The nitrite(NO_(2)^(−))to ammonia(NH3)electroreduction reaction(NO_(2)^(−)RR)would be impeded by sluggish proton-coupled electron transfer kinetics and competitive hydrogen evolution reaction(HER).A key to improving t...The nitrite(NO_(2)^(−))to ammonia(NH3)electroreduction reaction(NO_(2)^(−)RR)would be impeded by sluggish proton-coupled electron transfer kinetics and competitive hydrogen evolution reaction(HER).A key to improving the NH_(3) selectivity is to facilitate adsorption and activation of NO_(2)^(−),which is generally undesirable in unitary species.In this work,an efficient NO_(2)^(−)RR catalyst is constructed by cooperating Pd with In2O3,in which NO_(2)^(−)could adsorb on interfacial dual-site through“Pd–N–O–In”linkage,leading to strengthened NO_(2)^(−)adsorption and easier N=O bond cleavage than that on unitary Pd or In2O3.Moreover,the Pd/In_(2)O_(3)composite exhibits moderate H^(*)adsorption,which may facilitate protonation kinetics while inhibiting competitive HER.As a result,it exhibits a fairly high NH_(3)yield rate of 622.76 mmol h^(−1)g^(−1)cat with a Faradaic efficiency(FE)of 95.72%,good selectivity of 91.96%,and cycling stability towards the NO_(2)^(−)RR,surpassing unitary In_(2)O_(3)and Pd/C electrocatalysts.Besides,computed results indicate that NH_(3)production on Pd/In_(2)O_(3)follows the deoxidation to hydrogenation pathway.This work highlights the significance of H^(*)and NO_(2)^(−)adsorption modulation and N=O activation in NO_(2)^(−)RR electrochemistry by creating synergy between a mediocre catalyst with an appropriate cooperator.展开更多
Polyoxometalates modified with complex cations have attracted increasing attention because of the fascinating properties and the controllable structures.By adjusting the synthesis conditions,four new terpyridine compl...Polyoxometalates modified with complex cations have attracted increasing attention because of the fascinating properties and the controllable structures.By adjusting the synthesis conditions,four new terpyridine complexes based hybrid POMs,[(TPY-H)CuCl]_(4)[W_(10)O_(32)]·2DMF·2H_(2)O(1),[(TPY-H)Cu(DMSO)(H_(2)O)]_(2)[W_(10)O_(32)]·2H_(2)O(2),[(TPY-H)_(2)Cu]_(2)[W_(10)O_(32)]·6DMSO·8H_(2)O(3) and[(TPY-Br)CuCl(DMSO)(H_(2)O)]_(2)[(TPY-Br)CuCl]_(2)[W_(10)O_(32)]·2DMSO·4H_(2)O(4),were prepared by using‘one-pot’method.Sing-crystal X-ray diffraction analyses,infrared radiation,etc.,revealed the structural composition of compounds 1—4,which indicates that synthesis conditions have a directional regulatory effect on the compounds synthesis.Thioether oxidation catalytic reactions show 1—4 have good catalytic activities,and powder X-ray diffraction and thermogravimetry analysis show 1—4 have superduper catalytic stability.Moreover,4 has better catalytic activity because of the different structure of terpyridine complexes.Therefore,a possible mechanism of dual-site catalysis by both cations and anions is proposed.展开更多
Traditional garnet solid electrolyte(Li_(7)La_(3)Zr_(2)O_(12))suffers from low room temperature ionic conductivity,poor air stability,high sintering temperature and energy consumption.Considering the development prosp...Traditional garnet solid electrolyte(Li_(7)La_(3)Zr_(2)O_(12))suffers from low room temperature ionic conductivity,poor air stability,high sintering temperature and energy consumption.Considering the development prospects of high-entropy materials with high structural disorder and strong component controllability in the field of electrochemical energy storage,herein,a novel high-entropy garnet-type oxide solid electrolyte,Li_(5.75)Ga_(0.25)La_(3)Zr_(0.5)Ti_(0.5)Sn_(0.5)Nb_(0.5)O_(12)(LGLZTSNO)was constructed by partially replacing the Li and Zr sites in Li_(7)La_(3)Zr_(2)O_(12)with Ga and Ti/Sn/Nb elements,respectively.The experimental and density functional theory(DFT)calculation results show that the high-entropy LGLZTSNO electrolyte has preferable room temperature ion conductivity,air stability,interface contact performance with lithium anode,and the ability to suppress lithium dendrites.Thanks to the improvement of electrolyte performance,the critical current density of Li/Ag@LGLZTSNO/Li symmetric cell was increased from 0.42 to 1.57 mA cm^(−2),and the interface area specific impedance(IASR)was reduced from 765.2 to 42.3Ωcm^(2).Meanwhile,the Li/Ag@LGLZTSNO/LFP full cell also exhibits excellent rate performance and cycling performance(148 mA h g^(−1)at 0.1 C and 124 mA h g^(−1)at 0.5 C,capacity retention up to 84.8%after 100 cycles at 0.1 C),showing the application prospects of high-entropy LGLZTSNO solid electrolyte in high-performance all solid state lithium batteries.展开更多
One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing se...One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing serious issues in overall efficiency.New promotional effects are highly desired for boosting the activity and regulating the selectivity of conventional tandem catalysts.In this work,we report a high-performance tandem catalyst with maximized synergistic effect among each counterpart by preciously manipulating the spatial structure,which involves the active CeO_(2)/Pt component as kernel,the densely-coated N-doped C(NC)layer as selectivity controller,and the differentially-grown Co species as catalytic performance regulators.Through comprehensive investigations,the unique growth mechanism and the promotion effect of Co regulators are clarified.Specifically,the surface-landed Co clusters(Cocs)are crucial to selectivity by altering the adsorption configuration of benzylideneaniline intermediates.Meanwhile,the inner Co particles(Cops)are essential for activity by denoting their electrons to neighboring Ptps.Benefiting from the unique promotion effect,a remarkably-improved catalytic efficiency(100%nitrobenzene conversion with 94%N-benzylaniline selectivity)is achieved at a relatively low temperature of 80℃,which is much better than that of CeO_(2)/Pt(100%nitrobenzene conversion with 12%N-benzylaniline selectivity)and CeO_(2)/Pt/NC(35%nitrobenzene conversion with 94%benzylideneaniline selectivity).展开更多
A dual-site fluorescent probe with double bond and aldehyde as reactive sites, was designed for the selective detection of sulfite and biothiols. Sulfite reacts with conjugate bond selectively, while Cys responses wit...A dual-site fluorescent probe with double bond and aldehyde as reactive sites, was designed for the selective detection of sulfite and biothiols. Sulfite reacts with conjugate bond selectively, while Cys responses with aldehyde and GSH occurs substitution reaction. Different interactions cause different absorption and fluorescence responses. Moreover, it could be further applied in imaging in living cells.展开更多
Electrocatalytic reduction of nitrogen into ammonia(NH_(3))is a highly attractive but challenging route for NH_(3)production.We propose to realize a synergetic work of multi reaction sites to overcome the limitation o...Electrocatalytic reduction of nitrogen into ammonia(NH_(3))is a highly attractive but challenging route for NH_(3)production.We propose to realize a synergetic work of multi reaction sites to overcome the limitation of sustainable NH_(3)production.Herein,using ruthenium-sulfur-carbon(Ru-S-C)catalyst as a prototype,we show that the Ru/S dual-site cooperates to catalyse eletrocatalytic nitrogen reduction reaction(eNRR)at ambient conditions.With the combination of theoretical calculations,in situ Raman spectroscopy,and experimental observation,we demonstrate that such Ru/S dual-site cooperation greatly facilitates the activation and first protonation of N_(2)in the rate-determining step of eNRR.As a result,Ru-S-C catalyst exhibits significantly enhanced eNRR performance compared with the routine Ru-N-C catalyst via a single-site catalytic mechanism.We anticipate that our specifically designed dual-site collaborative catalytic mechanism will open up a new way to offers new opportunities for advancing sustainable NH_(3)production.展开更多
G-quadruplexes （G4s） play important roles in biological systems, such as telomere maintenance, replication, and transcription. Based on the DNA sequence, loop geometry, and the local environments, G4s can be classif...G-quadruplexes （G4s） play important roles in biological systems, such as telomere maintenance, replication, and transcription. Based on the DNA sequence, loop geometry, and the local environments, G4s can be classified into different conformations. It is important to detect different types of G4s to monitor the diseases related with G4s. Most ligands bind to G4s based on end-stacking modes, while rare ligands bind to G4s through groove binding modes. We have found that a cyanine dye DMSB interacts with parallel G4 by end-stacking and groove simultaneous binding mode. In this article, we found that DMSB could simply discriminate parallel G4s from other DNA motifs by using UV-vis spectrum. These results give some clues to develop high specificity G4 probes.展开更多
Affected by cobalt(Co)supply bottlenecks and high costs,Co-free Ni-rich layered cathodes are considered the most promising option for economical and sustainable development of lithium-ion batteries(LIBs).Low-cost LiNi...Affected by cobalt(Co)supply bottlenecks and high costs,Co-free Ni-rich layered cathodes are considered the most promising option for economical and sustainable development of lithium-ion batteries(LIBs).Low-cost LiNi_(x)Al_(1-x)O_(2)(x≥0.9)cathode are rarely reported due to their chemo-mechanical instabilities and poor cycle life.Herein,we employ a strategy of Mg/W Li/Ni dualsite co-doping LiNi_(0.9)Al_(0.1)O_(2)(named as LNA90)cathodes to enhance cycling stability by modifying the crystal structure and forming a center radially aligned microstructure.The Mg/W co-doped LiNi_(0.9)Al_(0.1)O_(2)cathode(named as LNAMW)exhibits high capacity retention of 94.9%at 1 C and 3.0-4.5 V after 100 cycles with 22.0%increase over the pristine cathode LNA90 and maintains the intact particle morphology.Meanwhile,the cycling performance of LNAMW cathode exceeds that of most reported Ni-rich cathodes(Ni mol%>80%).Our work offers a straightforward,efficient,and scalable strategy for the future design of Cofree Ni-rich cathodes to facilitate the development of economical lithium-ion batteries.展开更多
Electrochemical nitrogen reduction reaction(NRR)paves a new way to cost-efficient production of ammonia,but is still challenging in the sluggish kinetics caused by hydrogen evolution reaction competition and chemical ...Electrochemical nitrogen reduction reaction(NRR)paves a new way to cost-efficient production of ammonia,but is still challenging in the sluggish kinetics caused by hydrogen evolution reaction competition and chemical inertness of N≡N bond.Herein,we report a“dual-site”strategy for boosting NRR performance.A high-performance catalyst is successfully constructed by anchoring isolated Fe and Mo atoms on hierarchical N doped carbon nanotubes through a facile self-sacrificing template route,which exhibits a remarkably improved NH3 yield rate of 26.8μg·h^(−1)·mg with 11.8%Faradaic efficiency,which is 2.5 and 1.6 times larger than those of Fe/NC and Mo/NC.The enhancement can be attributed to the unique hierarchical structure that profits from the contact of electrode and electrolyte,thus improving the mass and electron transport.More importantly,the in situ Fourier transform infrared spectroscopy(in situ FTIR)result firmly demonstrates the crucial role of the coupling of Fe and Mo atoms,which can efficiently boost the generation and transmission of*N2Hy intermediates,leading to an accelerated reaction rate.展开更多
HSP90(heat shock protein 90)是一种重要的分子伴侣蛋白,负责客户蛋白的激活和成熟。靶向HSP90可通过竞争性占据ATP位点或者干扰HSP90与共伴侣蛋白之间的蛋白互作位点,进而有效抑制癌细胞增殖。因此,HSP90的位点识别与功能的研究对于...HSP90(heat shock protein 90)是一种重要的分子伴侣蛋白,负责客户蛋白的激活和成熟。靶向HSP90可通过竞争性占据ATP位点或者干扰HSP90与共伴侣蛋白之间的蛋白互作位点,进而有效抑制癌细胞增殖。因此,HSP90的位点识别与功能的研究对于分子发现至关重要。本研究聚焦于多肽P1,揭示了其与HSP90之间的双重结合机制,P1能够同时作用于HSP90的ATP结合位点和共伴侣蛋白CDC37(cell division cycle 37)结合界面。通过ATPase实验和Co-IP实验,发现P1具有同时抑制ATP的活性和HSP90-CDC37之间的蛋白互作的能力,这为靶向HSP90伴侣系统的新型抑制剂提供了新思路。展开更多
Comprehending the mechanism of methane adsorption in shales is a crucial step towards optimizing the development of deep-buried shale gas. This is because the methane adsorbed in shale represents a significant proport...Comprehending the mechanism of methane adsorption in shales is a crucial step towards optimizing the development of deep-buried shale gas. This is because the methane adsorbed in shale represents a significant proportion of the subsurface shale gas resource. To properly characterize the methane adsorption on shale, which exhibits diverse mineral compositions and multi-scale pore sizes, it is crucial to capture the energy heterogeneity of the adsorption sites. In this paper, a dual-site Langmuir model is proposed, which accounts for the temperature and pressure dependence of the density of the adsorbed phase. The model is applied to the isothermals of methane adsorption on shale, at pressures of up to 30 MPa and temperatures ranging from 40 to 100 ℃. The results show that the proposed model can describe the adsorption behavior of methane on shale more accurately than conventional models, which assume a constant value for the density of adsorbed phase. Furthermore, the proposed model can be extrapolated to higher temperatures and pressures. Thermodynamic parameters were analyzed using correctly derived equations. The results indicate that the widely used, but incorrect, equation would underestimate the isosteric heat of adsorption. Neglecting the real gas behavior, volume of the adsorbed phase, and energy heterogeneity of the adsorption sites can lead to overestimation of the isosteric heat of adsorption. Furthermore, the isosteric heat evaluated from excess adsorption data can only be used to make a rough estimate of the real isosteric heat at very low pressure.展开更多
基金supported by the National Key R&D Program of China(Nos.2022YFA1503104 and 2022YFA1503102)the Natural Science Foundation of Shandong Province(No.2022HWYQ-009)+2 种基金the Natural Science Foundation of Jiangsu Province(No.BK20230243)Taishan Scholars Project(No.tspd20230601)Qilu Young Scholars Program of Shandong University.
文摘The nitrite(NO_(2)^(−))to ammonia(NH3)electroreduction reaction(NO_(2)^(−)RR)would be impeded by sluggish proton-coupled electron transfer kinetics and competitive hydrogen evolution reaction(HER).A key to improving the NH_(3) selectivity is to facilitate adsorption and activation of NO_(2)^(−),which is generally undesirable in unitary species.In this work,an efficient NO_(2)^(−)RR catalyst is constructed by cooperating Pd with In2O3,in which NO_(2)^(−)could adsorb on interfacial dual-site through“Pd–N–O–In”linkage,leading to strengthened NO_(2)^(−)adsorption and easier N=O bond cleavage than that on unitary Pd or In2O3.Moreover,the Pd/In_(2)O_(3)composite exhibits moderate H^(*)adsorption,which may facilitate protonation kinetics while inhibiting competitive HER.As a result,it exhibits a fairly high NH_(3)yield rate of 622.76 mmol h^(−1)g^(−1)cat with a Faradaic efficiency(FE)of 95.72%,good selectivity of 91.96%,and cycling stability towards the NO_(2)^(−)RR,surpassing unitary In_(2)O_(3)and Pd/C electrocatalysts.Besides,computed results indicate that NH_(3)production on Pd/In_(2)O_(3)follows the deoxidation to hydrogenation pathway.This work highlights the significance of H^(*)and NO_(2)^(−)adsorption modulation and N=O activation in NO_(2)^(−)RR electrochemistry by creating synergy between a mediocre catalyst with an appropriate cooperator.
基金the support from the Project Foundation of Hunan Provincial Education Department(21C1642,22B0641,21B0584)the Research project of Changsha Normal University(XJYB202103)+1 种基金the Natural Science Foundation of Hunan Province(2023JJ40235)the National Natural Science Foundation of China(22204050).
文摘Polyoxometalates modified with complex cations have attracted increasing attention because of the fascinating properties and the controllable structures.By adjusting the synthesis conditions,four new terpyridine complexes based hybrid POMs,[(TPY-H)CuCl]_(4)[W_(10)O_(32)]·2DMF·2H_(2)O(1),[(TPY-H)Cu(DMSO)(H_(2)O)]_(2)[W_(10)O_(32)]·2H_(2)O(2),[(TPY-H)_(2)Cu]_(2)[W_(10)O_(32)]·6DMSO·8H_(2)O(3) and[(TPY-Br)CuCl(DMSO)(H_(2)O)]_(2)[(TPY-Br)CuCl]_(2)[W_(10)O_(32)]·2DMSO·4H_(2)O(4),were prepared by using‘one-pot’method.Sing-crystal X-ray diffraction analyses,infrared radiation,etc.,revealed the structural composition of compounds 1—4,which indicates that synthesis conditions have a directional regulatory effect on the compounds synthesis.Thioether oxidation catalytic reactions show 1—4 have good catalytic activities,and powder X-ray diffraction and thermogravimetry analysis show 1—4 have superduper catalytic stability.Moreover,4 has better catalytic activity because of the different structure of terpyridine complexes.Therefore,a possible mechanism of dual-site catalysis by both cations and anions is proposed.
基金supported by the Natural Science Foundation of China(61901142)the Key Research and Development Project of Hainan Province(ZDYF2022SHFZ093).
文摘Traditional garnet solid electrolyte(Li_(7)La_(3)Zr_(2)O_(12))suffers from low room temperature ionic conductivity,poor air stability,high sintering temperature and energy consumption.Considering the development prospects of high-entropy materials with high structural disorder and strong component controllability in the field of electrochemical energy storage,herein,a novel high-entropy garnet-type oxide solid electrolyte,Li_(5.75)Ga_(0.25)La_(3)Zr_(0.5)Ti_(0.5)Sn_(0.5)Nb_(0.5)O_(12)(LGLZTSNO)was constructed by partially replacing the Li and Zr sites in Li_(7)La_(3)Zr_(2)O_(12)with Ga and Ti/Sn/Nb elements,respectively.The experimental and density functional theory(DFT)calculation results show that the high-entropy LGLZTSNO electrolyte has preferable room temperature ion conductivity,air stability,interface contact performance with lithium anode,and the ability to suppress lithium dendrites.Thanks to the improvement of electrolyte performance,the critical current density of Li/Ag@LGLZTSNO/Li symmetric cell was increased from 0.42 to 1.57 mA cm^(−2),and the interface area specific impedance(IASR)was reduced from 765.2 to 42.3Ωcm^(2).Meanwhile,the Li/Ag@LGLZTSNO/LFP full cell also exhibits excellent rate performance and cycling performance(148 mA h g^(−1)at 0.1 C and 124 mA h g^(−1)at 0.5 C,capacity retention up to 84.8%after 100 cycles at 0.1 C),showing the application prospects of high-entropy LGLZTSNO solid electrolyte in high-performance all solid state lithium batteries.
基金supported by financial aid from the National Science and Technology Major Project of China(No.2021YFB3500700)the National Natural Science Foundation of China(Nos.22020102003,22025506,and 22271274)the Program of Science and Technology Development Plan of Jilin Province of China(Nos.20230101035JC and 20230101022JC).
文摘One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing serious issues in overall efficiency.New promotional effects are highly desired for boosting the activity and regulating the selectivity of conventional tandem catalysts.In this work,we report a high-performance tandem catalyst with maximized synergistic effect among each counterpart by preciously manipulating the spatial structure,which involves the active CeO_(2)/Pt component as kernel,the densely-coated N-doped C(NC)layer as selectivity controller,and the differentially-grown Co species as catalytic performance regulators.Through comprehensive investigations,the unique growth mechanism and the promotion effect of Co regulators are clarified.Specifically,the surface-landed Co clusters(Cocs)are crucial to selectivity by altering the adsorption configuration of benzylideneaniline intermediates.Meanwhile,the inner Co particles(Cops)are essential for activity by denoting their electrons to neighboring Ptps.Benefiting from the unique promotion effect,a remarkably-improved catalytic efficiency(100%nitrobenzene conversion with 94%N-benzylaniline selectivity)is achieved at a relatively low temperature of 80℃,which is much better than that of CeO_(2)/Pt(100%nitrobenzene conversion with 12%N-benzylaniline selectivity)and CeO_(2)/Pt/NC(35%nitrobenzene conversion with 94%benzylideneaniline selectivity).
基金financially supported by the National Natural Science Foundation of China (Nos.21572147, 21232005 and J1103315)
文摘A dual-site fluorescent probe with double bond and aldehyde as reactive sites, was designed for the selective detection of sulfite and biothiols. Sulfite reacts with conjugate bond selectively, while Cys responses with aldehyde and GSH occurs substitution reaction. Different interactions cause different absorption and fluorescence responses. Moreover, it could be further applied in imaging in living cells.
文摘Electrocatalytic reduction of nitrogen into ammonia(NH_(3))is a highly attractive but challenging route for NH_(3)production.We propose to realize a synergetic work of multi reaction sites to overcome the limitation of sustainable NH_(3)production.Herein,using ruthenium-sulfur-carbon(Ru-S-C)catalyst as a prototype,we show that the Ru/S dual-site cooperates to catalyse eletrocatalytic nitrogen reduction reaction(eNRR)at ambient conditions.With the combination of theoretical calculations,in situ Raman spectroscopy,and experimental observation,we demonstrate that such Ru/S dual-site cooperation greatly facilitates the activation and first protonation of N_(2)in the rate-determining step of eNRR.As a result,Ru-S-C catalyst exhibits significantly enhanced eNRR performance compared with the routine Ru-N-C catalyst via a single-site catalytic mechanism.We anticipate that our specifically designed dual-site collaborative catalytic mechanism will open up a new way to offers new opportunities for advancing sustainable NH_(3)production.
基金supported by Major National Basic Research Projects (973,No.2013CB733701)National Natural Science Foundation of China (Nos.81072576,91027033,21302188,21205121,21305145 and 31200576)Chinese Academy of Sciences (No.KJCX2-EW-N06-01)
文摘G-quadruplexes （G4s） play important roles in biological systems, such as telomere maintenance, replication, and transcription. Based on the DNA sequence, loop geometry, and the local environments, G4s can be classified into different conformations. It is important to detect different types of G4s to monitor the diseases related with G4s. Most ligands bind to G4s based on end-stacking modes, while rare ligands bind to G4s through groove binding modes. We have found that a cyanine dye DMSB interacts with parallel G4 by end-stacking and groove simultaneous binding mode. In this article, we found that DMSB could simply discriminate parallel G4s from other DNA motifs by using UV-vis spectrum. These results give some clues to develop high specificity G4 probes.
基金The National Natural Science Foundation of China(No.52004116)the Major Science and Technology Special Program of Yunnan Province(No.202202AG050003)+2 种基金the Applied Basic Research Plan of Yunnan Province(Nos.202101AS070020,202201AT070184,202101BE070001-016,and 202001AU070039)the High-level Talent Introduction Scientific Research Start Project of KUST(No.20190015)the analysis and testing fund of Kunming University of Technology(No.2021M20202202144)are gratefully acknowledged.
文摘Affected by cobalt(Co)supply bottlenecks and high costs,Co-free Ni-rich layered cathodes are considered the most promising option for economical and sustainable development of lithium-ion batteries(LIBs).Low-cost LiNi_(x)Al_(1-x)O_(2)(x≥0.9)cathode are rarely reported due to their chemo-mechanical instabilities and poor cycle life.Herein,we employ a strategy of Mg/W Li/Ni dualsite co-doping LiNi_(0.9)Al_(0.1)O_(2)(named as LNA90)cathodes to enhance cycling stability by modifying the crystal structure and forming a center radially aligned microstructure.The Mg/W co-doped LiNi_(0.9)Al_(0.1)O_(2)cathode(named as LNAMW)exhibits high capacity retention of 94.9%at 1 C and 3.0-4.5 V after 100 cycles with 22.0%increase over the pristine cathode LNA90 and maintains the intact particle morphology.Meanwhile,the cycling performance of LNAMW cathode exceeds that of most reported Ni-rich cathodes(Ni mol%>80%).Our work offers a straightforward,efficient,and scalable strategy for the future design of Cofree Ni-rich cathodes to facilitate the development of economical lithium-ion batteries.
基金supported by the financial aid from National Science and Technology Major Project of China(No.2021YFB3500700)National Natural Science Foundation of China(Nos.22020102003,22025506,and 22271274)+2 种基金Key Research Program of the Chinese Academy of Sciences(No.ZDRW-CN-2021-3-3)K.C.Wong Education Foundation(No.GJTD-2018-09)Innovation and Entrepreneurship Program of Jilin Province(No.E2390202).
文摘Electrochemical nitrogen reduction reaction(NRR)paves a new way to cost-efficient production of ammonia,but is still challenging in the sluggish kinetics caused by hydrogen evolution reaction competition and chemical inertness of N≡N bond.Herein,we report a“dual-site”strategy for boosting NRR performance.A high-performance catalyst is successfully constructed by anchoring isolated Fe and Mo atoms on hierarchical N doped carbon nanotubes through a facile self-sacrificing template route,which exhibits a remarkably improved NH3 yield rate of 26.8μg·h^(−1)·mg with 11.8%Faradaic efficiency,which is 2.5 and 1.6 times larger than those of Fe/NC and Mo/NC.The enhancement can be attributed to the unique hierarchical structure that profits from the contact of electrode and electrolyte,thus improving the mass and electron transport.More importantly,the in situ Fourier transform infrared spectroscopy(in situ FTIR)result firmly demonstrates the crucial role of the coupling of Fe and Mo atoms,which can efficiently boost the generation and transmission of*N2Hy intermediates,leading to an accelerated reaction rate.
基金The first author thanks Dr.Nicholas P.Stadie at the Montana State University,USA,for helpful discussions.Dr.Qian Zhang would like to thank Postdoctoral Research Foundation of China(2021TQ0003)for supporting his research.
文摘Comprehending the mechanism of methane adsorption in shales is a crucial step towards optimizing the development of deep-buried shale gas. This is because the methane adsorbed in shale represents a significant proportion of the subsurface shale gas resource. To properly characterize the methane adsorption on shale, which exhibits diverse mineral compositions and multi-scale pore sizes, it is crucial to capture the energy heterogeneity of the adsorption sites. In this paper, a dual-site Langmuir model is proposed, which accounts for the temperature and pressure dependence of the density of the adsorbed phase. The model is applied to the isothermals of methane adsorption on shale, at pressures of up to 30 MPa and temperatures ranging from 40 to 100 ℃. The results show that the proposed model can describe the adsorption behavior of methane on shale more accurately than conventional models, which assume a constant value for the density of adsorbed phase. Furthermore, the proposed model can be extrapolated to higher temperatures and pressures. Thermodynamic parameters were analyzed using correctly derived equations. The results indicate that the widely used, but incorrect, equation would underestimate the isosteric heat of adsorption. Neglecting the real gas behavior, volume of the adsorbed phase, and energy heterogeneity of the adsorption sites can lead to overestimation of the isosteric heat of adsorption. Furthermore, the isosteric heat evaluated from excess adsorption data can only be used to make a rough estimate of the real isosteric heat at very low pressure.
