The development of highly efficient and stable electrocatalysts for the hydrogen evolution reaction(HER)under alkaline media is of great importance due to its sluggish water dissociation kinetics.In this work,ultrafin...The development of highly efficient and stable electrocatalysts for the hydrogen evolution reaction(HER)under alkaline media is of great importance due to its sluggish water dissociation kinetics.In this work,ultrafine Rh nanoparticle decorated MoSe_(2)nanoflowers have been synthesized through a colloidal synthetic method.When further used as electrocatalysts for HER in alkaline media,the experimental results demonstrate that 8.2%Rh–MoSe_(2)nanoflowers exhibit excellent catalytic activity with a small overpotential of 73 mV to obtain the current density of 10 mA cm^(−2)with good stability.展开更多
Nonprecious NiMo composites are promising hydrogen evolution reaction electrocatalysts due to their Pt-like catalytic surfaces.However,because of hydroxide adsorption in alkaline media,the oxidative elution of Mo dete...Nonprecious NiMo composites are promising hydrogen evolution reaction electrocatalysts due to their Pt-like catalytic surfaces.However,because of hydroxide adsorption in alkaline media,the oxidative elution of Mo deteriorates structural and catalytic stability.Herein,a Cu and Co incorporated NiMo composite(NiMoCuCo)is prepared as an active and durable hydrogen evolution reaction(HER)electrocatalyst by direct electrochemical deposition.The low electronegativities of Cu and Co effectively reduce the charge valence state of the metals and the zeta potential of the electrocatalysts,ameliorating surface electronegativity.NiMoCuCo shows a low overpotential of 53 mV at a current density of 10 mA cm^(-2) and a slight overpotential increase of 0.01 mV h^(-1)(1.8%)after a long-term stability test for 100 h at a current density of 100 mA cm^(-2),outperforming NiMo and NiMoCu.Ex situ analyses demonstrate that NiMoCuCo exhibits a reduced charge valence state of Mo without significant degradation after the long-term stability test.Furthermore,Co in NiMoCuCo acts as the OH adsorption site on behalf of Mo,owing to the reduced surface electronegativity of Mo and strong OH affinity.This results in a balance between water dissociation and HER kinetics of NiMo composites,leading to excellent HER activity and stability.展开更多
It is highly attractive to develop high-performance non-noble-metal electrocatalysts for water oxidation in alkaline media.In this communication,we report the hydrothermal growth of a Co-MOF nanosheet array on Ni foam...It is highly attractive to develop high-performance non-noble-metal electrocatalysts for water oxidation in alkaline media.In this communication,we report the hydrothermal growth of a Co-MOF nanosheet array on Ni foam(Co-MOF/NF)as a 3D oxygen evolution reaction catalyst in alkaline media.The Co-MOF/NF demonstrates superior activity and needs an overpotential of only 311 mV to drive a geometrical catalytic current density of 50 mA cm^(-2)in 1.0 M KOH.展开更多
The exploration of efficient and durative bifunctional electrocatalysts for overall water splitting(OWS)is critical for hydrogen production in clean energy applications.Herein,a novel double-sandwiched architecture of...The exploration of efficient and durative bifunctional electrocatalysts for overall water splitting(OWS)is critical for hydrogen production in clean energy applications.Herein,a novel double-sandwiched architecture of reduced graphene oxide(rGO),cobalt silicate(CS),and cobalt–iron phosphides,denoted as rGO/CS/(Co,Fe)ₓPᵧ,is designed to enhance both the oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)in alkaline media.The formation of Co₂P and Fe₂P on rGO/CS not only protects the silicate from alkaline corrosion,but also generates dual-active centers that synergistically improve the conductivity and catalytic activity.Multiple interface coupling between rGO,CS,and(Co,Fe)ₓPᵧ triggers a built-in electric field,which significantly enhances charge separation,electron transport,and reaction kinetics.This built-in electric field lowers the energy barrier for HER by facilitating H–OH bond dissociation and accelerates the OER by promoting OH⁻adsorption.The rGO/CS/(Co,Fe)ₓPᵧ catalyst achieves overpotentials of 256 mV(OER)and 180 mV(HER)at 10 mA cm⁻²,surpassing most reported catalysts and rivaling commercial Pt/C and RuO₂.Furthermore,the rGO/CS/(Co,Fe)ₓPᵧ(+/−) demonstrates a low OWS voltage of 1.41 V.The current work provides a new approach to catalyst design through interface engineering and electric field optimization,offering a scalable solution for sustainable hydrogen production.展开更多
Nickel-based oxygen evolution reaction(OER)electrocatalysts have garnered significant attention due to their high catalytic activity and abundant reserves.In this study,we report a series of cucurbit[n]uril(CB[n],n=5-...Nickel-based oxygen evolution reaction(OER)electrocatalysts have garnered significant attention due to their high catalytic activity and abundant reserves.In this study,we report a series of cucurbit[n]uril(CB[n],n=5-8)functionalized Ni nanocomposites(CB[n]-Ni,n=5-8)to synergistically enhance the OER catalytic activity in alkaline media.The sizes and electronic structures of CB[n]-Ni can be precisely controlled using CB[n]with varying cavity sizes.Among these CB[n]-Ni nanocomposites,CB[7]-Ni presented superior OER performance compared to other CB[n]-Ni(n=5,6,and 8)and CB-free Ni nanocomposites.Operando electrochemical impedance spectroscopy(EIS)studies demonstrated that CB[7]-Ni initiated the OER at a relatively low applied potential of 1.5 V vs.RHE,achieving a superior turnover frequency of 0.24 s^(−1) at 1.55 V vs.RHE.Additionally,spectroscopic measurements and theoretical calculations revealed that the incorporation of CB[7]regulates the electronic structure of the active Ni nanocomposite and lowers the activation energy for the formation of the*OOH intermediate,thereby facilitating the OER process.This work not only broadens the application of supramolecular macrocycles in electrocatalysis but also provides a novel strategy for the design of electrocatalysts.展开更多
基金financially supported by the National Natural Science Foundation of China(21571145,21633008)Largescale Largescale Instrument and Equipment Sharing Foundation of Wuhan University.
文摘The development of highly efficient and stable electrocatalysts for the hydrogen evolution reaction(HER)under alkaline media is of great importance due to its sluggish water dissociation kinetics.In this work,ultrafine Rh nanoparticle decorated MoSe_(2)nanoflowers have been synthesized through a colloidal synthetic method.When further used as electrocatalysts for HER in alkaline media,the experimental results demonstrate that 8.2%Rh–MoSe_(2)nanoflowers exhibit excellent catalytic activity with a small overpotential of 73 mV to obtain the current density of 10 mA cm^(−2)with good stability.
基金supported by the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(RS-2024-00344256)supported by the Nano&Material Technology Development Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(RS-2024-00446825)supported by the Soonchunhyang University Research Fund.
文摘Nonprecious NiMo composites are promising hydrogen evolution reaction electrocatalysts due to their Pt-like catalytic surfaces.However,because of hydroxide adsorption in alkaline media,the oxidative elution of Mo deteriorates structural and catalytic stability.Herein,a Cu and Co incorporated NiMo composite(NiMoCuCo)is prepared as an active and durable hydrogen evolution reaction(HER)electrocatalyst by direct electrochemical deposition.The low electronegativities of Cu and Co effectively reduce the charge valence state of the metals and the zeta potential of the electrocatalysts,ameliorating surface electronegativity.NiMoCuCo shows a low overpotential of 53 mV at a current density of 10 mA cm^(-2) and a slight overpotential increase of 0.01 mV h^(-1)(1.8%)after a long-term stability test for 100 h at a current density of 100 mA cm^(-2),outperforming NiMo and NiMoCu.Ex situ analyses demonstrate that NiMoCuCo exhibits a reduced charge valence state of Mo without significant degradation after the long-term stability test.Furthermore,Co in NiMoCuCo acts as the OH adsorption site on behalf of Mo,owing to the reduced surface electronegativity of Mo and strong OH affinity.This results in a balance between water dissociation and HER kinetics of NiMo composites,leading to excellent HER activity and stability.
基金supported by the National Natural Science Foundation of China(No.21775089,21375076)the Key Research and Development Program of Shandong Province(2015GSF121031)the Natural Science Foundation Projects of Shandong Province(No.ZR2017JL010,ZR2017QB008,ZR2017LEE006).
文摘It is highly attractive to develop high-performance non-noble-metal electrocatalysts for water oxidation in alkaline media.In this communication,we report the hydrothermal growth of a Co-MOF nanosheet array on Ni foam(Co-MOF/NF)as a 3D oxygen evolution reaction catalyst in alkaline media.The Co-MOF/NF demonstrates superior activity and needs an overpotential of only 311 mV to drive a geometrical catalytic current density of 50 mA cm^(-2)in 1.0 M KOH.
基金Fund of Hubei University of Science and Technology(BK202504)the Natural Science Foundation of Liaoning Province(2023-MS-115)for supporting this work+1 种基金the National Natural Science Foundation of China(22305028)the Dalian Minzu University Doctoral Program(120164)for supporting this work。
文摘The exploration of efficient and durative bifunctional electrocatalysts for overall water splitting(OWS)is critical for hydrogen production in clean energy applications.Herein,a novel double-sandwiched architecture of reduced graphene oxide(rGO),cobalt silicate(CS),and cobalt–iron phosphides,denoted as rGO/CS/(Co,Fe)ₓPᵧ,is designed to enhance both the oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)in alkaline media.The formation of Co₂P and Fe₂P on rGO/CS not only protects the silicate from alkaline corrosion,but also generates dual-active centers that synergistically improve the conductivity and catalytic activity.Multiple interface coupling between rGO,CS,and(Co,Fe)ₓPᵧ triggers a built-in electric field,which significantly enhances charge separation,electron transport,and reaction kinetics.This built-in electric field lowers the energy barrier for HER by facilitating H–OH bond dissociation and accelerates the OER by promoting OH⁻adsorption.The rGO/CS/(Co,Fe)ₓPᵧ catalyst achieves overpotentials of 256 mV(OER)and 180 mV(HER)at 10 mA cm⁻²,surpassing most reported catalysts and rivaling commercial Pt/C and RuO₂.Furthermore,the rGO/CS/(Co,Fe)ₓPᵧ(+/−) demonstrates a low OWS voltage of 1.41 V.The current work provides a new approach to catalyst design through interface engineering and electric field optimization,offering a scalable solution for sustainable hydrogen production.
基金supported by the National Natural Science Foundation of China(52362028)Guizhou Provincial Basic Research Program(Natural Science)([2023]042)support from the Natural Science Research Project of the Education Department of Guizhou Province(QJJ[2022]001).
文摘Nickel-based oxygen evolution reaction(OER)electrocatalysts have garnered significant attention due to their high catalytic activity and abundant reserves.In this study,we report a series of cucurbit[n]uril(CB[n],n=5-8)functionalized Ni nanocomposites(CB[n]-Ni,n=5-8)to synergistically enhance the OER catalytic activity in alkaline media.The sizes and electronic structures of CB[n]-Ni can be precisely controlled using CB[n]with varying cavity sizes.Among these CB[n]-Ni nanocomposites,CB[7]-Ni presented superior OER performance compared to other CB[n]-Ni(n=5,6,and 8)and CB-free Ni nanocomposites.Operando electrochemical impedance spectroscopy(EIS)studies demonstrated that CB[7]-Ni initiated the OER at a relatively low applied potential of 1.5 V vs.RHE,achieving a superior turnover frequency of 0.24 s^(−1) at 1.55 V vs.RHE.Additionally,spectroscopic measurements and theoretical calculations revealed that the incorporation of CB[7]regulates the electronic structure of the active Ni nanocomposite and lowers the activation energy for the formation of the*OOH intermediate,thereby facilitating the OER process.This work not only broadens the application of supramolecular macrocycles in electrocatalysis but also provides a novel strategy for the design of electrocatalysts.
