Development of cost-effective,active and durable electrocatalysts for overall water splitting is still a huge challenge.Herein,we have constructed one-dimensional(1D)cobalt sulfide and vanadium sulfide heterojunction ...Development of cost-effective,active and durable electrocatalysts for overall water splitting is still a huge challenge.Herein,we have constructed one-dimensional(1D)cobalt sulfide and vanadium sulfide heterojunction nanowires arranged on carbon cloth(Co_(9)S_(8)-V_(3)S_(4)/CC)as bifunctional electrocatalysts for the efficient overall water splitting.The 1D wire-structured Co_(9)S_(8)-V_(3)S_(4)heterojunctions possess large surface area,plentiful active sites and rapid transport of electrons/reactants and the release of gas.Importantly,the electron transfer from Co9S8 to V3S4 occurs at the interface due to the strong electronic coupling effect in Co_(9)S_(8)-V_(3)S_(4)heterojunction,in which the electron-attracting V3S4(V2^(+))optimizes the adsorption of H*active species for hydrogen evolution reaction(HER),while the electron-losing Co9S8(Co3+)responds to the enhancement of oxygen evolution reaction(OER)activity.Co_(9)S_(8)-V_(3)S_(4)/CC exhibits low overpotentials of 85 and 232 mV at 10 mA cm^(−2)and small Tafel slopes of 51 and 59 mV dec^(−1)for HER and OER,respectively.Especially,the electrolyzer with Co_(9)S_(8)-V_(3)S_(4)/CC as both the anode and cathode requires low onset voltage of 1.35 V and cell voltage of 1.53 V at 10 mA cm^(−2)and exhibits high Faradaic efficiencies and robust stability.It can be driven by a solar cell(1.53 V)for continuous production of hydrogen and oxygen.This study highlights the design of 1D sulfide heterojunction in pursuit of highly efficient electrocatalysts for overall water splitting.展开更多
The development of effective and low-cost catalysts for overall water splitting is essential for clean production of hydrogen from water.In this paper,we report the synthesis of cobalt-vanadium（Co-V）bimetal-based ca...The development of effective and low-cost catalysts for overall water splitting is essential for clean production of hydrogen from water.In this paper,we report the synthesis of cobalt-vanadium（Co-V）bimetal-based catalysts for the effective water splitting.The Co_2V_2O_7·xH_2O nanoplates containing both Co and V elements were selected as the precursors.After the calcination under NH_3atmosphere,the Co_2VO_4and Co/VN could be obtained just by tuning the calcination temperature.Electrochemical tests indicated that the Co-V bimetal-based materials could be used as active hydrogen evolution reaction（HER）and oxygen evolution reaction（OER）catalyst by regulating their structure.The Co/VN showed good performance for HER with the onset potential of68 mV and can achieve a current density of 10 mA cm^（-2）at an overpotential of 92 m V.Meanwhile,the Co_2VO_4exhibited the obvious OER performance with overpotential of 300 mV to achieve a current density of 10 mA cm^（-2）.When the Co_2VO_4and Co/VN were used as the anode and cathode in a twoelectrode system,respectively,the cell needed a voltage of1.65 V to achieve 10 mA cm^（-2）together with good stability.This work would be indicative to constructing Co-V bimetalbased catalysts for the catalytic application.展开更多
Multi-interface engineering is deemed as an effective strategy to boost catalytic activity via electronic structure modulation. However, it is still a big challenge due to the phase-separation tendency. Herein, we des...Multi-interface engineering is deemed as an effective strategy to boost catalytic activity via electronic structure modulation. However, it is still a big challenge due to the phase-separation tendency. Herein, we designed CoP-WP heterojunctions with multi-touch interfaces using Co_(8)W_(18), a definite structure polyoxometalate-based polynuclear cobalt molecular cluster, as a precursor. The Co P-WP heterojunctions anchored on reduced graphene oxide(Co P-WP/r GO)were obtained by growing Co_(8)W_(18)on GO followed by phosphorization. The intrinsic {Co-O-W} coordination modes in Co_(8)W_(18)are conducive to the formation of the multiple interfaces between CoP and WP. The abundant intimate interfaces in Co P-WP heterojunctions promote the electron transfer from WP to Co P, thus regulating the interfacial electronic structure and optimizing the hydrogen adsorption free energy(ΔGH*), as verified by X-ray photoelectron spectroscopy analysis and theoretical calculations. Furthermore, the integration of r GO provides Co P-WP/r GO with a large surface area and high conductivity, aiding mass transport and charge transfer. Co P-WP/r GO exhibits remarkable hydrogen evolution reaction(HER) activity with low overpotentials of 96, 130,and 138 m V at 10 m A cm^(-2)in alkaline, acidic and neutral media, respectively, and has long-term durability. Our discovery provides an opportunity to design heterojunction materials with multi-coupled interfaces at low-cost and efficient HER catalysts.展开更多
基金supported by the National Key R&D Program of China (2018YFB1502401)the National Natural Science Foundation of China (21631004, 21805073, 2161055 and 21901064)+3 种基金the Natural Science Foundation of Heilongjiang Province (QC2018014)the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province (UNPYSCT-2017123 and UNPYSCT-2017118)the Basic Research Fund of Heilongjiang University in Heilongjiang Province (RCYJTD201801)Heilongjiang University Excellent Youth Foundation
文摘Development of cost-effective,active and durable electrocatalysts for overall water splitting is still a huge challenge.Herein,we have constructed one-dimensional(1D)cobalt sulfide and vanadium sulfide heterojunction nanowires arranged on carbon cloth(Co_(9)S_(8)-V_(3)S_(4)/CC)as bifunctional electrocatalysts for the efficient overall water splitting.The 1D wire-structured Co_(9)S_(8)-V_(3)S_(4)heterojunctions possess large surface area,plentiful active sites and rapid transport of electrons/reactants and the release of gas.Importantly,the electron transfer from Co9S8 to V3S4 occurs at the interface due to the strong electronic coupling effect in Co_(9)S_(8)-V_(3)S_(4)heterojunction,in which the electron-attracting V3S4(V2^(+))optimizes the adsorption of H*active species for hydrogen evolution reaction(HER),while the electron-losing Co9S8(Co3+)responds to the enhancement of oxygen evolution reaction(OER)activity.Co_(9)S_(8)-V_(3)S_(4)/CC exhibits low overpotentials of 85 and 232 mV at 10 mA cm^(−2)and small Tafel slopes of 51 and 59 mV dec^(−1)for HER and OER,respectively.Especially,the electrolyzer with Co_(9)S_(8)-V_(3)S_(4)/CC as both the anode and cathode requires low onset voltage of 1.35 V and cell voltage of 1.53 V at 10 mA cm^(−2)and exhibits high Faradaic efficiencies and robust stability.It can be driven by a solar cell(1.53 V)for continuous production of hydrogen and oxygen.This study highlights the design of 1D sulfide heterojunction in pursuit of highly efficient electrocatalysts for overall water splitting.
基金supported by the Key Program Projects of the National Natural Science Foundation of China (21631004)the National Natural Science Foundation of China (21601055, 21571054 and 21401048)+1 种基金the Natural Science Foundation of Heilongjiang Province (B2017008)Heilongjiang University Excellent Youth Foundation
文摘The development of effective and low-cost catalysts for overall water splitting is essential for clean production of hydrogen from water.In this paper,we report the synthesis of cobalt-vanadium（Co-V）bimetal-based catalysts for the effective water splitting.The Co_2V_2O_7·xH_2O nanoplates containing both Co and V elements were selected as the precursors.After the calcination under NH_3atmosphere,the Co_2VO_4and Co/VN could be obtained just by tuning the calcination temperature.Electrochemical tests indicated that the Co-V bimetal-based materials could be used as active hydrogen evolution reaction（HER）and oxygen evolution reaction（OER）catalyst by regulating their structure.The Co/VN showed good performance for HER with the onset potential of68 mV and can achieve a current density of 10 mA cm^（-2）at an overpotential of 92 m V.Meanwhile,the Co_2VO_4exhibited the obvious OER performance with overpotential of 300 mV to achieve a current density of 10 mA cm^（-2）.When the Co_2VO_4and Co/VN were used as the anode and cathode in a twoelectrode system,respectively,the cell needed a voltage of1.65 V to achieve 10 mA cm^（-2）together with good stability.This work would be indicative to constructing Co-V bimetalbased catalysts for the catalytic application.
基金financially supported by the National Key R&D Program of China (2018YFB1502401)the National Natural Science Foundation of China (91961111, 22171074, 21601055, U20A20250, 21805073, and 22005161)+3 种基金the Natural Science Foundation of Heilongjiang Province (ZD2021B003)China Postdoctoral Science Foundation (2017M611406)the Postdoctoral Science Foundation of Heilongjiang Province (LBH-Z16175)the Scientific Research Funds of University Affiliated to Heilongjiang Province (KJCX201913)。
文摘Multi-interface engineering is deemed as an effective strategy to boost catalytic activity via electronic structure modulation. However, it is still a big challenge due to the phase-separation tendency. Herein, we designed CoP-WP heterojunctions with multi-touch interfaces using Co_(8)W_(18), a definite structure polyoxometalate-based polynuclear cobalt molecular cluster, as a precursor. The Co P-WP heterojunctions anchored on reduced graphene oxide(Co P-WP/r GO)were obtained by growing Co_(8)W_(18)on GO followed by phosphorization. The intrinsic {Co-O-W} coordination modes in Co_(8)W_(18)are conducive to the formation of the multiple interfaces between CoP and WP. The abundant intimate interfaces in Co P-WP heterojunctions promote the electron transfer from WP to Co P, thus regulating the interfacial electronic structure and optimizing the hydrogen adsorption free energy(ΔGH*), as verified by X-ray photoelectron spectroscopy analysis and theoretical calculations. Furthermore, the integration of r GO provides Co P-WP/r GO with a large surface area and high conductivity, aiding mass transport and charge transfer. Co P-WP/r GO exhibits remarkable hydrogen evolution reaction(HER) activity with low overpotentials of 96, 130,and 138 m V at 10 m A cm^(-2)in alkaline, acidic and neutral media, respectively, and has long-term durability. Our discovery provides an opportunity to design heterojunction materials with multi-coupled interfaces at low-cost and efficient HER catalysts.
