Direct seawater electrolysis is a promising way for hydrogen energy production.However,developing efficient and cost-effective electrocatalysts remains a significant challenge for seawater electrolysis with industrial...Direct seawater electrolysis is a promising way for hydrogen energy production.However,developing efficient and cost-effective electrocatalysts remains a significant challenge for seawater electrolysis with industrial-level current density due to high concentration of salts and compete reaction of chlorine evolution.Herein,a 1D NiFe_(2)O_(4)/NiMoO_(4) heterostructure as a bifunctional electrocatalyst for overall seawater splitting is constructed by combining NiMoO_(4) nanowires with NiFe_(2)O_(4)nanoparticles on carbon felt(CF)by a simple hydrothermal,impregnation and calcination method.The electrocatalyst exhibits low overpotential of 237 and 292 mV for oxygen evolution reaction and hydrogen evolution reaction at 400 m A/cm^(2)in the alkaline seawater(1 mol/L KOH+0.5 mol/L NaCl)due to the plentiful interfaces of NiFe_(2)O_(4)/NiMoO_4 which exposes more active sites and expands the active surface area,thereby enhancing its intrinsic activity and promoting the reaction kinetics.Notably,it displays low voltages of 1.95 V to drive current density of 400 m A/cm^(2)in alkaline seawater with its excellent stability of 200 h at above 100 m A/cm^(2),exhibiting outstanding performance and good corrosion resistance.This work provides an effective strategy for constructing efficient and cost-effective electrocatalysts for industrial seawater electrolysis,underscoring its potential for sustainable energy applications.展开更多
The electrochemical oxidation of 5-hydroxymethylfurfural(HMF)to valuable chemicals is an efficient way to upgrade biomass molecules and replace traditional catalytic synthesis.It is crucial to develop efficient and lo...The electrochemical oxidation of 5-hydroxymethylfurfural(HMF)to valuable chemicals is an efficient way to upgrade biomass molecules and replace traditional catalytic synthesis.It is crucial to develop efficient and low-cost earth-abundant electrocatalysts to enhance catalytic performance of HMF oxidation.Herein,a new type of two-dimensional(2D)hybrid arrays consisting of Ni Fe layered double hydroxides(LDH)nanosheets and bimetallic sulfide(Ni Fe S)is constructed via interface engineering for efficient electrocatalytic oxidation of HMF to 2,5-furandicarboxylic acid(FDCA).The preparation process of 2D Ni Fe LDH/NiFeS with ultrathin heterostructure involves in anchoring a Co-based metal-organic framework(Co MOF)as template onto the carbon cloth(CC)via in-situ growth,formation of NiFe LDH on the surface of Co MOF and subsequent partial sulfidation.The electrocatalyst of Ni Fe LDH/Ni Fe S exhibits outstanding performance towards HMF oxidation,about 98.5%yield for FDCA and 97.2%Faraday efficiency(FE)in the alkaline electrolyte with 10 mmol/L HMF,as well as excellent stability retaining 90.1%FE for FDCA after six cycles test.Moreover,even at an HMF concentration of 100 mmol/L,the yield and FE for FDCA remain high at 83.6%and 93.6%,respectively.These findings highlight that 2D heterostructure containing abundant interfaces between Ni Fe LDH nanosheets and Ni Fe S can enhance the intrinsic activity of LDH and thus promote the oxidation reaction kinetics.Additionally,the synergistic effect of the bimetallic Ni Fe compounds also improved the selectivity of HMF conversion to FDCA.Our present work demonstrates that constructing 2D ultrathin heterostructure of Ni Fe LDH/Ni Fe S is a facile strategy via interface engineering to enhance the intrinsic activity of LDH electrocatalysts,which would open new avenues toward low-cost and advanced 2D nanocatalysts for sustainable energy conversion and electrochemical valorization of biomass derivatives.展开更多
基金supported by the National Natural Science Foundation of China(No.51908408)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(No.2019KJ008)Basic Research Program of Jiangsu Province(No.BK20241845)。
文摘Direct seawater electrolysis is a promising way for hydrogen energy production.However,developing efficient and cost-effective electrocatalysts remains a significant challenge for seawater electrolysis with industrial-level current density due to high concentration of salts and compete reaction of chlorine evolution.Herein,a 1D NiFe_(2)O_(4)/NiMoO_(4) heterostructure as a bifunctional electrocatalyst for overall seawater splitting is constructed by combining NiMoO_(4) nanowires with NiFe_(2)O_(4)nanoparticles on carbon felt(CF)by a simple hydrothermal,impregnation and calcination method.The electrocatalyst exhibits low overpotential of 237 and 292 mV for oxygen evolution reaction and hydrogen evolution reaction at 400 m A/cm^(2)in the alkaline seawater(1 mol/L KOH+0.5 mol/L NaCl)due to the plentiful interfaces of NiFe_(2)O_(4)/NiMoO_4 which exposes more active sites and expands the active surface area,thereby enhancing its intrinsic activity and promoting the reaction kinetics.Notably,it displays low voltages of 1.95 V to drive current density of 400 m A/cm^(2)in alkaline seawater with its excellent stability of 200 h at above 100 m A/cm^(2),exhibiting outstanding performance and good corrosion resistance.This work provides an effective strategy for constructing efficient and cost-effective electrocatalysts for industrial seawater electrolysis,underscoring its potential for sustainable energy applications.
基金supported by the National Natural Science Foundation of China(Nos.51908408,21872104)Natural Science Foundation of Tianjin for Distinguished Young Scholar,China(No.20JCJQJC00150)。
文摘The electrochemical oxidation of 5-hydroxymethylfurfural(HMF)to valuable chemicals is an efficient way to upgrade biomass molecules and replace traditional catalytic synthesis.It is crucial to develop efficient and low-cost earth-abundant electrocatalysts to enhance catalytic performance of HMF oxidation.Herein,a new type of two-dimensional(2D)hybrid arrays consisting of Ni Fe layered double hydroxides(LDH)nanosheets and bimetallic sulfide(Ni Fe S)is constructed via interface engineering for efficient electrocatalytic oxidation of HMF to 2,5-furandicarboxylic acid(FDCA).The preparation process of 2D Ni Fe LDH/NiFeS with ultrathin heterostructure involves in anchoring a Co-based metal-organic framework(Co MOF)as template onto the carbon cloth(CC)via in-situ growth,formation of NiFe LDH on the surface of Co MOF and subsequent partial sulfidation.The electrocatalyst of Ni Fe LDH/Ni Fe S exhibits outstanding performance towards HMF oxidation,about 98.5%yield for FDCA and 97.2%Faraday efficiency(FE)in the alkaline electrolyte with 10 mmol/L HMF,as well as excellent stability retaining 90.1%FE for FDCA after six cycles test.Moreover,even at an HMF concentration of 100 mmol/L,the yield and FE for FDCA remain high at 83.6%and 93.6%,respectively.These findings highlight that 2D heterostructure containing abundant interfaces between Ni Fe LDH nanosheets and Ni Fe S can enhance the intrinsic activity of LDH and thus promote the oxidation reaction kinetics.Additionally,the synergistic effect of the bimetallic Ni Fe compounds also improved the selectivity of HMF conversion to FDCA.Our present work demonstrates that constructing 2D ultrathin heterostructure of Ni Fe LDH/Ni Fe S is a facile strategy via interface engineering to enhance the intrinsic activity of LDH electrocatalysts,which would open new avenues toward low-cost and advanced 2D nanocatalysts for sustainable energy conversion and electrochemical valorization of biomass derivatives.
