Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this ...Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this work,a one‐step hydrothermal method was used to manipulate the bimetallic ion intercalation into the interlayer of vanadium oxide.The pre‐intercalated Cu ions act as pillars to pin the vanadium oxide(V‐O)layers,establishing stabilized two‐dimensional channels for fast Zn^(2+) diffusion.The occupation of Mn ions between V‐O interlayer further expands the layer spacing and increases the concentration of oxygen defects(Od),which boosts the Zn^(2+) diffusion kinetics.As a result,as‐prepared Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode shows outstanding Zn‐storage capabilities under room‐and lowtemperature environments(e.g.,440.3 mAh g^(−1) at room temperature and 294.3 mAh g^(−1)at−60°C).Importantly,it shows a long cycling life and high capacity retention of 93.4%over 2500 cycles at 2 A g^(−1) at−60°C.Furthermore,the reversible intercalation chemistry mechanisms during discharging/charging processes were revealed via operando X‐ray powder diffraction and ex situ Raman characterizations.The strategy of a couple of 3d transition metal doping provides a solution for the development of superior room‐/lowtemperature vanadium‐based cathode materials.展开更多
3D flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2)/MoS_(2)Z-scheme layered heterojunction photocatalyst was fabricated by oil bath and hydrothermal methods.The heterojunction with narrow band gap of~1.95 eV exten...3D flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2)/MoS_(2)Z-scheme layered heterojunction photocatalyst was fabricated by oil bath and hydrothermal methods.The heterojunction with narrow band gap of~1.95 eV extended the photoresponse to near-infrared region,which showed obvious photothermal effect due to the introduction of MoS_(2) with broad spectrum response.MoS_(2) nanosheets were anchored onto the surface of flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2) nanosheets,thereby forming efficient layered heterojunctions,the solar-driven photocatalytic efficiency in degradation of highly toxic dichlorophenol and reduction of hexavalent chromium was improved to 98.5%and 99.2%,which was~4 and 7 times higher than that of the pristine Bi_(4)O_(5)I_(2),respectively.In addition,the photocatalytic hydrogen production rate reached 496.78 μmol h^(-1)g^(-1),which was~6 times higher than that of the pristine Bi_(4)O_(5)I_(2).The excellent photocatalytic performance can be ascribed to the promoted photothermal effect,as well as,the formation of compact Z-scheme layered heterojunctions.The 3D flower-like hierarchical mesoporous structure provided adequate surface active-sites,which was conducive to the mass transfer.Moreover,the high stability of the prepared photocatalyst further promoted its potential practical application.This strategy also provides new insights for fabricating layered Zscheme heterojunctions photocatalysts with highly photothermal-photocatalytic efficiency.展开更多
基金National Natural Science Foundation of China,Grant/Award Numbers:52372188,51902090,51922008,520721142023 Introduction of studying abroad talent program,the China Postdoctoral Science Foundation,Grant/Award Number:2019 M652546+3 种基金Xinxiang Major Science and Technology Projects,Grant/Award Number:21ZD001Henan Province Postdoctoral Start‐Up Foundation,Grant/Award Number:1901017Henan Center for Outstanding Overseas Scientists,Grant/Award Number:GZS2018003Overseas Expertise Introduction Project for Discipline Innovation,Grant/Award Number:D17007。
文摘Vanadium oxide cathode materials with stable crystal structure and fast Zn^(2+) storage capabilities are extremely important to achieving outstanding electrochemical performance in aqueous zinc‐ion batteries.In this work,a one‐step hydrothermal method was used to manipulate the bimetallic ion intercalation into the interlayer of vanadium oxide.The pre‐intercalated Cu ions act as pillars to pin the vanadium oxide(V‐O)layers,establishing stabilized two‐dimensional channels for fast Zn^(2+) diffusion.The occupation of Mn ions between V‐O interlayer further expands the layer spacing and increases the concentration of oxygen defects(Od),which boosts the Zn^(2+) diffusion kinetics.As a result,as‐prepared Cu_(0.17)Mn_(0.03)V_(2)O_(5−□)·2.16H_(2)O cathode shows outstanding Zn‐storage capabilities under room‐and lowtemperature environments(e.g.,440.3 mAh g^(−1) at room temperature and 294.3 mAh g^(−1)at−60°C).Importantly,it shows a long cycling life and high capacity retention of 93.4%over 2500 cycles at 2 A g^(−1) at−60°C.Furthermore,the reversible intercalation chemistry mechanisms during discharging/charging processes were revealed via operando X‐ray powder diffraction and ex situ Raman characterizations.The strategy of a couple of 3d transition metal doping provides a solution for the development of superior room‐/lowtemperature vanadium‐based cathode materials.
基金support of this research by the National Natural Science Foundation of China(21871078)the Natural Science Foundation of Heilongjiang Province(JQ2019B001 and B2018010)+3 种基金the Heilongjiang Postdoctoral Startup Fund(LBH-Q14135)the Heilongjiang University Science Fund for Distinguished Young Scholars(JCL201802)the Heilongjiang Provincial Institutions of Higher Learning Basic Research Funds Basic Research Projects(KJCX201909)the Heilongjiang Touyan Innovation Team Program.
文摘3D flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2)/MoS_(2)Z-scheme layered heterojunction photocatalyst was fabricated by oil bath and hydrothermal methods.The heterojunction with narrow band gap of~1.95 eV extended the photoresponse to near-infrared region,which showed obvious photothermal effect due to the introduction of MoS_(2) with broad spectrum response.MoS_(2) nanosheets were anchored onto the surface of flower-like hierarchical mesoporous Bi_(4)O_(5)I_(2) nanosheets,thereby forming efficient layered heterojunctions,the solar-driven photocatalytic efficiency in degradation of highly toxic dichlorophenol and reduction of hexavalent chromium was improved to 98.5%and 99.2%,which was~4 and 7 times higher than that of the pristine Bi_(4)O_(5)I_(2),respectively.In addition,the photocatalytic hydrogen production rate reached 496.78 μmol h^(-1)g^(-1),which was~6 times higher than that of the pristine Bi_(4)O_(5)I_(2).The excellent photocatalytic performance can be ascribed to the promoted photothermal effect,as well as,the formation of compact Z-scheme layered heterojunctions.The 3D flower-like hierarchical mesoporous structure provided adequate surface active-sites,which was conducive to the mass transfer.Moreover,the high stability of the prepared photocatalyst further promoted its potential practical application.This strategy also provides new insights for fabricating layered Zscheme heterojunctions photocatalysts with highly photothermal-photocatalytic efficiency.
