Electrocatalytic N_(2)reduction reaction (NRR) has been considered as a promising and alternative strategy for the synthesis of NH_(3),which will contribute to the goal of carbon neutrality and sustainability.However,...Electrocatalytic N_(2)reduction reaction (NRR) has been considered as a promising and alternative strategy for the synthesis of NH_(3),which will contribute to the goal of carbon neutrality and sustainability.However,this process often suffers from the barrier for N_(2)activation and competitive reactions,resulting in poor NH_(3)yield and low Faraday efficiency (FE).Here,we report a two-dimensiona(2D) ultrathin FeS nanosheets with high conductivity through a facile and scalable method under mild condition.The synthesized FeS catalysts can be used as the work electrode in the electrochemical NRR cell with N_(2)-saturated Na_(2)SO_(4)electrolyte.Such a catalyst shows a NH_(3)yield of 9.0μg·h^(-1)·mg^(-1)(corresponding to 1.47×10^(-4)μmol·s^(-1)·cm^(-2)) and a high FE of 12.4%,which significantly outperformed the other most NRR catalysts.The high catalytic performance of FeS can be attributed to the 2D mackinawite structure,which provides a new insight to explore low-cost and high-performance Fe-based electrocatalysts,as well as accelerates the practical application of the NRR.展开更多
Palladium(Pd) nanostructures are highly promising electrocatalysts for the carbon dioxide electrochemical reduction(CO_(2) ER). At present, it is still challenge for the synthesis of Pd nanostructures with high activi...Palladium(Pd) nanostructures are highly promising electrocatalysts for the carbon dioxide electrochemical reduction(CO_(2) ER). At present, it is still challenge for the synthesis of Pd nanostructures with high activity, selectivity and stability. In this work, a facile PdII-complex pyrolysis method is applied to synthesize the high-quality one-dimensional heterostructured Pd/Pd O nanowires(Pd/Pd O H-NWs).The as-prepared Pd/Pd O H-NWs have a large electrochemically active surface area, abundant defects and Pd/Pd O heterostructure. Electrochemical measurement results reveal that Pd/Pd O H-NWs exhibit up to 94% CO Faraday efficiency with a current density of 11.6 m A cm^(-2) at an applied potential of -0.8 V. Meanwhile, Pd/Pd O H-NWs can achieve a stable catalytic process of 12 h for CO_(2) ER. Such outstanding CO_(2) ER performance of Pd/Pd O H-NWs has also been verified in the flow cell test. The density functional theory calculations indicate that Pd/Pd O heterostructure can significantly weaken the CO adsorption on Pd sites, which improves the CO tolerance and consequently enhances the catalytic performance of Pd/Pd O H-NWs for CO_(2) ER. This work highlights a facile complex pyrolysis strategy for the synthesis of Pd-based CO_(2) ER catalysts and provides a new application instance of metal/metal oxide heterostructure in electrocatalysis.展开更多
Due to their environmentally friendly nature and high energy density,direct ethanol fuel cells have attracted extensive research attention in recent decades.However,the actual Faraday efficiency of the ethanol oxidati...Due to their environmentally friendly nature and high energy density,direct ethanol fuel cells have attracted extensive research attention in recent decades.However,the actual Faraday efficiency of the ethanol oxidation reaction(EOR)is much lower than its theoretical value and the reaction kinetics of the EOR is sluggish due to insufficient active sites on the electrocatalyst surface.Pt/C is recognized as one of the most promising electrocatalysts for the EOR.Thus,the microscopic interfacial reaction mechanisms of the EOR on Pt/C were systematically studied in this work.In metal hydroxide solutions,hydrated alkali cations were found to bind with OH_(ad)through noncovalent interactions to form clusters and occupy the active sites on the Pt/C electrocatalyst surface,thus resulting in low Faraday efficiency and sluggish kinetics of the EOR.To reduce the negative effect of the noncovalent interactions on the EOR,a shield was made on the electrocatalyst surface using 4-trifluoromethylphenyl,resulting in twice the EOR catalytic reactivity of Pt/C.展开更多
Electrocatalytic reduction of ethylenediamine tetraacetic acid copper(CuEDTA),a typical refractory heavy metal complexation pollutant,is an environmental benign method that operates at mild condition.Unfortunately,the...Electrocatalytic reduction of ethylenediamine tetraacetic acid copper(CuEDTA),a typical refractory heavy metal complexation pollutant,is an environmental benign method that operates at mild condition.Unfortunately,the selective reduction of CuEDTA is still a big challenge in cathodic process.In this work,we report a MoS_(2) nanosheet/graphite felt(GF)cathode,which achieves an average Faraday efficiency of 29.6%and specific removal rate(SRR)of 0.042 mol/cm^(2)/h for CuEDTA at−0.65 V vs SCE(saturated calomel electrode),both of which are much higher than those of the commonly reported electrooxidation technology-based removal systems.Moreover,a proofof-concept CuEDTA/Zn battery with Zn anode and MoS_(2)/GF cathode is demonstrated,which has bifunctions of simultaneous CuEDTA removal and energy output.This is one of the pioneer studies on the electrocatalytic reduction of heavy metal complex and CuEDTA/Zn battery,which brings new insights in developing efficient electrocatalytic reduction system for pollution control and energy output.展开更多
Electrochemical CO_(2) reduction reaction(CO_(2)RR)offers a promising strategy for CO_(2) conversion into value-added C2+products and facilitates the storage of renewable resources under comparatively mild conditions,...Electrochemical CO_(2) reduction reaction(CO_(2)RR)offers a promising strategy for CO_(2) conversion into value-added C2+products and facilitates the storage of renewable resources under comparatively mild conditions,but still remains a challenge.Herein,we propose the strategy of surface reconstruction and interface integration engineering to construct tuneable Cu^(0)-Cu^(+)-Cu^(2+)sites and oxygen vacancy oxide derived from CeO_(2)/CuO nanosheets(OD-CeO_(2)/CuO NSs)heterojunction catalysts and promote the activity and selectivity of CO_(2)RR.The optimized OD-CeO_(2)/CuO electrocatalyst shows the maximum Faradic efficiencies for C2+products in the H-type cell,which reaches 69.8%at−1.25 V versus a reversible hydrogen electrode(RHE).Advanced characterization analysis and density functional theory(DFT)calculations further confirm the fact that the existence of oxygen vacancies and Cu^(0)-Cu^(+)-Cu^(2+)sites modified with CeO_(2) is conducive to CO_(2) adsorption and activation,enhances the hydrogenation of^(*)CO to^(*)CHO,and further promotes the dimerization of^(*)CHO,thus promoting the selectivity of C2+generation.This facile interface integration and surface reconstruction strategy provides an ideal strategy to guide the design of CO_(2)RR electrocatalysts.展开更多
基金financially supported by the Fundamental Research Program of Shanxi Province, China (Nos. 202303021222190, 202203021212243, and 2023L160)the National Natural Science Foundation of China (No. 22202151 and 22209033)the Fundamental Research Program of Shanxi Normal University, China (No. J CYJ2023015)。
文摘Electrocatalytic N_(2)reduction reaction (NRR) has been considered as a promising and alternative strategy for the synthesis of NH_(3),which will contribute to the goal of carbon neutrality and sustainability.However,this process often suffers from the barrier for N_(2)activation and competitive reactions,resulting in poor NH_(3)yield and low Faraday efficiency (FE).Here,we report a two-dimensiona(2D) ultrathin FeS nanosheets with high conductivity through a facile and scalable method under mild condition.The synthesized FeS catalysts can be used as the work electrode in the electrochemical NRR cell with N_(2)-saturated Na_(2)SO_(4)electrolyte.Such a catalyst shows a NH_(3)yield of 9.0μg·h^(-1)·mg^(-1)(corresponding to 1.47×10^(-4)μmol·s^(-1)·cm^(-2)) and a high FE of 12.4%,which significantly outperformed the other most NRR catalysts.The high catalytic performance of FeS can be attributed to the 2D mackinawite structure,which provides a new insight to explore low-cost and high-performance Fe-based electrocatalysts,as well as accelerates the practical application of the NRR.
基金supported by the National Natural Science Foundation of China(51873100)Natural Science Foundation of Shaanxi Province(2020JZ-23)+2 种基金the Fundamental Research Funds for the Central Universities(GK202101005 and 2021CBLZ004)the Innovation Team Project for Graduate Student at Shaanxi Normal University(TD2020048Y)the 111 Project(B14041)。
文摘Palladium(Pd) nanostructures are highly promising electrocatalysts for the carbon dioxide electrochemical reduction(CO_(2) ER). At present, it is still challenge for the synthesis of Pd nanostructures with high activity, selectivity and stability. In this work, a facile PdII-complex pyrolysis method is applied to synthesize the high-quality one-dimensional heterostructured Pd/Pd O nanowires(Pd/Pd O H-NWs).The as-prepared Pd/Pd O H-NWs have a large electrochemically active surface area, abundant defects and Pd/Pd O heterostructure. Electrochemical measurement results reveal that Pd/Pd O H-NWs exhibit up to 94% CO Faraday efficiency with a current density of 11.6 m A cm^(-2) at an applied potential of -0.8 V. Meanwhile, Pd/Pd O H-NWs can achieve a stable catalytic process of 12 h for CO_(2) ER. Such outstanding CO_(2) ER performance of Pd/Pd O H-NWs has also been verified in the flow cell test. The density functional theory calculations indicate that Pd/Pd O heterostructure can significantly weaken the CO adsorption on Pd sites, which improves the CO tolerance and consequently enhances the catalytic performance of Pd/Pd O H-NWs for CO_(2) ER. This work highlights a facile complex pyrolysis strategy for the synthesis of Pd-based CO_(2) ER catalysts and provides a new application instance of metal/metal oxide heterostructure in electrocatalysis.
基金National Key R&D Program of China under Grant,Grant/Award Number:2021YFC1910601National Natural Science Foundation of China,Grant/Award Number:52104402HBIS Group Co.,Ltd Key R&D Program under Grant,Grant/Award Numbers:20210032,HG2022111。
文摘Due to their environmentally friendly nature and high energy density,direct ethanol fuel cells have attracted extensive research attention in recent decades.However,the actual Faraday efficiency of the ethanol oxidation reaction(EOR)is much lower than its theoretical value and the reaction kinetics of the EOR is sluggish due to insufficient active sites on the electrocatalyst surface.Pt/C is recognized as one of the most promising electrocatalysts for the EOR.Thus,the microscopic interfacial reaction mechanisms of the EOR on Pt/C were systematically studied in this work.In metal hydroxide solutions,hydrated alkali cations were found to bind with OH_(ad)through noncovalent interactions to form clusters and occupy the active sites on the Pt/C electrocatalyst surface,thus resulting in low Faraday efficiency and sluggish kinetics of the EOR.To reduce the negative effect of the noncovalent interactions on the EOR,a shield was made on the electrocatalyst surface using 4-trifluoromethylphenyl,resulting in twice the EOR catalytic reactivity of Pt/C.
基金supported by the National Key R&D Program of China(2019YFC1905400)the Fundamental Research Funds for the Central Universities(2022-4-ZD-08).
文摘Electrocatalytic reduction of ethylenediamine tetraacetic acid copper(CuEDTA),a typical refractory heavy metal complexation pollutant,is an environmental benign method that operates at mild condition.Unfortunately,the selective reduction of CuEDTA is still a big challenge in cathodic process.In this work,we report a MoS_(2) nanosheet/graphite felt(GF)cathode,which achieves an average Faraday efficiency of 29.6%and specific removal rate(SRR)of 0.042 mol/cm^(2)/h for CuEDTA at−0.65 V vs SCE(saturated calomel electrode),both of which are much higher than those of the commonly reported electrooxidation technology-based removal systems.Moreover,a proofof-concept CuEDTA/Zn battery with Zn anode and MoS_(2)/GF cathode is demonstrated,which has bifunctions of simultaneous CuEDTA removal and energy output.This is one of the pioneer studies on the electrocatalytic reduction of heavy metal complex and CuEDTA/Zn battery,which brings new insights in developing efficient electrocatalytic reduction system for pollution control and energy output.
基金Key Specialized Research and Development-International Science and Technology Cooperation Program in Henan Province,Grant/Award Number:231111520500Program for Science&Technology Innovation Talents in Universities of Henan Province,Grant/Award Number:24HASTIT009+2 种基金The 111 Project,Grant/Award Number:D17007National Natural Science Foundation of China,Grant/Award Numbers:52072114,52271176Henan Center for Outstanding Overseas Scientists,Grant/Award Number:GZS2022017。
文摘Electrochemical CO_(2) reduction reaction(CO_(2)RR)offers a promising strategy for CO_(2) conversion into value-added C2+products and facilitates the storage of renewable resources under comparatively mild conditions,but still remains a challenge.Herein,we propose the strategy of surface reconstruction and interface integration engineering to construct tuneable Cu^(0)-Cu^(+)-Cu^(2+)sites and oxygen vacancy oxide derived from CeO_(2)/CuO nanosheets(OD-CeO_(2)/CuO NSs)heterojunction catalysts and promote the activity and selectivity of CO_(2)RR.The optimized OD-CeO_(2)/CuO electrocatalyst shows the maximum Faradic efficiencies for C2+products in the H-type cell,which reaches 69.8%at−1.25 V versus a reversible hydrogen electrode(RHE).Advanced characterization analysis and density functional theory(DFT)calculations further confirm the fact that the existence of oxygen vacancies and Cu^(0)-Cu^(+)-Cu^(2+)sites modified with CeO_(2) is conducive to CO_(2) adsorption and activation,enhances the hydrogenation of^(*)CO to^(*)CHO,and further promotes the dimerization of^(*)CHO,thus promoting the selectivity of C2+generation.This facile interface integration and surface reconstruction strategy provides an ideal strategy to guide the design of CO_(2)RR electrocatalysts.
