Highly active and stable FeOOH cocatalysts are essential for achieving optimal performance of BiVO_(4)(BVO)photoanodes.Despite offering remarkable structural stability,widely used thick FeOOH cocatalysts often suffer ...Highly active and stable FeOOH cocatalysts are essential for achieving optimal performance of BiVO_(4)(BVO)photoanodes.Despite offering remarkable structural stability,widely used thick FeOOH cocatalysts often suffer from insufficient hole transport capability,which hinders the overall activity.The present study demonstrates that a simple photoetching strategy is able to introduce gradient distributed oxygen vacancies(GO_(V))in the thick FeOOH layer and significantly enhances the photogenerated holes transport dynamics.The incorporation of GO_(V)within FeOOH not only realizes the“relay transport”of photogenerated hole through the progressive upward shift of the valence band in the spatial distribution,but also provides abundant oxidation active sites by efficient hole trapping.These improvements effectively improve the oxygen evolution reaction(OER)activities and mitigate photocorrosion by the instantaneous hole extraction.Consequently,the FeOOH-GO_(V)layer enables the BVO/FeOOH-GO_(V)photoanode to achieve an impressive photocurrent density of 5.37 mA cm^(-2)and a robust operational stability up to 160 h at 1.23 VRHE,setting new benchmarks for current density and stability in FeOOH-based BVO photoanodes.This work provides an effective avenue to optimize OER cocatalysts for constructing highly efficient and stable photoelectrochemical water splitting devices.展开更多
Nano-crystalline FeOOH particles （5-10 nm） have been uniformly mixed with electric matrix of single-walled carbon nanotubes （SWNTs） for forming FeOOH/SWNT composite via a facile ultrasonication method. Directly us...Nano-crystalline FeOOH particles （5-10 nm） have been uniformly mixed with electric matrix of single-walled carbon nanotubes （SWNTs） for forming FeOOH/SWNT composite via a facile ultrasonication method. Directly using the FeOOH/SWNT composite （containing 15 wt% SWNTs） as anode material for lithium battery enhances kinetics of the Li＋ insertion/extraction processes, thereby effectively improving re- versible capacity and cycle performance, which delivers a high reversible capacity of 758 mAh.g-1 under a current density of 400 mA.g-1 even after 180 cycles, being comparable with previous reports in terms of electrochemical performance for FeOOH anode. The good electrochemical performance should be ascribed to the small particle size and nano-crystalline of FeOOH, as well as the good electronic conductivity of SWNT matrix.展开更多
Aqueous rechargeable Ni-Fe batteries exhibit unique advantages in large-scale energy storage thanks to their affordability,safety,and reliability.However,their limited energy density and Coulombic efficiency stem from...Aqueous rechargeable Ni-Fe batteries exhibit unique advantages in large-scale energy storage thanks to their affordability,safety,and reliability.However,their limited energy density and Coulombic efficiency stem from unfavorable OH^(−)adsorption capability and low electrochemical activity of Fe sites,result in electrode kinetic delays for Fe anodes.Here,we report Mn and S co-modified FeOOH(MSFF)nanosheets as an advanced anode in Ni-Fe batteries,synthesized from a facile one-step surface-redox-etching method at room temperature.Based on the strong electronic coupling effect between Mn and S atoms,such MSFF anode presents fast electron transport capability,enhanced OH^(−)-adsorption capability,and redox reactivity.Specifically,the MSFF anode can achieve a high areal capacity of 2 mAh cm^(−2)at 10 mA cm^(−2),which retains a staggering 96%of the initial capacity after undergoing 9000 cycles at a higher current density of 30 mA cm^(−2).In addition,the assembled Ni-Fe battery can provide a capacity of 0.85 mAh cm^(−2)at 16 mA cm^(−2),significantly outperforming most recently reported aqueous rechargeable batteries.This work may offer an innovative and feasible approach for modulating the local electronic structure of high-performance Ni-Fe battery electrode materials.展开更多
基金supported by the State Key Laboratory of Solidification Processing in NWPU(SKLSP202407)the National Natural Science Foundation of China(52402130)+2 种基金the Natural Science Basis Research Plan in Shaanxi Province of China(2024JC-YBQN-0384)the Shaanxi Science and Technology Innovation Team(2023-CX-TD-44)the National Natural Science Foundation of China(52301015).
文摘Highly active and stable FeOOH cocatalysts are essential for achieving optimal performance of BiVO_(4)(BVO)photoanodes.Despite offering remarkable structural stability,widely used thick FeOOH cocatalysts often suffer from insufficient hole transport capability,which hinders the overall activity.The present study demonstrates that a simple photoetching strategy is able to introduce gradient distributed oxygen vacancies(GO_(V))in the thick FeOOH layer and significantly enhances the photogenerated holes transport dynamics.The incorporation of GO_(V)within FeOOH not only realizes the“relay transport”of photogenerated hole through the progressive upward shift of the valence band in the spatial distribution,but also provides abundant oxidation active sites by efficient hole trapping.These improvements effectively improve the oxygen evolution reaction(OER)activities and mitigate photocorrosion by the instantaneous hole extraction.Consequently,the FeOOH-GO_(V)layer enables the BVO/FeOOH-GO_(V)photoanode to achieve an impressive photocurrent density of 5.37 mA cm^(-2)and a robust operational stability up to 160 h at 1.23 VRHE,setting new benchmarks for current density and stability in FeOOH-based BVO photoanodes.This work provides an effective avenue to optimize OER cocatalysts for constructing highly efficient and stable photoelectrochemical water splitting devices.
基金supportted by the Natural Science Foundations of China(No.21203025,No.11004032 and No.11074039)
文摘Nano-crystalline FeOOH particles （5-10 nm） have been uniformly mixed with electric matrix of single-walled carbon nanotubes （SWNTs） for forming FeOOH/SWNT composite via a facile ultrasonication method. Directly using the FeOOH/SWNT composite （containing 15 wt% SWNTs） as anode material for lithium battery enhances kinetics of the Li＋ insertion/extraction processes, thereby effectively improving re- versible capacity and cycle performance, which delivers a high reversible capacity of 758 mAh.g-1 under a current density of 400 mA.g-1 even after 180 cycles, being comparable with previous reports in terms of electrochemical performance for FeOOH anode. The good electrochemical performance should be ascribed to the small particle size and nano-crystalline of FeOOH, as well as the good electronic conductivity of SWNT matrix.
基金financially supported by National Natural Science Foundation of China(Nos.52407242,52162025)Specific Research Fund of the Innovation Platform for Academicians of Hainan Province(No.YSPTZX202123).
文摘Aqueous rechargeable Ni-Fe batteries exhibit unique advantages in large-scale energy storage thanks to their affordability,safety,and reliability.However,their limited energy density and Coulombic efficiency stem from unfavorable OH^(−)adsorption capability and low electrochemical activity of Fe sites,result in electrode kinetic delays for Fe anodes.Here,we report Mn and S co-modified FeOOH(MSFF)nanosheets as an advanced anode in Ni-Fe batteries,synthesized from a facile one-step surface-redox-etching method at room temperature.Based on the strong electronic coupling effect between Mn and S atoms,such MSFF anode presents fast electron transport capability,enhanced OH^(−)-adsorption capability,and redox reactivity.Specifically,the MSFF anode can achieve a high areal capacity of 2 mAh cm^(−2)at 10 mA cm^(−2),which retains a staggering 96%of the initial capacity after undergoing 9000 cycles at a higher current density of 30 mA cm^(−2).In addition,the assembled Ni-Fe battery can provide a capacity of 0.85 mAh cm^(−2)at 16 mA cm^(−2),significantly outperforming most recently reported aqueous rechargeable batteries.This work may offer an innovative and feasible approach for modulating the local electronic structure of high-performance Ni-Fe battery electrode materials.
