Photocatalytic reduction of CO_(2) into valuable fuels is one of the potential strategies to solve the carbon cycle and energy crisis.Graphitic carbon nitride(g-C_(3)N_(4)),as a typical two-dimensional(2D)semiconducto...Photocatalytic reduction of CO_(2) into valuable fuels is one of the potential strategies to solve the carbon cycle and energy crisis.Graphitic carbon nitride(g-C_(3)N_(4)),as a typical two-dimensional(2D)semiconductor with a bandgap of∼2.7 eV,has attracted wide attention in photocatalytic CO_(2) reduction.However,the performance of g-C_(3)N_(4) is greatly limited by the rapid recombination of photogenerated charge carriers and weak CO_(2) activation capacity.Construction of van der Waals heterostructure with the maximum interface contact area can improve the transfer/seperation efficiency of interface charge carriers.Ultrathin metal antimony(Sb)nanosheet(antimonene)with high carrier mobility and 2D layered structure,is a good candidate material to construct 2D/2D Sb/g-C_(3)N_(4) van der Waals heterostructure.In this work,the density functional theory(DFT)calculations indicated that antimonene has higher carrier mobility than g-C_(3)N_(4) nanosheets.Obvious charge transfer and in-plane structure distortion will occur at the interface of Sb/g-C_(3)N_(4),which endow stronger CO_(2) activation ability on di-coordinated N active site.The ultrathin g-C_(3)N_(4) and antimonene nanosheets were prepared by ultrasonic exfoliation method,and Sb/g-C_(3)N_(4) van der Waals heterostructures were constructed by self-assembly process.The photoluminescence(PL)and time-resolved photoluminescence(TRPL)indicated that the Sb/g-C_(3)N_(4) van der Waals heterostructures have a better photogenerated charge separation efficiency than pure g-C_(3)N_(4) nanosheets.In-situ FTIR spectroscopy demonstrated a stronger ability of CO_(2) activation to^ (∗)COOH on Sb/g-C_(3)N_(4) van der Waals heterostructure.As a result,the Sb/g-C_(3)N_(4) van der Waals heterostructures showed a higher CO yield with 2.03 umol g^(−1) h^(−1),which is 3.2 times that of pure g-C_(3)N_(4).This work provides a reference for activating CO_(2) and promoting CO_(2) reduction by van der Waals heterostructure.展开更多
Reducing the ever-growing level of CO_(2)in the atmosphere is critical for the sustainable development of human society in the context of global warming.Integration of the capture and upgrading of CO_(2)is,therefore,h...Reducing the ever-growing level of CO_(2)in the atmosphere is critical for the sustainable development of human society in the context of global warming.Integration of the capture and upgrading of CO_(2)is,therefore,highly desirable since each process step is costly,both energetically and economically.Here,we report a CO_(2)direct air capture(DAC)and fixation process that produces methane.Low concentrations of CO_(2)(∼400 ppm)in the air are captured by an aqueous solution of sodium hydroxide to form carbonate.The carbonate is subsequently hydrogenated to methane,which is easily separated from the reaction system,catalyzed by TiO2-supported Ru in the aqueous phase with a selectivity of 99.9%among gas-phase products.The concurrent regenerated hydroxide,in turn,increases the alkalinity of the aqueous solution for further CO_(2)capture,thereby enabling this one-ofits-kind continuous CO_(2)capture and methanation process.Engineering simulations demonstrate the energy feasibility of this CO_(2)DAC and methanation process,highlighting its promise for potential largescale applications.展开更多
Diatomic-site catalysts(DASCs)have emerged as a kind of promising heterogeneous candidate catalysts for electrochemical CO_(2)reduction(ECR),which is considered to retain the advantage of single-atom catalysts(SACs)bu...Diatomic-site catalysts(DASCs)have emerged as a kind of promising heterogeneous candidate catalysts for electrochemical CO_(2)reduction(ECR),which is considered to retain the advantage of single-atom catalysts(SACs)but also introduce opportunities to exceed the limit of single-atom catalysts.In the past few years,tremendous progress has been achieved in this field.Herein,the recent progress in ECR on DASCs has been summarized.It will start with the classification of DASCs.Then the challenges in the precise fabrication and characterization of DASCs have been emphasized.By introducing the advanced ECR performance on DASCs,superior to that on SACs,the synergistic effects of the dual metal atoms are highlighted,as this origin of the advanced ECR performance on DASCs is comprehensively summarized.Finally,the major challenges and perspectives of DASCs have been proposed to shed light on the development of DASCs for ECR application.展开更多
In recent years,the dry reforming of methane(DRM)reaction has gained widespread attention due to its effective utilization of two major greenhouse gases.Supported Ni-based catalysts for DRM exhibit a strong dependence...In recent years,the dry reforming of methane(DRM)reaction has gained widespread attention due to its effective utilization of two major greenhouse gases.Supported Ni-based catalysts for DRM exhibit a strong dependence on particle size,however,the reaction mechanisms involved remain unclear.In this work,the effect of metal particle size on CO_(2)activation and CO formation was explored in the DRM reaction using the density functional theory.Nix/MgO(x=13,25,37)was constructed to investigate the CO_(2)activation and the formation of CO during the DRM reaction.It is found that CO_(2)is more inclined to undergo chemisorption on Nix/MgO before activation.With the variation in particle size,the main activation pathway of CO_(2)on the catalyst changes.On the smallest Ni13/MgO,CO_(2)tends to directly dissociate,while on the larger Ni25/MgO and Ni37/MgO,the hydrogenation dissociation of CO_(2)is more kinetically favorable.Compared to Ni13/MgO and Ni37/MgO,the oxidation of surface C atoms and the oxidation of CH occur more readily on Ni25/MgO.This indicates that C atoms are less likely to form on Ni25 particle and are more easily to be oxidized.To some extent,the results suggest that Ni25/MgO exhibits superior resistance to carbon formation.展开更多
Solid oxide electrolysis cells(SOECs)provide a promising way for converting renewable energy into chemical fuels.Traditionally,NiO/CGO(nickel-gadolinium doped ceria)cermet has shown its excellent properties in ionic a...Solid oxide electrolysis cells(SOECs)provide a promising way for converting renewable energy into chemical fuels.Traditionally,NiO/CGO(nickel-gadolinium doped ceria)cermet has shown its excellent properties in ionic and electronic conductivity under reducing conditions.Herein,we developed a novel 1D NiO/CGO cathode through a cerium metal-organic framework(MOF)derived process.The cathode’s 1D nanostructure integrated with a microchannel scaffold facilitates enhanced mass transport,providing vertically aligned pathways for CO_(2)and H_(2)O diffusion.Additionally,the 1D framework increases the number of interfacial sites and reduces ion diffusion distances,thereby simplifying electron/ion transport.Consequently,this advanced cathode achieved a significant breakthrough in SOEC performance,maintaining efficient CO_(2)and H_(2)O electrolysis at an extraordinary current density of 1.41 A/cm^(2)at 1.5 V and excellent stability over 24 h at 850℃.The enhanced performance of this newly developed cathode not only achieves a remarkable 100%improvement compared to those of NiO/CGO cathodes with varying geometrical configurations but also surpasses those of commercial NiO/CGO catalysts by an outstanding 40%when tested under identical conditions.The development of the 1D NiO/CGO enhances the efficiency and durability of ceramic cathodes for CO_(2)and H_(2)O co-electrolysis in SOECs and improves the scalability and effectiveness of SOECs in renewable energy applications.展开更多
The effect of oxygen vacancies on the adsorption and activation of CO_(2) on the surface of different phases of ZrO_(2) is investigated by density functional theory(DFT)calculations.The calculations show that the oxyg...The effect of oxygen vacancies on the adsorption and activation of CO_(2) on the surface of different phases of ZrO_(2) is investigated by density functional theory(DFT)calculations.The calculations show that the oxygen vacancies contribute greatly to both the adsorption and activation of CO_(2).The adsorption energy of CO_(2) on the c-ZrO_(2),t-ZrO_(2) and,m-ZrO_(2) surfaces is enhanced to 5,4,and 3 folds with the help of oxygen vacancies,respectively.Moreover,the energy barrier of CO_(2) dissociation on the defective surfaces of c-ZrO_(2),t-ZrO_(2),and m-ZrO_(2) is reduced to 1/2,1/4,and 1/5 of the perfect surface with the assistance of oxygen vacancies.Furthermore,the activation of CO_(2) on the ZrO_(2) surface where oxygen vacancies are present,and changes from an endothermic reaction to an exothermic reaction.This finding demonstrates that the presence of oxygen vacancies promotes the activation of CO_(2) both kinetically and thermodynamically.These results could provide guidance for the high-efficient utilization of CO_(2) at an atomic scale.展开更多
The capture,storage,and release of CO_(2)is one of the most pressing issues in chemistry.Herein,we designed bis(formazanate)magnesium complexes as precursors,which were synthesized by straightforward transamination be...The capture,storage,and release of CO_(2)is one of the most pressing issues in chemistry.Herein,we designed bis(formazanate)magnesium complexes as precursors,which were synthesized by straightforward transamination between the neutral formazan[PhNNC(4-tBuPh)NNHPh](LH)and[Mg{N(SiMe_(3))_(2)}_(2)].Depending on the solvent,either the homoleptic complex[L_(2)Mg]or the thf-coordinated complex[L_(2)Mg(thf)]was isolated.Reaction of the solvent-free complex[L_(2)Mg]with CO_(2)led to stoichiometric insertion into one of the four Mg–Nbonds with concomitant rearrangement of the ligand scaffold which adopts a trinuclear cagelike structure.The insertion reaction is reversible depending on thermolysis or treatment with tetrahydrofuran,which is corroborated by density functional theory calculations.This showcases the first example of reversible uptake of CO_(2)by an s-block coordination compound.展开更多
In this review,the history and outlook of gas-phase CO_(2)activation using single electrons,metal atoms,clusters(mainly metal hydride clusters),and molecules are discussed on both of the experimental and theoretical f...In this review,the history and outlook of gas-phase CO_(2)activation using single electrons,metal atoms,clusters(mainly metal hydride clusters),and molecules are discussed on both of the experimental and theoretical fronts.Although the development of bulk solid-state materials for the activation and conversion of CO_(2)into value-added products have enjoyed great success in the past several decades,this review focuses only on gas-phase studies,because isolated,well-defined gas-phase systems are ideally suited for high-resolution experiments using state-of-the-art spectrometric and spectroscopic techniques,and for simulations employing modern quantum theoretical methods.The unmatched high complementarity and comparability of experiment and theory in the case of gas-phase investigations bear an enormous potential in providing insights in the reactions of CO_(2)activation at the atomic level.In all of these examples,the reduction and bending of the inert neutral CO_(2)molecule is the critical step determined by the frontier orbitals of reaction participants.Based on the results and outlook summarized in this review,we anticipate that studies of gas-phase CO_(2)activations will be an avenue rich with opportunities for the rational design of novel catalysts based on the knowledge obtained on the atomic level.展开更多
For the first time,this paper demonstrates a synergistic effect from the combination of a gliding arc discharge plasma with a photocatalyst TiO_(2) for CO_(2) dissociation.The effects of adding a tray downstream the d...For the first time,this paper demonstrates a synergistic effect from the combination of a gliding arc discharge plasma with a photocatalyst TiO_(2) for CO_(2) dissociation.The effects of adding a tray downstream the discharge and the combination of the catalyst with plasma have been investigated.Two different combination modes of plasma catalysis,i.e.,in-plasma catalysis and post-plasma catalysis,have been evaluated with the emphasis on the analysis of potential mechanisms.The results show that modifying the gliding arc reactor by the addition of a tray can enhance the fraction of gas treated by plasma,thus improv-ing the reaction performance.An exceptional synergistic effect of combining the gliding arc discharge with TiO_(2) for CO_(2) activation forms in the in-plasma catalysis mode.The presence of TiO_(2) significantly enhances the CO_(2) conversion by 138% and the energy efficiency by 133%at a flow rate of 2 L/min.The plasma activation effect,which produces energetic electrons that can create the electron-hole pairs on the catalyst surface,is believed to be the major contributor to the generation of the plasma catalysis synergy.This mechanism has been further evidenced by the negligible influence of the post-plasma catalysis on the reaction performance.展开更多
Carbon dioxide electroreduction usually suffers from low catalytic activities and debatable reaction mechanisms at present. That may be primarily ascribed to the high energy barrier for carbon dioxide activation over ...Carbon dioxide electroreduction usually suffers from low catalytic activities and debatable reaction mechanisms at present. That may be primarily ascribed to the high energy barrier for carbon dioxide activation over the conventionally fabricated catalysts and the infeasibility of traditional characterization techniques for unveiling the evolution of active sites and reactive intermediates. Two-dimensional(2 D) materials, which possess the active sites with high proportion, high activity and high uniformity, can act as ideal models to manipulate the active sites and understand structure-property relationship. In this review, we overview the boosted carbon dioxide activation by the intrinsic peculiar electronic states of 2D catalysts and the charge localization effect induced by chemical modification of two-dimensional catalysts. We also summarize the recognition of the structural evolutions for active sites in two-dimensional catalysts by means of in situ X-ray diffraction pattern and in situ X-ray absorption spectroscopy. Moreover, we emphasize the detection of the reactive intermediates on active sites in two-dimensional catalysts via in situ Raman spectroscopy and in situ Fourier transform infrared spectroscopy. Finally, we end this review with an outlook on the unresolved issues and future development of carbon dioxide electroreduction.展开更多
To realize efficient atmospheric CO_(2) chemisorption and activation,abundant Ti^(3+) sites and oxygen vacancies in TiO_(2) ultrathin layers were designed.Positron annihilation lifetime spectroscopy and theoretical ca...To realize efficient atmospheric CO_(2) chemisorption and activation,abundant Ti^(3+) sites and oxygen vacancies in TiO_(2) ultrathin layers were designed.Positron annihilation lifetime spectroscopy and theoretical calculations first unveil each oxygen vacancy is associated with the formation of two Ti^(3+)sites,giving a Ti^(3+)-V_(o)-Ti^(3+) configuration.The Ti^(3+)-V_(o)-Ti^(3+) sites could bond with CO_(2) molecules to form a stable configuration,which converted the endoergic chemisorption step to an exoergic process,verified by in-situ Fourier-transform infrared spectra and theoretical calculations.Also,the adjacent Ti^(3+)sites not only favor CO_(2) activation into COOH*via forming a stable Ti^(3+)–C–O–Ti^(3+) configuration,but also facilitate the rate-limiting COOH^(*)scission to CO^(*)by reducing the energy barrier from 0.75 to 0.45 e V.Thus,the Ti^(3+)-V_(o)-TiO_(2) ultrathinlayers could directly capture and photofix atmospheric CO_(2) into near-unity CO,with the corresponding CO_(2)-to-CO conversion ratio of ca.20.2%.展开更多
CO_(2)accumulation is inducing an effect of global warming.Adsorption using solid sorbents is proving as an effective strategy for CO_(2)capture and reuse.The aim of this study was to develop amino-functionalized magn...CO_(2)accumulation is inducing an effect of global warming.Adsorption using solid sorbents is proving as an effective strategy for CO_(2)capture and reuse.The aim of this study was to develop amino-functionalized magnetic nanoparticles by depositing various amines through coprecipitation or impregnation-sonication.Structural characteristics were studied through SEM,BET and XRD analyses,evidencing coarse particles with low crystallinity and surface areas of 100–150 m2 g−1,while FT-IR confirmed CO_(2)interacting with substrate.The load of functional group,particles stability,and CO_(2)sorption capacity were assessed through elemental and thermogravimetric analysis.It was found that loads of functional groups ranging from 1.6 to 6.1 wt.%.were deposited,and most samples showed sound stability up to 100°C.Sorption capacities were in the range 0.2–1.5 g gNH2−1,the highest being 1.46 g gNH2−1 forɛ-aminocaproic acid.Such sample also exhibited good recyclability,with a performance drop of 11%after many cycles.CO_(2)uptake decreased with increasing temperature in the range 25–45°C,suggesting a chemical bond between CO_(2)and amines.Amino functionalized particles could thus be an interesting solution for CO_(2)capture and utilization thanks to fast kinetics,recyclability,and ease of separation.展开更多
Intercalation transition metal oxides (ITMO)have attracted great attention as lithium-ion battery negative electrodes due to high operation safety,high capacity and rapid ion intercalation.However,the intrinsic low el...Intercalation transition metal oxides (ITMO)have attracted great attention as lithium-ion battery negative electrodes due to high operation safety,high capacity and rapid ion intercalation.However,the intrinsic low electron conductivity plagues the lifetime and cell performance of the ITMO negative electrode.Here we design a new carbon-emcoating architecture through single CO_(2)activation treatment as demonstrated by the Nb_(2)O_(5)/C nanohybrid.Triple structure engineering of the carbon-emcoating Nb_(2)O_(5)/C nanohybrid is achieved in terms of porosity,composition,and crystallographic phase.The carbon-embedding Nb_(2)O_(5)/C nanohybrids show superior cycling and rate performance compared with the conventional carbon coating,with reversible capacity of 387 m A h g(-1)at 0.2 C and 92%of capacity retained after 500cycles at 1 C.Differential electrochemical mass spectrometry(DEMS) indicates that the carbon emcoated Nb_(2)O_(5)nanohybrids present less gas evolution than commercial lithium titanate oxide during cycling.The unique carbon-emcoating technique can be universally applied to other ITMO negative electrodes to achieve high electrochemical performance.展开更多
A novel three-dimensional(3D) carbon nanotube foams(CNTF) with ultrahigh specific surface area have been fabricated through a unique but facile one-step synthesis by using CO_2 as both carbon source and activating age...A novel three-dimensional(3D) carbon nanotube foams(CNTF) with ultrahigh specific surface area have been fabricated through a unique but facile one-step synthesis by using CO_2 as both carbon source and activating agent. The activation temperature and time have been adjusted, and the best sample demonstrates a specific surface area of 1959.8 m^2 g^(–1) and a total pore volume of 3.23 cm^3 g^(–1). A reversible capacity of about 870 mAhg^(–1) is maintained at 50 mAg^(–1) when the CNTF used as cathode materials. Meanwhile, the capacity is as large as 320 mAhg^(–1) at the current density of 2 A g^(–1) and the capacity retention is nearly 100% after 500 cycles. These excellent and highly stable battery performances should be attributed to the structural advantages of as-synthesized CNTFs generated by using a facile CO_2-assisted strategy, which may potentially be applied in large scale production of porous 3D carbon materials in the fields of energy storage and conversion.展开更多
基金supported by National Natural Science Foundation of China(Nos.22002189 and 51973078)the Open Project from Key Laboratory of Green and Precise Synthetic Chemistry and Applications(No.2020KF07)+1 种基金the Distinguished Young Scholar of Anhui Province(No.1808085J14)the Key Foundation of Educational Commission of Anhui Province(Nos.KJ2019A0595 and KJ2020ZD005)。
文摘Photocatalytic reduction of CO_(2) into valuable fuels is one of the potential strategies to solve the carbon cycle and energy crisis.Graphitic carbon nitride(g-C_(3)N_(4)),as a typical two-dimensional(2D)semiconductor with a bandgap of∼2.7 eV,has attracted wide attention in photocatalytic CO_(2) reduction.However,the performance of g-C_(3)N_(4) is greatly limited by the rapid recombination of photogenerated charge carriers and weak CO_(2) activation capacity.Construction of van der Waals heterostructure with the maximum interface contact area can improve the transfer/seperation efficiency of interface charge carriers.Ultrathin metal antimony(Sb)nanosheet(antimonene)with high carrier mobility and 2D layered structure,is a good candidate material to construct 2D/2D Sb/g-C_(3)N_(4) van der Waals heterostructure.In this work,the density functional theory(DFT)calculations indicated that antimonene has higher carrier mobility than g-C_(3)N_(4) nanosheets.Obvious charge transfer and in-plane structure distortion will occur at the interface of Sb/g-C_(3)N_(4),which endow stronger CO_(2) activation ability on di-coordinated N active site.The ultrathin g-C_(3)N_(4) and antimonene nanosheets were prepared by ultrasonic exfoliation method,and Sb/g-C_(3)N_(4) van der Waals heterostructures were constructed by self-assembly process.The photoluminescence(PL)and time-resolved photoluminescence(TRPL)indicated that the Sb/g-C_(3)N_(4) van der Waals heterostructures have a better photogenerated charge separation efficiency than pure g-C_(3)N_(4) nanosheets.In-situ FTIR spectroscopy demonstrated a stronger ability of CO_(2) activation to^ (∗)COOH on Sb/g-C_(3)N_(4) van der Waals heterostructure.As a result,the Sb/g-C_(3)N_(4) van der Waals heterostructures showed a higher CO yield with 2.03 umol g^(−1) h^(−1),which is 3.2 times that of pure g-C_(3)N_(4).This work provides a reference for activating CO_(2) and promoting CO_(2) reduction by van der Waals heterostructure.
基金the Natural Science Foundation of China(grant nos.21725301,21932002,21821004,91645115,51872008,22172183,22172150,and 22222306)the National Key R&D Program of China(grant nos.2017YFB060220 and 2021YFA-1502804)+3 种基金the Beijing Outstanding Young Scientists Projects(grant nos.BJJWZYJH01201910005018 and BJJWZYJH01201914430039)the Strategic Priority Research Program of the Chinese Academy of Science(grant no.XDB0450102)the K.C.Wong Education Foundation(grant no.GJTD-2020-15)the Innovation Program for Quantum Science and Technology(grant no.2021ZD0303302).
文摘Reducing the ever-growing level of CO_(2)in the atmosphere is critical for the sustainable development of human society in the context of global warming.Integration of the capture and upgrading of CO_(2)is,therefore,highly desirable since each process step is costly,both energetically and economically.Here,we report a CO_(2)direct air capture(DAC)and fixation process that produces methane.Low concentrations of CO_(2)(∼400 ppm)in the air are captured by an aqueous solution of sodium hydroxide to form carbonate.The carbonate is subsequently hydrogenated to methane,which is easily separated from the reaction system,catalyzed by TiO2-supported Ru in the aqueous phase with a selectivity of 99.9%among gas-phase products.The concurrent regenerated hydroxide,in turn,increases the alkalinity of the aqueous solution for further CO_(2)capture,thereby enabling this one-ofits-kind continuous CO_(2)capture and methanation process.Engineering simulations demonstrate the energy feasibility of this CO_(2)DAC and methanation process,highlighting its promise for potential largescale applications.
基金supported by“Pioneer”and“Leading Goose”R&D Program of Zhejiang(No.2023C03017)National Natural Science Foundation of China(Nos.22225606,22261142663,and 22176029)+1 种基金China Postdoctoral Science Foundation(No.2023M730491)Natural Science Foundation of Huzhou City(No.2022YZ22)。
文摘Diatomic-site catalysts(DASCs)have emerged as a kind of promising heterogeneous candidate catalysts for electrochemical CO_(2)reduction(ECR),which is considered to retain the advantage of single-atom catalysts(SACs)but also introduce opportunities to exceed the limit of single-atom catalysts.In the past few years,tremendous progress has been achieved in this field.Herein,the recent progress in ECR on DASCs has been summarized.It will start with the classification of DASCs.Then the challenges in the precise fabrication and characterization of DASCs have been emphasized.By introducing the advanced ECR performance on DASCs,superior to that on SACs,the synergistic effects of the dual metal atoms are highlighted,as this origin of the advanced ECR performance on DASCs is comprehensively summarized.Finally,the major challenges and perspectives of DASCs have been proposed to shed light on the development of DASCs for ECR application.
基金supported by Open fund of Key Laboratory of Low-grade Energy Utilization Technologies and Systems(Chongqing University)of the Ministry of Education,China(Grant No.LLEUTS-202308)the National Natural Science Foundation of China(Grant No.52106179)+3 种基金the Fundamental Research Program of Shanxi Province,China(Grant No.20210302124017)the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(Grant No.20230012)the Shanxi Scholarship Council of China(Grant No.2023-065)the Graduate Education Practical Innovation of Shanxi Province,China(Grant No.2023SJ056).
文摘In recent years,the dry reforming of methane(DRM)reaction has gained widespread attention due to its effective utilization of two major greenhouse gases.Supported Ni-based catalysts for DRM exhibit a strong dependence on particle size,however,the reaction mechanisms involved remain unclear.In this work,the effect of metal particle size on CO_(2)activation and CO formation was explored in the DRM reaction using the density functional theory.Nix/MgO(x=13,25,37)was constructed to investigate the CO_(2)activation and the formation of CO during the DRM reaction.It is found that CO_(2)is more inclined to undergo chemisorption on Nix/MgO before activation.With the variation in particle size,the main activation pathway of CO_(2)on the catalyst changes.On the smallest Ni13/MgO,CO_(2)tends to directly dissociate,while on the larger Ni25/MgO and Ni37/MgO,the hydrogenation dissociation of CO_(2)is more kinetically favorable.Compared to Ni13/MgO and Ni37/MgO,the oxidation of surface C atoms and the oxidation of CH occur more readily on Ni25/MgO.This indicates that C atoms are less likely to form on Ni25 particle and are more easily to be oxidized.To some extent,the results suggest that Ni25/MgO exhibits superior resistance to carbon formation.
基金supported by the National Natural Science Foundation of China(Nos.22275121,21931005,22105122,52272265)the National Key R&D Program of China(No.2023YFA1506300)+1 种基金the Shanghai Municipal Science and Technology Major Project of China,the Open Foundation Commission of Shaoxing Research Institute of Renewable Energy and Molecular Engineering,China(No.JDSX2022038)the Project of Jiangxi Academy of Sciences,China(No.2023YSTZX01).
文摘Solid oxide electrolysis cells(SOECs)provide a promising way for converting renewable energy into chemical fuels.Traditionally,NiO/CGO(nickel-gadolinium doped ceria)cermet has shown its excellent properties in ionic and electronic conductivity under reducing conditions.Herein,we developed a novel 1D NiO/CGO cathode through a cerium metal-organic framework(MOF)derived process.The cathode’s 1D nanostructure integrated with a microchannel scaffold facilitates enhanced mass transport,providing vertically aligned pathways for CO_(2)and H_(2)O diffusion.Additionally,the 1D framework increases the number of interfacial sites and reduces ion diffusion distances,thereby simplifying electron/ion transport.Consequently,this advanced cathode achieved a significant breakthrough in SOEC performance,maintaining efficient CO_(2)and H_(2)O electrolysis at an extraordinary current density of 1.41 A/cm^(2)at 1.5 V and excellent stability over 24 h at 850℃.The enhanced performance of this newly developed cathode not only achieves a remarkable 100%improvement compared to those of NiO/CGO cathodes with varying geometrical configurations but also surpasses those of commercial NiO/CGO catalysts by an outstanding 40%when tested under identical conditions.The development of the 1D NiO/CGO enhances the efficiency and durability of ceramic cathodes for CO_(2)and H_(2)O co-electrolysis in SOECs and improves the scalability and effectiveness of SOECs in renewable energy applications.
基金supported by the National Natural Science Foundation of China(Grant No.52106179)and the Fundamental Research Program of Shanxi Province,China(Grant No.20210302124017).
文摘The effect of oxygen vacancies on the adsorption and activation of CO_(2) on the surface of different phases of ZrO_(2) is investigated by density functional theory(DFT)calculations.The calculations show that the oxygen vacancies contribute greatly to both the adsorption and activation of CO_(2).The adsorption energy of CO_(2) on the c-ZrO_(2),t-ZrO_(2) and,m-ZrO_(2) surfaces is enhanced to 5,4,and 3 folds with the help of oxygen vacancies,respectively.Moreover,the energy barrier of CO_(2) dissociation on the defective surfaces of c-ZrO_(2),t-ZrO_(2),and m-ZrO_(2) is reduced to 1/2,1/4,and 1/5 of the perfect surface with the assistance of oxygen vacancies.Furthermore,the activation of CO_(2) on the ZrO_(2) surface where oxygen vacancies are present,and changes from an endothermic reaction to an exothermic reaction.This finding demonstrates that the presence of oxygen vacancies promotes the activation of CO_(2) both kinetically and thermodynamically.These results could provide guidance for the high-efficient utilization of CO_(2) at an atomic scale.
基金D.J.thanks the China Scholarship Council(grant no.201906030178)for generous supportWe also acknowledge support by the state of Baden-Württemberg through bwHPC and DFG through grant no.INST 40/467-1 FUGG(JUSTUS cluster).
文摘The capture,storage,and release of CO_(2)is one of the most pressing issues in chemistry.Herein,we designed bis(formazanate)magnesium complexes as precursors,which were synthesized by straightforward transamination between the neutral formazan[PhNNC(4-tBuPh)NNHPh](LH)and[Mg{N(SiMe_(3))_(2)}_(2)].Depending on the solvent,either the homoleptic complex[L_(2)Mg]or the thf-coordinated complex[L_(2)Mg(thf)]was isolated.Reaction of the solvent-free complex[L_(2)Mg]with CO_(2)led to stoichiometric insertion into one of the four Mg–Nbonds with concomitant rearrangement of the ligand scaffold which adopts a trinuclear cagelike structure.The insertion reaction is reversible depending on thermolysis or treatment with tetrahydrofuran,which is corroborated by density functional theory calculations.This showcases the first example of reversible uptake of CO_(2)by an s-block coordination compound.
基金National Key R&D Program of China(2018YFE0115000)the National Natural Science Foundation of China(22003027 and 22174073)+2 种基金the NSF of Tianjin City(19JCYBJC19600)the Frontiers Science Center for New Organic Matter of Nankai University(63181206)supported by the Air Force Office of Scientific Research(AFOSR)under grant number,FA9550-19-1-0077(KHB)。
文摘In this review,the history and outlook of gas-phase CO_(2)activation using single electrons,metal atoms,clusters(mainly metal hydride clusters),and molecules are discussed on both of the experimental and theoretical fronts.Although the development of bulk solid-state materials for the activation and conversion of CO_(2)into value-added products have enjoyed great success in the past several decades,this review focuses only on gas-phase studies,because isolated,well-defined gas-phase systems are ideally suited for high-resolution experiments using state-of-the-art spectrometric and spectroscopic techniques,and for simulations employing modern quantum theoretical methods.The unmatched high complementarity and comparability of experiment and theory in the case of gas-phase investigations bear an enormous potential in providing insights in the reactions of CO_(2)activation at the atomic level.In all of these examples,the reduction and bending of the inert neutral CO_(2)molecule is the critical step determined by the frontier orbitals of reaction participants.Based on the results and outlook summarized in this review,we anticipate that studies of gas-phase CO_(2)activations will be an avenue rich with opportunities for the rational design of novel catalysts based on the knowledge obtained on the atomic level.
基金support from the National Natural Science Foundation of China(No.51706204)National Key Technologies R&D Program(No.YS2018YFE010498)the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 823745.XT and NW thank the financial support from the State Key Laboratory of Electrical Insulation and Power Equipment at Xi’an Jiaotong University(No.EIPE19207).
文摘For the first time,this paper demonstrates a synergistic effect from the combination of a gliding arc discharge plasma with a photocatalyst TiO_(2) for CO_(2) dissociation.The effects of adding a tray downstream the discharge and the combination of the catalyst with plasma have been investigated.Two different combination modes of plasma catalysis,i.e.,in-plasma catalysis and post-plasma catalysis,have been evaluated with the emphasis on the analysis of potential mechanisms.The results show that modifying the gliding arc reactor by the addition of a tray can enhance the fraction of gas treated by plasma,thus improv-ing the reaction performance.An exceptional synergistic effect of combining the gliding arc discharge with TiO_(2) for CO_(2) activation forms in the in-plasma catalysis mode.The presence of TiO_(2) significantly enhances the CO_(2) conversion by 138% and the energy efficiency by 133%at a flow rate of 2 L/min.The plasma activation effect,which produces energetic electrons that can create the electron-hole pairs on the catalyst surface,is believed to be the major contributor to the generation of the plasma catalysis synergy.This mechanism has been further evidenced by the negligible influence of the post-plasma catalysis on the reaction performance.
基金financially supported by the National Key R&D Program of China (2019YFA0210004)the National Natural Science Foundation of China (22125503, 21975242, U2032212)+7 种基金the Strategic Priority Research Program of Chinese Academy of Sciences (XDB36000000)the Youth Innovation Promotion Association of CAS (CX2340007003)the Major Program of Development Foundation of Hefei Center for Physical Science and Technology (2020HSC-CIP003)the Fok Ying-Tong Education Foundation (161012)Users with Excellence Program of Hefei Science Center (2020HSC-UE001)the University Synergy Innovation Program of Anhui Province (GXXT-2020-001)the Anhui Provincial Natural Science Foundation of China (2108085QB69)the Fundamental Research Funds for the Central Universities (WK2060000006)。
文摘Carbon dioxide electroreduction usually suffers from low catalytic activities and debatable reaction mechanisms at present. That may be primarily ascribed to the high energy barrier for carbon dioxide activation over the conventionally fabricated catalysts and the infeasibility of traditional characterization techniques for unveiling the evolution of active sites and reactive intermediates. Two-dimensional(2 D) materials, which possess the active sites with high proportion, high activity and high uniformity, can act as ideal models to manipulate the active sites and understand structure-property relationship. In this review, we overview the boosted carbon dioxide activation by the intrinsic peculiar electronic states of 2D catalysts and the charge localization effect induced by chemical modification of two-dimensional catalysts. We also summarize the recognition of the structural evolutions for active sites in two-dimensional catalysts by means of in situ X-ray diffraction pattern and in situ X-ray absorption spectroscopy. Moreover, we emphasize the detection of the reactive intermediates on active sites in two-dimensional catalysts via in situ Raman spectroscopy and in situ Fourier transform infrared spectroscopy. Finally, we end this review with an outlook on the unresolved issues and future development of carbon dioxide electroreduction.
基金This work was supported by the National Key R&D Program of China(2019YFA0210004,2017YFA0207301,2017YFA0303500)the National Natural Science Foundation of China(21975242,U2032212,21890754,21805267,21703222,11975225)+7 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB36000000)Youth Innovation Promotion Association of CAS(CX2340007003)Key Research Program of Frontier Sciences of CAS(QYZDY-SSW-SLH011)Major Program of Development Foundation of Hefei Center for Physical Science and Technology(2020HSC-CIP003)Users with Excellence Program of Hefei Science Center CAS(2020HSCUE001)The University Synergy Innovation Program of Anhui Province(GXXT-2020-001)the Fok Ying-Tong Education Foundation(161012)Supercomputing USTC and National Supercomputing Center in Shenzhen are acknowledged for computational support.
文摘To realize efficient atmospheric CO_(2) chemisorption and activation,abundant Ti^(3+) sites and oxygen vacancies in TiO_(2) ultrathin layers were designed.Positron annihilation lifetime spectroscopy and theoretical calculations first unveil each oxygen vacancy is associated with the formation of two Ti^(3+)sites,giving a Ti^(3+)-V_(o)-Ti^(3+) configuration.The Ti^(3+)-V_(o)-Ti^(3+) sites could bond with CO_(2) molecules to form a stable configuration,which converted the endoergic chemisorption step to an exoergic process,verified by in-situ Fourier-transform infrared spectra and theoretical calculations.Also,the adjacent Ti^(3+)sites not only favor CO_(2) activation into COOH*via forming a stable Ti^(3+)–C–O–Ti^(3+) configuration,but also facilitate the rate-limiting COOH^(*)scission to CO^(*)by reducing the energy barrier from 0.75 to 0.45 e V.Thus,the Ti^(3+)-V_(o)-TiO_(2) ultrathinlayers could directly capture and photofix atmospheric CO_(2) into near-unity CO,with the corresponding CO_(2)-to-CO conversion ratio of ca.20.2%.
基金This research did not receive any specific grant from funding agencies in the public,commercial,or not-for-profit sectors。
文摘CO_(2)accumulation is inducing an effect of global warming.Adsorption using solid sorbents is proving as an effective strategy for CO_(2)capture and reuse.The aim of this study was to develop amino-functionalized magnetic nanoparticles by depositing various amines through coprecipitation or impregnation-sonication.Structural characteristics were studied through SEM,BET and XRD analyses,evidencing coarse particles with low crystallinity and surface areas of 100–150 m2 g−1,while FT-IR confirmed CO_(2)interacting with substrate.The load of functional group,particles stability,and CO_(2)sorption capacity were assessed through elemental and thermogravimetric analysis.It was found that loads of functional groups ranging from 1.6 to 6.1 wt.%.were deposited,and most samples showed sound stability up to 100°C.Sorption capacities were in the range 0.2–1.5 g gNH2−1,the highest being 1.46 g gNH2−1 forɛ-aminocaproic acid.Such sample also exhibited good recyclability,with a performance drop of 11%after many cycles.CO_(2)uptake decreased with increasing temperature in the range 25–45°C,suggesting a chemical bond between CO_(2)and amines.Amino functionalized particles could thus be an interesting solution for CO_(2)capture and utilization thanks to fast kinetics,recyclability,and ease of separation.
基金supported by the National Key R&D Program of China(2016YFB0100100)the National Natural Science Foundation of China(51702335 and 21773279)+8 种基金Zhejiang Non-profit Technology Applied Research Program(LGG19B010001)Ningbo Municipal Natural Science Foundation(2018A610084)the CAS-EU S&T Cooperation Partner Program(174433KYSB20150013)the Key Laboratory of Bio-based Polymeric Materials of Zhejiang Provincethe funding from Marie Sklodowska-Curie Fellowship in EUthe Engineering and Physical Sciences Research Council(EPSRC),including the SUPERGEN Energy Storage Hub(EP/L019469/1)Enabling Next Generation Lithium Batteries(EP/M009521/1)Henry Royce Institute for Advanced Materials(EP/R00661X/1,EP/S019367/1,EP/R010145/1)the Faraday Institution All-Solid-State Batteries with Li and Na Anodes(FIRG007,FIRG008)for financial support。
文摘Intercalation transition metal oxides (ITMO)have attracted great attention as lithium-ion battery negative electrodes due to high operation safety,high capacity and rapid ion intercalation.However,the intrinsic low electron conductivity plagues the lifetime and cell performance of the ITMO negative electrode.Here we design a new carbon-emcoating architecture through single CO_(2)activation treatment as demonstrated by the Nb_(2)O_(5)/C nanohybrid.Triple structure engineering of the carbon-emcoating Nb_(2)O_(5)/C nanohybrid is achieved in terms of porosity,composition,and crystallographic phase.The carbon-embedding Nb_(2)O_(5)/C nanohybrids show superior cycling and rate performance compared with the conventional carbon coating,with reversible capacity of 387 m A h g(-1)at 0.2 C and 92%of capacity retained after 500cycles at 1 C.Differential electrochemical mass spectrometry(DEMS) indicates that the carbon emcoated Nb_(2)O_(5)nanohybrids present less gas evolution than commercial lithium titanate oxide during cycling.The unique carbon-emcoating technique can be universally applied to other ITMO negative electrodes to achieve high electrochemical performance.
基金supported by the National Natural Science Foundation of China(Grant Nos.51273221&51873066)the Opening Project of Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education and Science and Technology Program of Guangzhou,China(201707010247)
文摘A novel three-dimensional(3D) carbon nanotube foams(CNTF) with ultrahigh specific surface area have been fabricated through a unique but facile one-step synthesis by using CO_2 as both carbon source and activating agent. The activation temperature and time have been adjusted, and the best sample demonstrates a specific surface area of 1959.8 m^2 g^(–1) and a total pore volume of 3.23 cm^3 g^(–1). A reversible capacity of about 870 mAhg^(–1) is maintained at 50 mAg^(–1) when the CNTF used as cathode materials. Meanwhile, the capacity is as large as 320 mAhg^(–1) at the current density of 2 A g^(–1) and the capacity retention is nearly 100% after 500 cycles. These excellent and highly stable battery performances should be attributed to the structural advantages of as-synthesized CNTFs generated by using a facile CO_2-assisted strategy, which may potentially be applied in large scale production of porous 3D carbon materials in the fields of energy storage and conversion.
