overall water splitting in a wide pH range assisted by first-principle calculations can efficiently save the developing cost and hence...Rational design of highly active transition-metal phosphides for electrocatalyzing overall water splitting in a wide pH range assisted by first-principle calculations can efficiently save the developing cost and hence is quite attractive.Under the guidance of density-functional theory(DFT)calculations that the introduction of dopants(Fe,Mn,and Ni)into CoP could promote the hydrogen evolution reaction(HER)performances,a series of binder-free CoM_(x)P/carbon cloth(CC;M=Fe,Mn,and Ni;x=0,0.05,0.2,0.5,and 1)were fabricated.Both experimental measurements and DFT calculations confirm the electronic modulation of dopants.DFT calculations further reveal that the modulated electronic structure promotes the electronic conductivity,favors the adsorption of key species,and consequently promotes the electrochemical performances.As predicted,the bimetallic phosphides demonstrate excellent HER performances in alkaline,acidic,and alkaline simulated seawater solutions and also deliver excellent oxygen evolution reaction(OER)performances,overwhelming the commercial RuO_(2).Benefiting from the modulated electronic structure and the hierarchical structure with massive CoFe0.05P zero-dimensional(0D)quantum dots anchored on two-dimensional(2D)N-doped porous carbon,CoFe0.05P delivered the best HER in four kinds of electrolytes(ƞ10 of 73 mV in an alkaline simulated seawater solution)and OER in two kinds of electrolytes(ƞ10 of 264 mV in an alkaline solution)with excellent stability of 45 h in the alkaline solution.The assembled CoFe0.05P/CC//CoFe0.05P/CC with the electrodes folded by 180°can still maintain a low cell potential of 1.62 V at 10 mA·cm^(−2).This work proves the feasibility of the reported rational design strategy of developing efficient electrocatalysts for overall water splitting in a wide pH range.展开更多
Hydrogen economy based on electrochemical water splitting exemplified one of the most promising means for overcoming the rapid consumption of fossil fuels and the serious deterioration of global climate.The developmen...Hydrogen economy based on electrochemical water splitting exemplified one of the most promising means for overcoming the rapid consumption of fossil fuels and the serious deterioration of global climate.The development of earth-abundant,efficient,and durable electrocatalysts for hydrogen evolution reaction(HER)plays a vital role in the commercialization of water electrolysis.Regard,the self-supported electrode with unique nitrogen-doped reduced graphene oxide(N-rGO)nanoflakes and WS_(2) hierarchical nanoflower that were grown directly on carbon cloth(CC)substrate(WS_(2)/N-rGO/CC)was successfully synthesized using a facile dual-step hydrothermal approach.The as-synthesized 50%1T/2H-WS_(2)/N-rGO/CC(WGC),which possessed high metallic 1T phase of 57%not only efficiently exposed more active sites and accelerated mass/charge diffusion,but also endowed excellent structural lustiness,robust stability,and durability at a high current density.As a result,the 50%WGC exhibited lower overpotentials and Tafel slopes of 21.13 mV(29.55 mV∙dec^(-1))and 80.35 mV(137.02 mV∙dec^(-1))as compared to 20%Pt-C/CC,respectively for catalyzing acidic and alkaline hydrogen evolution reactions.Pivotally,the as-synthesized 50%WGC also depicted long-term stability for more than 8 h in the high-current-density regions(100 and 220 mA∙cm^(-2)).In brief,this work reveals a self-supported electrode as an extraordinary alternative to Pt-based catalysts for HER in a wide pH range,while paving a facile strategy to develop advanced electrocatalysts with abundant heterointerfaces for practical applications in energy-saving hydrogen production.展开更多
The widespread application of phenolic substances in the field of food,medicine and industry,is harmful to the environment and human health.Therefore,it is very important to develop a con-venient and effective method ...The widespread application of phenolic substances in the field of food,medicine and industry,is harmful to the environment and human health.Therefore,it is very important to develop a con-venient and effective method to detect and degrade phenolic compounds.Herein,we report a new keggin-type polyoxometallate-based metal-organic complex self-assembled under solvothermal condition,{[Cu(dap)(3-PA)]4(SiW_(12)O_(40))(H_(2)O)_(2)}·2H_(2)O(1,dap=1,2-diaminopropane,3-HPA=3-pyridineacrylic acid).1 shows an interesting 1D ladder-like structure.As a bifunctional catalyst,1 can be employed as a colori-metric sensor toward phenol with the relatively low detection limit(LOD)of 0.36μmol/L(S/N=3)in the wide range(0.001-0.1 mmol/L).The title colorimetric sensor is applied to determine phenol in various water environment with good recoveries ranging from 95%-105%.In addition,1 also exhibits excellent photocatalytic degradation toward phenol under visible light with the highest removal efficiency at 96%for 100 min and wide pH universality.The selectivity,stability and reliability of the detection of 1 towards phenol,as well as the detection for 4-chlorophenol,o-cresol,4-nitrophenol and phloroglucinol were stud-ied.Furthermore,the photocatalytic reaction kinetics and the mechanisms of photodegradation of phenol were also investigated in detail.展开更多
The design of high-efficiency non-noble and earth-abundant electrocatalysts for hydrogen evolution reaction(HER)is highly paramount for water splitting and renewable energy systems.Molybdenum disulfide(MoS_(2))with ab...The design of high-efficiency non-noble and earth-abundant electrocatalysts for hydrogen evolution reaction(HER)is highly paramount for water splitting and renewable energy systems.Molybdenum disulfide(MoS_(2))with abundant edge sites can be utilized as a promising alternative,but its catalytic activity is greatly related to the pH values,especially in an alkaline environment due to the extremely high energy barriers for water adsorption and dissociation steps.Here we report an exceptionally efficient and stable electrocatalyst to improve the sluggish HER process of layered MoS_(2)particles in different pH electrolytes,especially in base.The electrocatalyst is constructed by in situ growing selenium-doped MoS_(2)(Se-MoS_(2))nanoparticles on three-dimensional cobalt nickel diselenide(mCo_(0.2)Ni_(0.8)Se_(2))nanostructured arrays.Due to the large number of active edge sites of Se-MoS_(2)particles exposed at the surface,robust electrical conductivity and large surface area of mCo_(0.2)Ni_(0.8)Se_(2)support,and strong interfacial interactions between Se-MoS_(2)and mCo_(0.2)Ni_(0.8)Se_(2),this hybrid catalyst shows very outstanding catalytic HER properties featured by low overpotentials of 30 and 122 mV at 10 and 100 mA/cm^(2)with good operational stability in base,respectively,which outperforms most of inexpensive catalysts consisting of layered MoS_(2),transition metal selenides and sulfides,and it performs as well as noble Pt catalysts.Meanwhile,this electrocatalyst is also very active in neutral and acidic electrolytes,requiring low overpotentials of 93 and 94 mV at 10 mA/cm^(2),respectively,demonstrating its superb pH universality as a HER electrocatalyst with excellent catalytic durability.This study provides a straightforward strategy to construct an efficient non-noble electrocatalyst for driving the HER kinetics in different electrolytes.展开更多
Herein,the merits of heterojunction,CeO_(2),and W are employed to design and prepare the PtCoW@CeO_(2)heterojunction catalyst,which can accelerate water dissociation and improve the desorption of OHad,displaying effic...Herein,the merits of heterojunction,CeO_(2),and W are employed to design and prepare the PtCoW@CeO_(2)heterojunction catalyst,which can accelerate water dissociation and improve the desorption of OHad,displaying efficient hydrogen evolution reaction(HER)performance in pH-universal conditions.Density functional theory calculation results reveal that the electronic structure of Pt is regulated by CeO_(2)and W,which tunes the Pt-Hadbond strength to boost HER intrinsic activity.Consequently,electrochemical results display that it has low potentials of-26,-25,and-23 mV at-10 mA cm^(-2)in alkaline,neutral,and acidic solutions,respectively,and it can stably cycle for 50,000 cycles.Thus,this work provides the guidance for developing high-performance Pt-based catalysts in pH-universal environments.展开更多
Electrocatalyst designs based on oxophilic foreign atoms are considered a promising approach for developing efficient pH-universal hydrogen evolution reaction(HER)electrocatalysts by overcoming the sluggish alkaline H...Electrocatalyst designs based on oxophilic foreign atoms are considered a promising approach for developing efficient pH-universal hydrogen evolution reaction(HER)electrocatalysts by overcoming the sluggish alkaline HER kinetics.Here,we design ternary transition metals-based nickel telluride(Mo WNi Te)catalysts consisting of high valence non-3d Mo and W metals and oxophilic Te as a first demonstration of non-precious heterogeneous electrocatalysts following the bifunctional mechanism.The Mo WNi Te showed excellent HER catalytic performance with overpotentials of 72,125,and 182 mV to reach the current densities of 10,100,and 1000 mA cm^(-2),respectively,and the corresponding Tafel slope of 47,52,and 58 mV dec-1in alkaline media,which is much superior to commercial Pt/C.Additionally,the HER performance of Mo WNi Te is well maintained up to 3000 h at the current density of 100 mA cm^(-2).It is further demonstrated that the Mo WNi Te exhibits remarkable HER activities with an overpotential of 45 mV(31 mV)and Tafel slope of 60 mV dec-1(34 mV dec-1)at 10 mA cm^(-2)in neutral(acid)media.The superior HER performance of Mo WNi Te is attributed to the electronic structure modulation,inducing highly active low valence states by the incorporation of high valence non-3d transition metals.It is also attributed to the oxophilic effect of Te,accelerating water dissociation kinetics through a bifunctional catalytic mechanism in alkaline media.Density functional theory calculations further reveal that such synergistic effects lead to reduced free energy for an efficient water dissociation process,resulting in remarkable HER catalytic performances within universal pH environments.展开更多
Designing highly active and stable noble-metal-free electrocatalysts for water splitting over a wide pH range is critical yet remains significantly challenging.In this work,Mo-doped CoP nanoparticles(Mo-CoP)supported ...Designing highly active and stable noble-metal-free electrocatalysts for water splitting over a wide pH range is critical yet remains significantly challenging.In this work,Mo-doped CoP nanoparticles(Mo-CoP)supported and enwrapped by porous single-atomic-Co doped carbon framework(Co-N-C)were designed and prepared by a simple one-pot pyrolysis method.The Mo-CoP/Co-N-C electrocatalyst exhibits superior performance with low overpotentials of only 45 mV for hydrogen evolution reaction(HER)and 201 mV for oxygen evolution reaction(OER)in 1 M KOH at 10 mA cm^(-2)current density.Such excellent catalytic activity can be ascribed to enhanced intrinsic activity,large surface area,and highly exposed active sites.Meanwhile,an extremely small overpotential of only 250 mV is required for a large current density of 500 mA cm^(-2)in HER,which exceeds the performance of benchmark 10%Pt/C.Besides,Mo-CoP/Co-N-C also exhibits superior HER performance in acidic and neutral mediums,with overpotentials of only 41 and 98 mV in 0.5 M H_(2)SO_(4),and 1 M PBS,respectively,thus achieving efficient water splitting at a wide pH range.The long-term stabilities are guaranteed with no significant decline of catalytic activities for more than 24 h in all electrolytes,which can be ascribed to the carbon layer encapsulation structure.Addition-ally,in overall water splitting,the electrocatalytic cell consisting of the as-synthesized Mo-CoP/Co-N-C only requires a cell voltage of 1.611 V at 100 mA cm^(-2)with excellent stability,exceeding that of the benchmark Pt/C||RuO(2) couple(1.645 V at 100 mA cm^(-2)).This work not only presents a highly efficient electrocatalyst for pH-universal water splitting but also provides a new perspective for the design and construction of transition metal catalysts with excellent stability.展开更多
Both the adsorption/dissociation of water molecules and hydrogen intermediate(H*)are the major limitations to hydrogen evolution reaction(HER).Herein,the modulation of electronic structure and geometric configuration ...Both the adsorption/dissociation of water molecules and hydrogen intermediate(H*)are the major limitations to hydrogen evolution reaction(HER).Herein,the modulation of electronic structure and geometric configuration are combined to design onedimensional electrocatalyst with outstanding HER activity in a wide pH range.The catalyst was composed of molybdenum trioxide doped molybdenum nickel alloy supported by copper nanowires(MoO_(3)-MoNi_(4)@Cu NWs).As revealed by the experimental characterizations and theoretical calculations,Cu NWs act as the electron donator to MoNi4,resulting in up shift of the d-band center in MoNi4,thus expediting H_(2)O adsorption and dissociation.Moreover,the introduction of amorphous MoO_(3) sets up a unique geometric configuration on MoNi4 for the accelerated H*transfer via hydrogen-bond and hydrogen spillover.This work provides a synergetic route for constructing HER freeway and promotes further investigations on more versatile electrocatalysis involving H_(2)O or H*.展开更多
Designing synergistic heterogeneous catalytic interfaces is the key to developing highly compatible pH-universal electrocatalysts for complex chemical environments.Our theoretical calculation results demonstrate that ...Designing synergistic heterogeneous catalytic interfaces is the key to developing highly compatible pH-universal electrocatalysts for complex chemical environments.Our theoretical calculation results demonstrate that the Ru-Ru2P heterointerface can not only promote the redistribution of charges,but also reduce the d-band center,and then enhances the adsorption capacity of the key intermediate.However,in situ and facile synthesis of Ru-Ru2P heterostructures is severely limited by thermodynamic obstacles.Herein,we propose a molten salt-assisted catalytic synthesis scheme,and successfully build a series of homologous metallic Ru-Ru2P heterostructure catalysts with different molar ratios of Ru to P under atmospheric pressure and low-temperature(400C).The resultant Ru-Ru2P with rich heterostructures show the Pt-like HER performance in different pH media.Particularly,it is prominent under alkaline conditions(18 mV@10 mA cm^(2)),which outperforms the Pt catalyst(37 mV@10 mA cm^(2)).Furthermore,Ru-Ru2P heterostructures also show certain potential in the electrolysis of seawater to produce hydrogen.This work represents a significant supplement of high-efficiency pH-universal HER catalysts,and provides a new light on interface engineering in energy technology fields and beyond.展开更多
With practical electrocatalytic hydrogen production frequently involving the splitting of water in various pH media,there is an urgent need but still a technical challenge to develop low-cost,highly active,and stable ...With practical electrocatalytic hydrogen production frequently involving the splitting of water in various pH media,there is an urgent need but still a technical challenge to develop low-cost,highly active,and stable electrocatalysts for pH-universal hydrogen evolution reaction(HER).We report herein the adoption of a hydrothermal reaction combined with a post gas-phase doping strategy to fabricate P-doped NiCo_(2)Se_(4) hollow nanoneedle arrays on carbon fiber paper(i.e.,P-NiCo_(2)Se_(4)/CFP).Notably,the optimal arrays(P8.71-NiCo_(2)Se_(4)/CFP)can afford an outstanding pH-universal HER performance,with an overpotential as low as 33,57,and 69 mV at 10 mA·cm^(−2) and corresponding Tafel slopes down to 52,61,and 72 mV·dec^(−1) in acidic,alkaline,and neutral media,respectively,outperforming most state-of-the-art nonprecious catalysts and even the commercial Pt/C catalyst in both neutral and alkaline media at large current densities.Impressively,P_(8.71-)NiCo_(2)Se_(4)/CFP also displays good durability toward long-time stability testing in harsh acidic and alkaline electrolytes.Experimental and theoretical studies further reveal that the doping of P atoms into NiCo_(2)Se_(4) can simultaneously optimize its H*adsorption/desorption energy,water adsorption energy,and water dissociation energy by adjusting the local electronic states of various active sites,thus accelerating the rate-determining step of HER in different pH media to endow P-NiCo_(2)Se_(4) with an outstanding pH-universal HER performance.This work provides atomic-level insights into the roles of active sites in various electrolysis environments,thereby shedding new light on the rational design of highly efficient pH-universal nonprecious catalysts for HER and beyond.展开更多
Developing efficient and stable electrocatalyst to hydrogen evolution reaction adaptable for electrolytes with different p H is a big challenge.In this work,a hierarchically structured ternary nanohybrid composed of f...Developing efficient and stable electrocatalyst to hydrogen evolution reaction adaptable for electrolytes with different p H is a big challenge.In this work,a hierarchically structured ternary nanohybrid composed of flower-like Ru nanoparticles,rigid macrocyclic cucurbit[6]uril(CB[6])and carboxylated multiwalled carbon nanotubes(MWCNTs)was successfully prepared by chemical wet method.Benefited by the structural merits of flower-like Ru nanoparticles exposed abundant active sites supported by the MWCNTs holding superior mass transport and electrons transfer ability as well as the existence of CB[6],the obtained catalyst exhibited outstanding HER activities with overpotentials of 27,37 and 70 m V at-10 m A/cm^(2) in alkaline,acidic,and neutral electrolytes,respectively.Under the same electrocatalytic operation conditions,the HER performance is comparable or superior to commercial Pt/C catalyst(47,27and 49 m V).Besides,chronopotentiometric and accelerated stability test also revealed its extraordinary stability,which could be further employed for electrocatalytic procedure in a broad pH range.展开更多
Hydrogen is one of the most promising energy carriers to replace fossil fuels and electrolyzing water to produce hydrogen is a very effective method.However,designing highly active and stable non-precious metal hydrog...Hydrogen is one of the most promising energy carriers to replace fossil fuels and electrolyzing water to produce hydrogen is a very effective method.However,designing highly active and stable non-precious metal hydrogen evolution electrocatalysts that can be used in universal pH is a huge challenge.Here,we have reported a simple strategy to develop a highly active and durable non-precious MoO2-Ni electrocatalyst for hydrogen evolution reaction(HER)in a wide pH range.The MoO2-Ni catalyst exhibits a superior electrocatalytic performance with low overpotentials of 46,69,and 84 mV to reach-10 mA cm-2 in 1.0 M KOH,0.5 M H2SO4,and 1.0 M PBS electrolytes,respectively.At the same time,the catalyst also shows outstanding stability over a wide pH range.It is particularly noted that the catalytic performance of MoO2-Ni in alkaline solution is comparable to the highest performing catalysts reported.The outstanding HER performance is mainly attributed to the collective effect of the rational morphological design,electronic structure engineering,and strong interfacial coupling between MoO2 and Ni in heterojunctions.This work provides a viable method for the synthesis of inexpensive and efficient HER electrocatalysts for the use in wide pH ranges.展开更多
The study of atomically dispersed metal-nitrogen electrocatalysts is still limited in terms of understanding their catalytic mechanism because of the inability to precisely regulate the coordination number and type of...The study of atomically dispersed metal-nitrogen electrocatalysts is still limited in terms of understanding their catalytic mechanism because of the inability to precisely regulate the coordination number and type of N in combination with the metal elements.Inspired by the high catalytic activity and selectivity of natural enzymes,herein,we have designed and fabricated ultrathin carbon nanosheet-supported Mn single-atom catalysts(SACs)with a precise pyrrole-type Mn-N4(PT-MnN4)configuration using a bio-mimicking strategy.The PT-MnN4 SACs display outstanding oxygen reduction reaction(ORR)activity,with a half-wave potential(E_(1/2))of 0.88 V(vs.revisible hydrogen electrode[RHE])and extremely high stability in alkaline media.Moreover,superior ORR activities are also obtained,E_(1/2) of 0.73 V and 0.63 V in acid and neutral electrolytes,respectively,indicating the efficient pH-universal ORR performances.The assembled zinc-air battery using the PT-MnN4 SACs as air cathodes exhibits a high peak power density(175 mW cm^(−2))and long-term stability up to 150 h,implying its promising application in metal-air batteries.This study has paved the way toward the rational design and precise regulation of single-atom electrocatalysts.展开更多
Herein,a simple synthetic approach is employed for the atomic dispersion of Rh atoms(Rh SAs)over the surface of interconnected Mo_(2)C nanosheets intimately embedded in a three-dimensional Ni_(x)MoO_(y)nanorod arrays(...Herein,a simple synthetic approach is employed for the atomic dispersion of Rh atoms(Rh SAs)over the surface of interconnected Mo_(2)C nanosheets intimately embedded in a three-dimensional Ni_(x)MoO_(y)nanorod arrays(Ni_(x)MoO_(y)NRs)framework;we found that the introduction of both isolated Rh SAs and Ni_(x)MoO_(y)NRs adjusts the electrocatalytic function of the host Mo_(2)C toward the direction of being an advanced and highly stable electrocatalyst for efficient hydrogen evolution at pH-universal conditions.As a result,the proposed catalyst outperforms most recently reported transition metal-based catalysts,and its performance even rivals that of commercial Pt/C,as demonstrated by its ultralow overpotentials of 31.7,109.7,and 95.4 mV at a current density of 10 mA cm^(-2),along with its small Tafel slopes of 42.4,51.2,and 46.8 mV dec^(-1)in acidic,neutral,and alkaline conditions,respectively.In addition,the catalyst shows remarkable long-term stability over all pH values with good maintenance of its catalytic activity and structural characteristics after continuous operation.展开更多
Production of hydrogen(H2) and oxygen(O2) through electrocatalytic water splitting is one of the sustainable,green and pivotal ways to accomplish the ever-increasing demands for renewable energy sources,but remains a ...Production of hydrogen(H2) and oxygen(O2) through electrocatalytic water splitting is one of the sustainable,green and pivotal ways to accomplish the ever-increasing demands for renewable energy sources,but remains a big challenge because of the uphill reaction during overall water splitting.Herein,we develop high-performance non-noble metal electrocatalysts for pH-universal water splitting,based on nickel/vanadium boride(NiVB) nanoparticles/reduced graphene oxide(rGO) hybrid(NiVB/rGO)through a facile chemical reduction approach under ambient condition.By virtue of more exposure to surface active sites,superior electron transfer capability and strong electronic coupling,the asprepared NiVB/rGO heterostructure needs pretty low overpotentials of 267 and 151 mV to deliver a current density of 10 mA cm^(-2) for oxygen evolution reaction(OER) and hydrogen evolution reaction(HER)respectively,with the corresponding Tafel slope of 44 and 88 mV dec^(-1) in 1.0 M KOH.Moreover,the NiVB/rGO electrocatalysts display a promising performance in a wide-pH conditions that require low overpotential of 310,353 and 489 mV to drive a current density of 10 mA cm^(-2) for OER under 0.5 M KOH,0.05 M H2SO4 and 1.0 M phosphate buffer solution(PBS) respectively,confirming the excellent electrocata lytic performance among state-of-the-art Ni-based electrocatalysts for overall water splitting.Therefore,the interfacial tuning based on incorporation of active heterostructure may pave a new route to develop bifunctional,cost-effective and efficient electrocatalyst systems for water splitting and H2 production.展开更多
Rational design and construction of low-cost and highly efficient electrocatalysts for hydrogen evolution reaction(HER)is meaningful but challenging.Herein,a robust three dimensional(3D)hollow CoSe_(2)@ultrathin MoSe_...Rational design and construction of low-cost and highly efficient electrocatalysts for hydrogen evolution reaction(HER)is meaningful but challenging.Herein,a robust three dimensional(3D)hollow CoSe_(2)@ultrathin MoSe_(2)core@shell heterostructure(CoSe_(2)@MoSe_(2))is proposed as an efficient HER electrocatalyst through interfacial engineering.Benefitting from the abundant heterogeneous interfaces on CoSe_(2)@MoSe_(2),the exposed edge active sites are maximized and the charge transfer at the hetero-interfaces is accelerated,thus facilitating the HER kinetics.It exhibits remarkable performance in pH-universal conditions.Notably,it only needs an overpotential(η10)of 108 mV to reach a current density of 10 mA·cm^(-2)in 1.0 M KOH,outperforming most of the reported transition metal selenides electrocatalysts.Density functional theory(DFT)calculations unveil that the heterointerfaces synergistically optimize the Gibbs free energies of H2O and H^(*)during alkaline HER,accelerating the reaction kinetics.The present work may provide new construction guidance for rational design of high-efficient electrocatalysts.展开更多
Ruthenium(Ru)is one of the most promising metals for its versatility in driving a wide range of catalytic reactions.However,owing to the intrinsic preference of hexagonal close-packed(hcp)phase for bulk Ru,currently,i...Ruthenium(Ru)is one of the most promising metals for its versatility in driving a wide range of catalytic reactions.However,owing to the intrinsic preference of hexagonal close-packed(hcp)phase for bulk Ru,currently,it is still challenging to construct Ru-based nanomaterials with face-centered-cubic(fcc)phase for optimizing their performance towards potential applications.Herein,we report a facile wet-chemical method to directly create unconventional fcc-structured Ru-copper hollow urchin-like nanospheres(fcc-RuCu HUNSs)as a class of efficient pH-universal hydrogen evolution reaction(HER)electrocatalyst.Interestingly,this synthetic strategy can be expanded to prepare other fcc-Ru-based alloy nanomaterials.Significantly,the novel fcc-RuCu HUNSs exhibit superior HER performance with the overpotential of only 25,34,40,and 26 m V to reach the current density of 10 mA cm^(-2)in 0.5 M H_(2)SO_(4),0.05 M H_(2)SO_(4),0.1 M KOH,and 1 M KOH,respectively,much lower than those of hcpRuCu HUNSs and commercial Pt/C.Density functional theory(DFT)calculations further indicate that their excellent pH-universal HER performance results from the optimized adsorption free energy of H and work functions.Our work highlights the importance of phase control to design high-efficiency nanocatalysts for relevant catalytic reactions in energy conversion.展开更多
基金This work was financially supported by National Key R&D Program of China(No.2017YFA0700104)the National Natural Science Foundation of China(Nos.22075211,21601136,51971157,51761165012,and 62005173)+2 种基金Project funded by China Postdoctoral Science Foundation(No.2020TQ0201)Tianjin Science Fund for Distinguished Young Scholars(No.19JCJQJC61800)The authors also acknowledge National Supercomputing Center in Shenzhen for providing the computational resources and materials studio(version 7.0,DMol3).
文摘An effective electrocatalyst being highly active in all pH range for oxygen reduction reaction(ORR)is crucial for energy conversion and storage devices.However,most of the high-efficiency ORR catalysis was reported in alkaline conditions.Herein,we demonstrated the preparation of atomically dispersed Fe-Zn pairs anchored on porous N-doped carbon frameworks(Fe-Zn-SA/NC),which works efficiently as ORR catalyst in the whole pH range.It achieves high half-wave potentials of 0.78,0.85 and 0.72 V in 0.1 M HClO4,0.1 M KOH and 0.1 M phosphate buffer saline(PBS)solutions,respectively,as well as respectable stability.The performances are even comparable to Pt/C.Furthermore,when assembled into a Zn-air battery,the high power density of 167.2 mWcm−2 and 120 h durability reveal the feasibility of Fe-Zn-SA/NC in real energy-related devices.Theoretical calculations demonstrate that the superior catalytic activity of Fe-Zn-SA/NC can be contributed to the lower energy barriers of ORR at the Fe-Zn-N6 centers.This work demonstrates the potential of Fe-Zn pairs as alternatives to the Pt catalysts for efficient catalytic ORR and provides new insights of dual-atom catalysts for other energy conversion related catalytic reactions.
基金supported by the funding projects from the National Natural Science Foundation of China(Nos.52172197 and 22309051)the Youth 1000 Talent Program of China,Major Projects“Takes the lead”of Natural Science Foundation(No.2021JC0008)of Hunan ProvinceInterdisciplinary Research Program(No.2023JC201)of Hunan Normal University in Changsha,China.
文摘Given the inherent potential of seawater,industrial wastewater,and residential water as inherent feedstocks for hydrogen production through water electrolysis,there is a critical demand for the exploration of robust and stable hydrogen-evolving catalysts that can operate effectively across a diverse range of pH conditions.However,the pursuit of hydrogen-evolving electrocatalysts that demonstrate both good stability and high efficiency over a wide pH range remains a formidable challenge.Here we report the rational design and synthesis of an outstanding nanoporous hybrid electrocatalyst consisting of intermetallic cobalt-molybdenum alloy particles anchoring on MoO2 cuboid arrays,which demands very low overpotentials of 72,123 and 134 mV to deliver a current density of−100 mA·cm^(−2)for hydrogen evolution reaction under alkaline,neutral and acidic conditions,respectively.These catalytic activities are superior to most non-precious-metal-based catalysts documented in the literatures,and are even comparable to noble metal catalysts.In particular,this alloy electrocatalyst exhibits excellent stability at 50 or 300 mA·cm^(−2)without obvious activity degradation,which is further supported by the undetectable changes in the surface chemical valence states on the basis of in-situ X-ray photoelectron spectroscopic studies.This study provides an innovative strategy for the design and synthesis of effective non-noble intermetallic catalysts for pH-universal hydrogen evolution over a wide pH range.
基金supported by National Natural Science Foundation of China(Nos.21721003,22202080,22034006).
文摘Developing efficient pH-universal hydrogen evolution reaction(HER)catalysts is critical in the field of water electrolysis,however,which is severely hampered by the sluggish kinetics in alkaline media.Herein,a ruthenium(Ru)incorporation induced vacancy engineering strategy is firstly proposed to precisely construct oxygen vacancy(V_(O))-riched cobalt-ruthenium metaphosphate(CRPO)for high-efficiency pH-universal HER.The V_(O) modifies the electronic structure,improves the superficial hydrophilic and gas spillover capacity,it also reduces the coordination number of Ru atoms and regulates the coordination environment.Theoretical calculations indicate that Ru tends to adsorb H_(2)O and H^(*),whereas V_(O) tends to adsorb OH^(-),which greatly promotes the H_(2)O adsorption and the dissociation of HO-H bond.Ultimately,CRPO-2 exhibits remarkable HER performance,the mass activity is about 18.34,21.73,and 38.07 times higher than that of Pt/C in acidic,neutral,and alkaline media,respectively,at the same time maintain excellent stability.Our findings may pave a new avenue for the rational design of electrocatalysts toward pH-universal water electrolysis.
基金supported by the National Key Research and Development Program of China(No.2019YFB1311605)the National Natural Science Foundation of China(No.21703137)the Shanghai Sailing Program(No.20YF1416100).
文摘Rational design of highly active transition-metal phosphides for electrocatalyzing overall water splitting in a wide pH range assisted by first-principle calculations can efficiently save the developing cost and hence is quite attractive.Under the guidance of density-functional theory(DFT)calculations that the introduction of dopants(Fe,Mn,and Ni)into CoP could promote the hydrogen evolution reaction(HER)performances,a series of binder-free CoM_(x)P/carbon cloth(CC;M=Fe,Mn,and Ni;x=0,0.05,0.2,0.5,and 1)were fabricated.Both experimental measurements and DFT calculations confirm the electronic modulation of dopants.DFT calculations further reveal that the modulated electronic structure promotes the electronic conductivity,favors the adsorption of key species,and consequently promotes the electrochemical performances.As predicted,the bimetallic phosphides demonstrate excellent HER performances in alkaline,acidic,and alkaline simulated seawater solutions and also deliver excellent oxygen evolution reaction(OER)performances,overwhelming the commercial RuO_(2).Benefiting from the modulated electronic structure and the hierarchical structure with massive CoFe0.05P zero-dimensional(0D)quantum dots anchored on two-dimensional(2D)N-doped porous carbon,CoFe0.05P delivered the best HER in four kinds of electrolytes(ƞ10 of 73 mV in an alkaline simulated seawater solution)and OER in two kinds of electrolytes(ƞ10 of 264 mV in an alkaline solution)with excellent stability of 45 h in the alkaline solution.The assembled CoFe0.05P/CC//CoFe0.05P/CC with the electrodes folded by 180°can still maintain a low cell potential of 1.62 V at 10 mA·cm^(−2).This work proves the feasibility of the reported rational design strategy of developing efficient electrocatalysts for overall water splitting in a wide pH range.
基金supports provided by the National Natural Science Foundation of China(No.22202168)the Guangdong Basic and Applied Basic Research Foundation(No.2021A1515111019)+2 种基金This work was also funded by the Xiamen University Malaysia Investigatorship Grant(No.IENG/0038)the Xiamen University Malaysia Research Fund(Nos.ICOE/0001,XMUMRF/2021-C8/IENG/0041,and XMUMRF/2019-C3/IENG/0013)the Hengyuan International Sdn.Bhd.(No.EENG/0003).
文摘Hydrogen economy based on electrochemical water splitting exemplified one of the most promising means for overcoming the rapid consumption of fossil fuels and the serious deterioration of global climate.The development of earth-abundant,efficient,and durable electrocatalysts for hydrogen evolution reaction(HER)plays a vital role in the commercialization of water electrolysis.Regard,the self-supported electrode with unique nitrogen-doped reduced graphene oxide(N-rGO)nanoflakes and WS_(2) hierarchical nanoflower that were grown directly on carbon cloth(CC)substrate(WS_(2)/N-rGO/CC)was successfully synthesized using a facile dual-step hydrothermal approach.The as-synthesized 50%1T/2H-WS_(2)/N-rGO/CC(WGC),which possessed high metallic 1T phase of 57%not only efficiently exposed more active sites and accelerated mass/charge diffusion,but also endowed excellent structural lustiness,robust stability,and durability at a high current density.As a result,the 50%WGC exhibited lower overpotentials and Tafel slopes of 21.13 mV(29.55 mV∙dec^(-1))and 80.35 mV(137.02 mV∙dec^(-1))as compared to 20%Pt-C/CC,respectively for catalyzing acidic and alkaline hydrogen evolution reactions.Pivotally,the as-synthesized 50%WGC also depicted long-term stability for more than 8 h in the high-current-density regions(100 and 220 mA∙cm^(-2)).In brief,this work reveals a self-supported electrode as an extraordinary alternative to Pt-based catalysts for HER in a wide pH range,while paving a facile strategy to develop advanced electrocatalysts with abundant heterointerfaces for practical applications in energy-saving hydrogen production.
基金supported by the National Natural Science Foundation of China(NSFC,Nos.21901018,21971024,22271021)the Natural Science Foundation and Education Department of Liaoning province(Nos.2022-MS-373,2021-MS-312,LJ2020008).
文摘The widespread application of phenolic substances in the field of food,medicine and industry,is harmful to the environment and human health.Therefore,it is very important to develop a con-venient and effective method to detect and degrade phenolic compounds.Herein,we report a new keggin-type polyoxometallate-based metal-organic complex self-assembled under solvothermal condition,{[Cu(dap)(3-PA)]4(SiW_(12)O_(40))(H_(2)O)_(2)}·2H_(2)O(1,dap=1,2-diaminopropane,3-HPA=3-pyridineacrylic acid).1 shows an interesting 1D ladder-like structure.As a bifunctional catalyst,1 can be employed as a colori-metric sensor toward phenol with the relatively low detection limit(LOD)of 0.36μmol/L(S/N=3)in the wide range(0.001-0.1 mmol/L).The title colorimetric sensor is applied to determine phenol in various water environment with good recoveries ranging from 95%-105%.In addition,1 also exhibits excellent photocatalytic degradation toward phenol under visible light with the highest removal efficiency at 96%for 100 min and wide pH universality.The selectivity,stability and reliability of the detection of 1 towards phenol,as well as the detection for 4-chlorophenol,o-cresol,4-nitrophenol and phloroglucinol were stud-ied.Furthermore,the photocatalytic reaction kinetics and the mechanisms of photodegradation of phenol were also investigated in detail.
基金This project has been partially supported by THE Science and Technology Innovation Platform(Nos.2018RS3070,2019RS1032)Hundred Youth Talents Programs of Hunan Province,and the'XiaoXiang Scholar'Talents Foundation of Hunan Normal Univer-sity in Changsha of P.R.China+2 种基金This project also acknowledges the supports from the Postgraduate Scientific Research Innovation Project of Hunan Province(No.CX20200519)instrumental analy-sis funds provided by Hunan Normal University(20CSY095,20CSY096)the National Science Foundation of China(Nos.11704109,51801059).
文摘The design of high-efficiency non-noble and earth-abundant electrocatalysts for hydrogen evolution reaction(HER)is highly paramount for water splitting and renewable energy systems.Molybdenum disulfide(MoS_(2))with abundant edge sites can be utilized as a promising alternative,but its catalytic activity is greatly related to the pH values,especially in an alkaline environment due to the extremely high energy barriers for water adsorption and dissociation steps.Here we report an exceptionally efficient and stable electrocatalyst to improve the sluggish HER process of layered MoS_(2)particles in different pH electrolytes,especially in base.The electrocatalyst is constructed by in situ growing selenium-doped MoS_(2)(Se-MoS_(2))nanoparticles on three-dimensional cobalt nickel diselenide(mCo_(0.2)Ni_(0.8)Se_(2))nanostructured arrays.Due to the large number of active edge sites of Se-MoS_(2)particles exposed at the surface,robust electrical conductivity and large surface area of mCo_(0.2)Ni_(0.8)Se_(2)support,and strong interfacial interactions between Se-MoS_(2)and mCo_(0.2)Ni_(0.8)Se_(2),this hybrid catalyst shows very outstanding catalytic HER properties featured by low overpotentials of 30 and 122 mV at 10 and 100 mA/cm^(2)with good operational stability in base,respectively,which outperforms most of inexpensive catalysts consisting of layered MoS_(2),transition metal selenides and sulfides,and it performs as well as noble Pt catalysts.Meanwhile,this electrocatalyst is also very active in neutral and acidic electrolytes,requiring low overpotentials of 93 and 94 mV at 10 mA/cm^(2),respectively,demonstrating its superb pH universality as a HER electrocatalyst with excellent catalytic durability.This study provides a straightforward strategy to construct an efficient non-noble electrocatalyst for driving the HER kinetics in different electrolytes.
基金supported by the National Natural Science Foundation of China(22162004)the Excellent Scholars and Innovation Team of Guangxi Universities,the Innovation Project of Guangxi Graduate Education(YCBZ2022038)the High-performance Computing Platform of Guangxi University。
文摘Herein,the merits of heterojunction,CeO_(2),and W are employed to design and prepare the PtCoW@CeO_(2)heterojunction catalyst,which can accelerate water dissociation and improve the desorption of OHad,displaying efficient hydrogen evolution reaction(HER)performance in pH-universal conditions.Density functional theory calculation results reveal that the electronic structure of Pt is regulated by CeO_(2)and W,which tunes the Pt-Hadbond strength to boost HER intrinsic activity.Consequently,electrochemical results display that it has low potentials of-26,-25,and-23 mV at-10 mA cm^(-2)in alkaline,neutral,and acidic solutions,respectively,and it can stably cycle for 50,000 cycles.Thus,this work provides the guidance for developing high-performance Pt-based catalysts in pH-universal environments.
基金supported through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(2022M3H4A1A04096478)the support from the Supercomputing Center of Wuhan University。
文摘Electrocatalyst designs based on oxophilic foreign atoms are considered a promising approach for developing efficient pH-universal hydrogen evolution reaction(HER)electrocatalysts by overcoming the sluggish alkaline HER kinetics.Here,we design ternary transition metals-based nickel telluride(Mo WNi Te)catalysts consisting of high valence non-3d Mo and W metals and oxophilic Te as a first demonstration of non-precious heterogeneous electrocatalysts following the bifunctional mechanism.The Mo WNi Te showed excellent HER catalytic performance with overpotentials of 72,125,and 182 mV to reach the current densities of 10,100,and 1000 mA cm^(-2),respectively,and the corresponding Tafel slope of 47,52,and 58 mV dec-1in alkaline media,which is much superior to commercial Pt/C.Additionally,the HER performance of Mo WNi Te is well maintained up to 3000 h at the current density of 100 mA cm^(-2).It is further demonstrated that the Mo WNi Te exhibits remarkable HER activities with an overpotential of 45 mV(31 mV)and Tafel slope of 60 mV dec-1(34 mV dec-1)at 10 mA cm^(-2)in neutral(acid)media.The superior HER performance of Mo WNi Te is attributed to the electronic structure modulation,inducing highly active low valence states by the incorporation of high valence non-3d transition metals.It is also attributed to the oxophilic effect of Te,accelerating water dissociation kinetics through a bifunctional catalytic mechanism in alkaline media.Density functional theory calculations further reveal that such synergistic effects lead to reduced free energy for an efficient water dissociation process,resulting in remarkable HER catalytic performances within universal pH environments.
基金The authors gratefully thank the National Natural Science Foun-dation of China(Nos.22278431 and 21776302)for the financial support of this work.
文摘Designing highly active and stable noble-metal-free electrocatalysts for water splitting over a wide pH range is critical yet remains significantly challenging.In this work,Mo-doped CoP nanoparticles(Mo-CoP)supported and enwrapped by porous single-atomic-Co doped carbon framework(Co-N-C)were designed and prepared by a simple one-pot pyrolysis method.The Mo-CoP/Co-N-C electrocatalyst exhibits superior performance with low overpotentials of only 45 mV for hydrogen evolution reaction(HER)and 201 mV for oxygen evolution reaction(OER)in 1 M KOH at 10 mA cm^(-2)current density.Such excellent catalytic activity can be ascribed to enhanced intrinsic activity,large surface area,and highly exposed active sites.Meanwhile,an extremely small overpotential of only 250 mV is required for a large current density of 500 mA cm^(-2)in HER,which exceeds the performance of benchmark 10%Pt/C.Besides,Mo-CoP/Co-N-C also exhibits superior HER performance in acidic and neutral mediums,with overpotentials of only 41 and 98 mV in 0.5 M H_(2)SO_(4),and 1 M PBS,respectively,thus achieving efficient water splitting at a wide pH range.The long-term stabilities are guaranteed with no significant decline of catalytic activities for more than 24 h in all electrolytes,which can be ascribed to the carbon layer encapsulation structure.Addition-ally,in overall water splitting,the electrocatalytic cell consisting of the as-synthesized Mo-CoP/Co-N-C only requires a cell voltage of 1.611 V at 100 mA cm^(-2)with excellent stability,exceeding that of the benchmark Pt/C||RuO(2) couple(1.645 V at 100 mA cm^(-2)).This work not only presents a highly efficient electrocatalyst for pH-universal water splitting but also provides a new perspective for the design and construction of transition metal catalysts with excellent stability.
基金the National Natural Science Foundation of China(No.22101300)the Shandong Natural Science Foundation(Nos.ZR2020ME053,ZR2020QB027,and ZR2022ME105)+2 种基金State Key Laboratory of Enhanced Oil Recovery of Open Fund Funded Project(No.2022-KFKT-28)Major Special Projects of China National Petroleum Corporation(No.2021ZZ01-05)the Fundamental Research Funds for the Central Universities(Nos.22CX03010A,20CX06007A,and 22CX01002A-1).
文摘Both the adsorption/dissociation of water molecules and hydrogen intermediate(H*)are the major limitations to hydrogen evolution reaction(HER).Herein,the modulation of electronic structure and geometric configuration are combined to design onedimensional electrocatalyst with outstanding HER activity in a wide pH range.The catalyst was composed of molybdenum trioxide doped molybdenum nickel alloy supported by copper nanowires(MoO_(3)-MoNi_(4)@Cu NWs).As revealed by the experimental characterizations and theoretical calculations,Cu NWs act as the electron donator to MoNi4,resulting in up shift of the d-band center in MoNi4,thus expediting H_(2)O adsorption and dissociation.Moreover,the introduction of amorphous MoO_(3) sets up a unique geometric configuration on MoNi4 for the accelerated H*transfer via hydrogen-bond and hydrogen spillover.This work provides a synergetic route for constructing HER freeway and promotes further investigations on more versatile electrocatalysis involving H_(2)O or H*.
基金National Natural Science Foundation of China,Grant/Award Numbers:22075223,22179104State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology),Grant/Award Number:2021-ZD-4。
文摘Designing synergistic heterogeneous catalytic interfaces is the key to developing highly compatible pH-universal electrocatalysts for complex chemical environments.Our theoretical calculation results demonstrate that the Ru-Ru2P heterointerface can not only promote the redistribution of charges,but also reduce the d-band center,and then enhances the adsorption capacity of the key intermediate.However,in situ and facile synthesis of Ru-Ru2P heterostructures is severely limited by thermodynamic obstacles.Herein,we propose a molten salt-assisted catalytic synthesis scheme,and successfully build a series of homologous metallic Ru-Ru2P heterostructure catalysts with different molar ratios of Ru to P under atmospheric pressure and low-temperature(400C).The resultant Ru-Ru2P with rich heterostructures show the Pt-like HER performance in different pH media.Particularly,it is prominent under alkaline conditions(18 mV@10 mA cm^(2)),which outperforms the Pt catalyst(37 mV@10 mA cm^(2)).Furthermore,Ru-Ru2P heterostructures also show certain potential in the electrolysis of seawater to produce hydrogen.This work represents a significant supplement of high-efficiency pH-universal HER catalysts,and provides a new light on interface engineering in energy technology fields and beyond.
基金supported by the National Natural Science Foundation of China(Nos.21872011 and 21273020).
文摘With practical electrocatalytic hydrogen production frequently involving the splitting of water in various pH media,there is an urgent need but still a technical challenge to develop low-cost,highly active,and stable electrocatalysts for pH-universal hydrogen evolution reaction(HER).We report herein the adoption of a hydrothermal reaction combined with a post gas-phase doping strategy to fabricate P-doped NiCo_(2)Se_(4) hollow nanoneedle arrays on carbon fiber paper(i.e.,P-NiCo_(2)Se_(4)/CFP).Notably,the optimal arrays(P8.71-NiCo_(2)Se_(4)/CFP)can afford an outstanding pH-universal HER performance,with an overpotential as low as 33,57,and 69 mV at 10 mA·cm^(−2) and corresponding Tafel slopes down to 52,61,and 72 mV·dec^(−1) in acidic,alkaline,and neutral media,respectively,outperforming most state-of-the-art nonprecious catalysts and even the commercial Pt/C catalyst in both neutral and alkaline media at large current densities.Impressively,P_(8.71-)NiCo_(2)Se_(4)/CFP also displays good durability toward long-time stability testing in harsh acidic and alkaline electrolytes.Experimental and theoretical studies further reveal that the doping of P atoms into NiCo_(2)Se_(4) can simultaneously optimize its H*adsorption/desorption energy,water adsorption energy,and water dissociation energy by adjusting the local electronic states of various active sites,thus accelerating the rate-determining step of HER in different pH media to endow P-NiCo_(2)Se_(4) with an outstanding pH-universal HER performance.This work provides atomic-level insights into the roles of active sites in various electrolysis environments,thereby shedding new light on the rational design of highly efficient pH-universal nonprecious catalysts for HER and beyond.
基金the financial support from the National Key R&D Program of China(Nos.2017YFA0206802,2018YFA0704502)the National Natural Science Foundation of China(NSFC,No.22033008)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(No.2021ZZ103)。
文摘Developing efficient and stable electrocatalyst to hydrogen evolution reaction adaptable for electrolytes with different p H is a big challenge.In this work,a hierarchically structured ternary nanohybrid composed of flower-like Ru nanoparticles,rigid macrocyclic cucurbit[6]uril(CB[6])and carboxylated multiwalled carbon nanotubes(MWCNTs)was successfully prepared by chemical wet method.Benefited by the structural merits of flower-like Ru nanoparticles exposed abundant active sites supported by the MWCNTs holding superior mass transport and electrons transfer ability as well as the existence of CB[6],the obtained catalyst exhibited outstanding HER activities with overpotentials of 27,37 and 70 m V at-10 m A/cm^(2) in alkaline,acidic,and neutral electrolytes,respectively.Under the same electrocatalytic operation conditions,the HER performance is comparable or superior to commercial Pt/C catalyst(47,27and 49 m V).Besides,chronopotentiometric and accelerated stability test also revealed its extraordinary stability,which could be further employed for electrocatalytic procedure in a broad pH range.
基金supported by the National Natural Science Foundation of China(21965005)Natural Science Foundation of Guangxi Province(2018GXNSFAA294077 and 2018GXNSFAA281220)Project of High-Level Talents of Guangxi(F-KA18015 and 2018ZD004)。
文摘Hydrogen is one of the most promising energy carriers to replace fossil fuels and electrolyzing water to produce hydrogen is a very effective method.However,designing highly active and stable non-precious metal hydrogen evolution electrocatalysts that can be used in universal pH is a huge challenge.Here,we have reported a simple strategy to develop a highly active and durable non-precious MoO2-Ni electrocatalyst for hydrogen evolution reaction(HER)in a wide pH range.The MoO2-Ni catalyst exhibits a superior electrocatalytic performance with low overpotentials of 46,69,and 84 mV to reach-10 mA cm-2 in 1.0 M KOH,0.5 M H2SO4,and 1.0 M PBS electrolytes,respectively.At the same time,the catalyst also shows outstanding stability over a wide pH range.It is particularly noted that the catalytic performance of MoO2-Ni in alkaline solution is comparable to the highest performing catalysts reported.The outstanding HER performance is mainly attributed to the collective effect of the rational morphological design,electronic structure engineering,and strong interfacial coupling between MoO2 and Ni in heterojunctions.This work provides a viable method for the synthesis of inexpensive and efficient HER electrocatalysts for the use in wide pH ranges.
基金support from the Independent Designing Scientific Research Project of Zhejiang Normal University(2020ZS03)the Zhejiang Provincial Ten Thousand Talent Program(2017R52043)+1 种基金support from the Zhejiang Province Basic Public Welfare Research Project(LGF19B070006)supported by the National Natural Science Foundation of China(No.21775138).
文摘The study of atomically dispersed metal-nitrogen electrocatalysts is still limited in terms of understanding their catalytic mechanism because of the inability to precisely regulate the coordination number and type of N in combination with the metal elements.Inspired by the high catalytic activity and selectivity of natural enzymes,herein,we have designed and fabricated ultrathin carbon nanosheet-supported Mn single-atom catalysts(SACs)with a precise pyrrole-type Mn-N4(PT-MnN4)configuration using a bio-mimicking strategy.The PT-MnN4 SACs display outstanding oxygen reduction reaction(ORR)activity,with a half-wave potential(E_(1/2))of 0.88 V(vs.revisible hydrogen electrode[RHE])and extremely high stability in alkaline media.Moreover,superior ORR activities are also obtained,E_(1/2) of 0.73 V and 0.63 V in acid and neutral electrolytes,respectively,indicating the efficient pH-universal ORR performances.The assembled zinc-air battery using the PT-MnN4 SACs as air cathodes exhibits a high peak power density(175 mW cm^(−2))and long-term stability up to 150 h,implying its promising application in metal-air batteries.This study has paved the way toward the rational design and precise regulation of single-atom electrocatalysts.
基金Supported from the Regional Leading Research Center Program(2019R1A5A8080326)through the National Research Foundation funded by the Ministry of Science and ICT of Republic of Korea.
文摘Herein,a simple synthetic approach is employed for the atomic dispersion of Rh atoms(Rh SAs)over the surface of interconnected Mo_(2)C nanosheets intimately embedded in a three-dimensional Ni_(x)MoO_(y)nanorod arrays(Ni_(x)MoO_(y)NRs)framework;we found that the introduction of both isolated Rh SAs and Ni_(x)MoO_(y)NRs adjusts the electrocatalytic function of the host Mo_(2)C toward the direction of being an advanced and highly stable electrocatalyst for efficient hydrogen evolution at pH-universal conditions.As a result,the proposed catalyst outperforms most recently reported transition metal-based catalysts,and its performance even rivals that of commercial Pt/C,as demonstrated by its ultralow overpotentials of 31.7,109.7,and 95.4 mV at a current density of 10 mA cm^(-2),along with its small Tafel slopes of 42.4,51.2,and 46.8 mV dec^(-1)in acidic,neutral,and alkaline conditions,respectively.In addition,the catalyst shows remarkable long-term stability over all pH values with good maintenance of its catalytic activity and structural characteristics after continuous operation.
基金supported by the National Natural Science Foundation of China(Grant Nos.21771021,21822501,21720303,and 22061130206)the Beijing Municipal Natural Science Foundation(JQ20003)+5 种基金the Newton Advanced Fellowship award(NAF\R1\201285)the Fok Ying-Tong Education Foundation(Grant No.171008)the Beijing Nova Program(Grant No.xx2018115)the State Key Laboratory of Rare Earth Resources UtilizationChangchun Institute of Applied Chemistry,CAS(RERU2019005)the Fundamental Research Funds for the Central Universities and the Measurements Fund of Beijing Normal University。
文摘Production of hydrogen(H2) and oxygen(O2) through electrocatalytic water splitting is one of the sustainable,green and pivotal ways to accomplish the ever-increasing demands for renewable energy sources,but remains a big challenge because of the uphill reaction during overall water splitting.Herein,we develop high-performance non-noble metal electrocatalysts for pH-universal water splitting,based on nickel/vanadium boride(NiVB) nanoparticles/reduced graphene oxide(rGO) hybrid(NiVB/rGO)through a facile chemical reduction approach under ambient condition.By virtue of more exposure to surface active sites,superior electron transfer capability and strong electronic coupling,the asprepared NiVB/rGO heterostructure needs pretty low overpotentials of 267 and 151 mV to deliver a current density of 10 mA cm^(-2) for oxygen evolution reaction(OER) and hydrogen evolution reaction(HER)respectively,with the corresponding Tafel slope of 44 and 88 mV dec^(-1) in 1.0 M KOH.Moreover,the NiVB/rGO electrocatalysts display a promising performance in a wide-pH conditions that require low overpotential of 310,353 and 489 mV to drive a current density of 10 mA cm^(-2) for OER under 0.5 M KOH,0.05 M H2SO4 and 1.0 M phosphate buffer solution(PBS) respectively,confirming the excellent electrocata lytic performance among state-of-the-art Ni-based electrocatalysts for overall water splitting.Therefore,the interfacial tuning based on incorporation of active heterostructure may pave a new route to develop bifunctional,cost-effective and efficient electrocatalyst systems for water splitting and H2 production.
基金The authors thank the National Natural Science Foundation of China(Nos.U1804140,U20041100 and 21801015)for supportThis work is also supported by Beijing Institute of Technology Research Fund Program for Young Scholars(No.3090012221909).
文摘Rational design and construction of low-cost and highly efficient electrocatalysts for hydrogen evolution reaction(HER)is meaningful but challenging.Herein,a robust three dimensional(3D)hollow CoSe_(2)@ultrathin MoSe_(2)core@shell heterostructure(CoSe_(2)@MoSe_(2))is proposed as an efficient HER electrocatalyst through interfacial engineering.Benefitting from the abundant heterogeneous interfaces on CoSe_(2)@MoSe_(2),the exposed edge active sites are maximized and the charge transfer at the hetero-interfaces is accelerated,thus facilitating the HER kinetics.It exhibits remarkable performance in pH-universal conditions.Notably,it only needs an overpotential(η10)of 108 mV to reach a current density of 10 mA·cm^(-2)in 1.0 M KOH,outperforming most of the reported transition metal selenides electrocatalysts.Density functional theory(DFT)calculations unveil that the heterointerfaces synergistically optimize the Gibbs free energies of H2O and H^(*)during alkaline HER,accelerating the reaction kinetics.The present work may provide new construction guidance for rational design of high-efficient electrocatalysts.
基金supported by the Ministry of Science and Technology of China(2017YFA0208200,2016YFA0204100)the National Natural Science Foundation of China(22025108,21902136)+1 种基金the China Postdoctoral Science Foundation(2020M682083)the Start-up Support from Xiamen University。
文摘Ruthenium(Ru)is one of the most promising metals for its versatility in driving a wide range of catalytic reactions.However,owing to the intrinsic preference of hexagonal close-packed(hcp)phase for bulk Ru,currently,it is still challenging to construct Ru-based nanomaterials with face-centered-cubic(fcc)phase for optimizing their performance towards potential applications.Herein,we report a facile wet-chemical method to directly create unconventional fcc-structured Ru-copper hollow urchin-like nanospheres(fcc-RuCu HUNSs)as a class of efficient pH-universal hydrogen evolution reaction(HER)electrocatalyst.Interestingly,this synthetic strategy can be expanded to prepare other fcc-Ru-based alloy nanomaterials.Significantly,the novel fcc-RuCu HUNSs exhibit superior HER performance with the overpotential of only 25,34,40,and 26 m V to reach the current density of 10 mA cm^(-2)in 0.5 M H_(2)SO_(4),0.05 M H_(2)SO_(4),0.1 M KOH,and 1 M KOH,respectively,much lower than those of hcpRuCu HUNSs and commercial Pt/C.Density functional theory(DFT)calculations further indicate that their excellent pH-universal HER performance results from the optimized adsorption free energy of H and work functions.Our work highlights the importance of phase control to design high-efficiency nanocatalysts for relevant catalytic reactions in energy conversion.
