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
目前,水环境中的抗生素污染已引发一系列严峻的环境问题。异相电芬顿(Heterogeneous Electro-Fenton,HEF)技术因能减少铁污泥形成、提高催化剂稳定性并拓宽pH适用范围,在抗生素废水处理领域展现出巨大的应用潜力。常用的铁基材料存在Fe^...目前,水环境中的抗生素污染已引发一系列严峻的环境问题。异相电芬顿(Heterogeneous Electro-Fenton,HEF)技术因能减少铁污泥形成、提高催化剂稳定性并拓宽pH适用范围,在抗生素废水处理领域展现出巨大的应用潜力。常用的铁基材料存在Fe^(3+)/Fe^(2+)循环速率慢、后负载材料易脱离等问题,制约了其实际应用。为此,通过溶剂热法原位制备了不同Fe/Co摩尔比的层状Fe_(m)/Co_(n)-MOFs@CF材料,并在低温(100~200℃)条件下进行活化,将其作为HEF降解污染物体系的催化剂,用于四环素(Tetracycline,TC)的降解。结果表明:所制备的双金属催化剂对TC的降解效果优于单金属有机框架(Metal-Organic Frameworks,MOFs)材料,通过优化Fe/Co摩尔比、煅烧温度及反应条件,发现在电压为-0.8 V vs Ag/AgCl、自然pH、过氧化氢(H_(2)O_(2))添加量为60μL的条件下,经200℃活化的Fe_(2)/Co_(1)-MOFs@CF(记为Fe_(2)/Co_(1)-MOFs-200@CF)可在60 min内去除约96%的TC。此外,在pH值为3~11时,该催化剂对TC均表现出良好的去除效果,拓宽了HEF降解污染物体系的pH适用范围;在实际水体的处理中也表现出优异的降解性能,并在5轮循环测试后仍保持良好的可重复使用性和稳定性。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.
文摘目前,水环境中的抗生素污染已引发一系列严峻的环境问题。异相电芬顿(Heterogeneous Electro-Fenton,HEF)技术因能减少铁污泥形成、提高催化剂稳定性并拓宽pH适用范围,在抗生素废水处理领域展现出巨大的应用潜力。常用的铁基材料存在Fe^(3+)/Fe^(2+)循环速率慢、后负载材料易脱离等问题,制约了其实际应用。为此,通过溶剂热法原位制备了不同Fe/Co摩尔比的层状Fe_(m)/Co_(n)-MOFs@CF材料,并在低温(100~200℃)条件下进行活化,将其作为HEF降解污染物体系的催化剂,用于四环素(Tetracycline,TC)的降解。结果表明:所制备的双金属催化剂对TC的降解效果优于单金属有机框架(Metal-Organic Frameworks,MOFs)材料,通过优化Fe/Co摩尔比、煅烧温度及反应条件,发现在电压为-0.8 V vs Ag/AgCl、自然pH、过氧化氢(H_(2)O_(2))添加量为60μL的条件下,经200℃活化的Fe_(2)/Co_(1)-MOFs@CF(记为Fe_(2)/Co_(1)-MOFs-200@CF)可在60 min内去除约96%的TC。此外,在pH值为3~11时,该催化剂对TC均表现出良好的去除效果,拓宽了HEF降解污染物体系的pH适用范围;在实际水体的处理中也表现出优异的降解性能,并在5轮循环测试后仍保持良好的可重复使用性和稳定性。
