Designing efficient and long-lasting non-metal electrocatalysts is an urgent task for addressing the issue of kinetic hysteresis in electrochemical oxidation reactions.The bimetallic hydroxides,catalyzing the oxygen e...Designing efficient and long-lasting non-metal electrocatalysts is an urgent task for addressing the issue of kinetic hysteresis in electrochemical oxidation reactions.The bimetallic hydroxides,catalyzing the oxygen evolution reaction(OER),have significant research potential because hydroxide reconstruction to generate an active phase is a remarkable advantage.Herein,the complete reconstruction of ultrathin CoNi(OH)_(2) nanosheets was achieved by embedding Ag nanoparticles into the hydroxide to induce a spontaneous redox reaction(SRR),forming heterojunction Ag@CoNi(OH)_(2) for bifunctional hydrolysis.Theoretical calculations and in situ Raman and ex situ characterizations revealed that the inductive effect of the Ag cation redistributed the charge to promote phase transformation to highly activate Ag-modified hydroxides.The Co-Ni dual sites in Co/NiOOH serve as novel active sites for optimizing the intermediates,thereby weakening the barrier formed by OOH^*.Ag@CoNi(OH)_(2) required a potential of 1.55 V to drive water splitting at a current density of 10 mA cm^(-2),with nearly 98.6% Faraday efficiency.Through ion induction and triggering of electron regulation in the OER via the synergistic action of the heterogeneous interface and surface reconstruction,this strategic design can overcome the limited capacity of bimetallic hydroxides and bridge the gap between the basic theory and industrialization of water decomposition.展开更多
Transition metal chalcogenides(TMCs)are a category of electrocatalysts with favorable catalytic activity,however,the impact of oxidation and the leaching of chalcogens on the urea oxidation reaction(UOR)is not clear.H...Transition metal chalcogenides(TMCs)are a category of electrocatalysts with favorable catalytic activity,however,the impact of oxidation and the leaching of chalcogens on the urea oxidation reaction(UOR)is not clear.Herein,3D nanostructures of Mo-Ni_(3)S_(2) nanowire arrays densely grown on nickel foam(NF)were conceived and produced using a hydrothermal treatment.During the UOR process,S and Mo are electrooxidized to generate sulfite(SO_(3)^(2-))and molybdate(MoO_(4)^(2-)),with SO_(3)^(2-)further oxidized to sulfate(SO_(4)^(2-)).Experiments proved that adding molybdate and sulfate actively improves the oxidation activity of Ni(OH)_(2) and optimizes the adsorption/desorption of the UOR intermediates.The well-conceived Mo-Ni_(3)S_(2) bifunctional catalyst performs well in urea-aided hydrolysis at up to 82 mA cm^(-2) at a voltage of 1.57 V with little performance degradation over 50 h.A promising avenue for new insights into the mechanisms underlying anionic surface reconstruction in the UOR process is offered in this work.展开更多
Efficient and affordable electrocatalysts are crucial for advancing hydrogen energy.Water electrolysis for hydrogen production is the dominant energy conversion method.However,the oxygen evolution reaction(OER)faces c...Efficient and affordable electrocatalysts are crucial for advancing hydrogen energy.Water electrolysis for hydrogen production is the dominant energy conversion method.However,the oxygen evolution reaction(OER)faces challenges due to high activation energy.Unlike sulfides and selenides,transition metal tellurides exhibit a superior conductivity and mass transport rate.Interfacial engineering is a potential solution due to its ability to modulate physical and chemical properties.However,research on interfacial engineering for the OER remains limited.This study employed a hydrothermal method to prepare cobalt telluride(CoTe)nanoarrays supported by nickel foam.Additionally,the fast interfacial method was utilized to construct a CoTe@FeOOH nanointerface.The coupling of CoTe and FeOOH significantly enhanced the catalytic activity for the OER.The results show that CoTe@FeOOH exhibited favorable performance with a Tafel slope of up to 69.9 mV dec^(-1) and a low overpotential of 325 mV at 100 mA cm^(-2).Theoretical calculations indicated that a heterogeneous interface comprised of FeOOH and CoTe can surmount the reaction energy barriers of intermediates in the OER process.CoTe@FeOOH’s small size,heterogeneous structure,and synergistic effects can be fully exploited,providing valuable insights into the design of innovative electrocatalysts.展开更多
基金supported by the Inner Mongolia R&D Program Plan(2021ZD0042,2021EEDSCXSFQZD006)the National Natural Science Foundation of China(21902123)the Natural Science Basic Research Program of Shaanxi(2023-JC-ZD-22)。
文摘Designing efficient and long-lasting non-metal electrocatalysts is an urgent task for addressing the issue of kinetic hysteresis in electrochemical oxidation reactions.The bimetallic hydroxides,catalyzing the oxygen evolution reaction(OER),have significant research potential because hydroxide reconstruction to generate an active phase is a remarkable advantage.Herein,the complete reconstruction of ultrathin CoNi(OH)_(2) nanosheets was achieved by embedding Ag nanoparticles into the hydroxide to induce a spontaneous redox reaction(SRR),forming heterojunction Ag@CoNi(OH)_(2) for bifunctional hydrolysis.Theoretical calculations and in situ Raman and ex situ characterizations revealed that the inductive effect of the Ag cation redistributed the charge to promote phase transformation to highly activate Ag-modified hydroxides.The Co-Ni dual sites in Co/NiOOH serve as novel active sites for optimizing the intermediates,thereby weakening the barrier formed by OOH^*.Ag@CoNi(OH)_(2) required a potential of 1.55 V to drive water splitting at a current density of 10 mA cm^(-2),with nearly 98.6% Faraday efficiency.Through ion induction and triggering of electron regulation in the OER via the synergistic action of the heterogeneous interface and surface reconstruction,this strategic design can overcome the limited capacity of bimetallic hydroxides and bridge the gap between the basic theory and industrialization of water decomposition.
基金supported by the Natural Science Basic Research Program of Shaanxi(Program No.2023-JC-ZD-22)the Scientific Research Startup Program for Introduced Talents of Shaanxi University of Technology(SLGRCQD2303)the National Natural Science Foundation of China(Grant No.22469018).
文摘Transition metal chalcogenides(TMCs)are a category of electrocatalysts with favorable catalytic activity,however,the impact of oxidation and the leaching of chalcogens on the urea oxidation reaction(UOR)is not clear.Herein,3D nanostructures of Mo-Ni_(3)S_(2) nanowire arrays densely grown on nickel foam(NF)were conceived and produced using a hydrothermal treatment.During the UOR process,S and Mo are electrooxidized to generate sulfite(SO_(3)^(2-))and molybdate(MoO_(4)^(2-)),with SO_(3)^(2-)further oxidized to sulfate(SO_(4)^(2-)).Experiments proved that adding molybdate and sulfate actively improves the oxidation activity of Ni(OH)_(2) and optimizes the adsorption/desorption of the UOR intermediates.The well-conceived Mo-Ni_(3)S_(2) bifunctional catalyst performs well in urea-aided hydrolysis at up to 82 mA cm^(-2) at a voltage of 1.57 V with little performance degradation over 50 h.A promising avenue for new insights into the mechanisms underlying anionic surface reconstruction in the UOR process is offered in this work.
基金supported by the Natural Science Basic Research Program of Shaanxi(program no.2023-JC-ZD-22)the National Natural Science Foundation of China(no.22179074)the Young Talent Fund of Xi’an Association for Science and Technology.
文摘Efficient and affordable electrocatalysts are crucial for advancing hydrogen energy.Water electrolysis for hydrogen production is the dominant energy conversion method.However,the oxygen evolution reaction(OER)faces challenges due to high activation energy.Unlike sulfides and selenides,transition metal tellurides exhibit a superior conductivity and mass transport rate.Interfacial engineering is a potential solution due to its ability to modulate physical and chemical properties.However,research on interfacial engineering for the OER remains limited.This study employed a hydrothermal method to prepare cobalt telluride(CoTe)nanoarrays supported by nickel foam.Additionally,the fast interfacial method was utilized to construct a CoTe@FeOOH nanointerface.The coupling of CoTe and FeOOH significantly enhanced the catalytic activity for the OER.The results show that CoTe@FeOOH exhibited favorable performance with a Tafel slope of up to 69.9 mV dec^(-1) and a low overpotential of 325 mV at 100 mA cm^(-2).Theoretical calculations indicated that a heterogeneous interface comprised of FeOOH and CoTe can surmount the reaction energy barriers of intermediates in the OER process.CoTe@FeOOH’s small size,heterogeneous structure,and synergistic effects can be fully exploited,providing valuable insights into the design of innovative electrocatalysts.
