Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries.However,the low theoretical capacities,kinetics and stability of...Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries.However,the low theoretical capacities,kinetics and stability of anode materials have limited their developments and commercializations.In this study,we propose a novel method to produce two-dimensional layered bismuth oxide selenium(Bi_(2)O_(2)Se)and reduced graphene oxide(r GO)composites via a one-step hydrothermal method.The volume change caused by phase change during rapid charging and discharging is significantly reduced and the capacity reaches 263.83 m Ah g^(-1)at a current density of 0.5 A g^(-1).The Bi_(2)O_(2)Se/r GO electrode exhibits excellent cycling stability in which the capacity retention rate is 81.04%after 5000 cycles.More importantly,the Bi_(2)O_(2)Se/r GO nanosheet composite is used as the anode electrode material with MnCo_(2)O_(4.5)@Ni(OH)_(2)as the cathode electrode material in aqueous alkaline battery.When the energy density is 76.16 W h kg^(-1),the power density reaches 308.65 W kg^(-1).At a power density of 10.21 k W kg^(-1),the energy density remains as high as 33.86 W h kg^(-1).The results presented here may advance the understanding of the issues facing the development of aqueous battery anode materials.展开更多
Flexible zinc-ion batteries(ZIBs)are promising power sources for portable devices due to their high safety and low production cost.However,the low mass-loading and limited areal capacity of cathode materials are the m...Flexible zinc-ion batteries(ZIBs)are promising power sources for portable devices due to their high safety and low production cost.However,the low mass-loading and limited areal capacity of cathode materials are the major problems blocking the practicability of ZIBs.Herein,a high mass-loading and binder-free flexible vanadium oxide(MCV@CC)cathode with a large areal capacity was fabricated via the bridge effect of MXene.The functional MXene bridge induces the growth of the vanadium oxide active layer on the carbon cloth(CC)flexible substrate.The binder-free cathode can reduce the electrochemically inactive weight of the whole electrode,which enhances the energy density of ZIBs.Consequently,the MCV@CC cathode(mass-loading of∼7 mg cm^(−2))delivers a desirable areal capacity(2.36 mAh cm^(−2))and good cycling stability(capacity retention of 86.1%after 1200 cycles at 10 mA cm^(−2)).Moreover,several ex-situ characterization results indicate that the reaction mechanism upon battery cycling is based on the reversible Zn^(2+)/H^(+)(de)intercalation in the vanadium oxide interlayer.Furthermore,the assembled quasi-solid-state MCV@CC//Zn flexible battery exhibits decent performance at different bending states.Such a bridge effect strategy sheds light on the construction of high mass-loading flexible electrodes for ZIBs applications.展开更多
Image sensing is a critical component of modern machine vision technology development.The traditional silicon-based photodiodes possess inflexible responsivity and energy band structures that are hard to manipulate by...Image sensing is a critical component of modern machine vision technology development.The traditional silicon-based photodiodes possess inflexible responsivity and energy band structures that are hard to manipulate by an external field,limiting the system’s ability to process picture data[1].Additionally,existing memristor arrays can do some computation in hardware but cannot directly respond to optical signals,so it is necessary to use additional image sensors to convert optical signals into electrical signals before implementing further signal processing.As a result of their separate data processing units and image sensors,conventional image sensing systems face problems such as slow operation and excessive power consumption that can result in transmitting and processing huge amounts of duplicate information[2,3].展开更多
基金supported by Fund of National Key Laboratory of Science and Technology on Advanced Composites in Special Environments(Grant No.6142905192507)Shenzhen Science and Technology Plan Supported Project(Grant No.JCYJ20170413105844696)+1 种基金China Scholarship Council(Grant No.201606125092)Singapore Ministry of Education Academic Research Fund Tier 2(MOE2018-T2-2-178)
文摘Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries.However,the low theoretical capacities,kinetics and stability of anode materials have limited their developments and commercializations.In this study,we propose a novel method to produce two-dimensional layered bismuth oxide selenium(Bi_(2)O_(2)Se)and reduced graphene oxide(r GO)composites via a one-step hydrothermal method.The volume change caused by phase change during rapid charging and discharging is significantly reduced and the capacity reaches 263.83 m Ah g^(-1)at a current density of 0.5 A g^(-1).The Bi_(2)O_(2)Se/r GO electrode exhibits excellent cycling stability in which the capacity retention rate is 81.04%after 5000 cycles.More importantly,the Bi_(2)O_(2)Se/r GO nanosheet composite is used as the anode electrode material with MnCo_(2)O_(4.5)@Ni(OH)_(2)as the cathode electrode material in aqueous alkaline battery.When the energy density is 76.16 W h kg^(-1),the power density reaches 308.65 W kg^(-1).At a power density of 10.21 k W kg^(-1),the energy density remains as high as 33.86 W h kg^(-1).The results presented here may advance the understanding of the issues facing the development of aqueous battery anode materials.
基金financially supported by the National Natural Science Foundation of China (Grant No.52072094)the Science Foundation of the National Key Laboratory of Science and Technology on Advanced Composites in Special Environ-ments (Grant No.6142905192507)+1 种基金the Shenzhen Constantly-supported Project for Universities and Colleges in 2021 (Nos.GXWD20201230155427003-20200821232246001)the Science,Technology and Innovation Commission of Shenzhen Municipal-ity (Grant No.CJGJZD20210408092200002).
文摘Flexible zinc-ion batteries(ZIBs)are promising power sources for portable devices due to their high safety and low production cost.However,the low mass-loading and limited areal capacity of cathode materials are the major problems blocking the practicability of ZIBs.Herein,a high mass-loading and binder-free flexible vanadium oxide(MCV@CC)cathode with a large areal capacity was fabricated via the bridge effect of MXene.The functional MXene bridge induces the growth of the vanadium oxide active layer on the carbon cloth(CC)flexible substrate.The binder-free cathode can reduce the electrochemically inactive weight of the whole electrode,which enhances the energy density of ZIBs.Consequently,the MCV@CC cathode(mass-loading of∼7 mg cm^(−2))delivers a desirable areal capacity(2.36 mAh cm^(−2))and good cycling stability(capacity retention of 86.1%after 1200 cycles at 10 mA cm^(−2)).Moreover,several ex-situ characterization results indicate that the reaction mechanism upon battery cycling is based on the reversible Zn^(2+)/H^(+)(de)intercalation in the vanadium oxide interlayer.Furthermore,the assembled quasi-solid-state MCV@CC//Zn flexible battery exhibits decent performance at different bending states.Such a bridge effect strategy sheds light on the construction of high mass-loading flexible electrodes for ZIBs applications.
基金supported by the National Key Laboratory of Science and Technology on Advanced Composites in Special Environments(6142905192507)Shenzhen Science and Technology Plan Supported Project(GXWD20201230155427003-20200821232246001 and JCYJ20170413105844696)+1 种基金China Scholarship Councilfinancial support from the Singapore National Research Foundation Competitive Research Program(NRF-CRP22-2019-0007)。
文摘Image sensing is a critical component of modern machine vision technology development.The traditional silicon-based photodiodes possess inflexible responsivity and energy band structures that are hard to manipulate by an external field,limiting the system’s ability to process picture data[1].Additionally,existing memristor arrays can do some computation in hardware but cannot directly respond to optical signals,so it is necessary to use additional image sensors to convert optical signals into electrical signals before implementing further signal processing.As a result of their separate data processing units and image sensors,conventional image sensing systems face problems such as slow operation and excessive power consumption that can result in transmitting and processing huge amounts of duplicate information[2,3].