Unraveling oxygen vacancy changes of WO3 photoanodes for promoting oxygen evolution reaction
Unraveling oxygen vacancy changes of WO3 photoanodes for promoting oxygen evolution reaction
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DOI：
10.1016/j.apcatb.2023.123682
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发表时间：
2024-01
期刊：
影响因子：
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通讯作者：
Lianglin Yan;Guojun Dong;Xiaojuan Huang;Yun Zhang;Yingpu Bi
中科院分区：
文献类型：
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作者：
Lianglin Yan;Guojun Dong;Xiaojuan Huang;Yun Zhang;Yingpu Bi
半导体光阳极上的氧空位对提高光电化学水氧化性能具有重要作用。尽管如此，仍然缺乏明确的阐明有关的结构变化及其对电荷传输过程中的析氧反应（OER）的影响。在此，通过Ar等离子体雕刻在WO 3纳米片光阳极上合理地引入氧空位，导致在AM 1.5 G太阳照射下在1.23 VRHE下的光电流密度为2.76 mA cm-2，与原始WO 3光阳极相比增加了三倍。综合实验和理论计算表明，WO 3光阳极表面氧空位的自修复过程更容易通过从吸附的H2O分子中捕获氧原子来实现。然而，一些幸存的氧空位在亚表面可以有效地增加电荷载流子密度，并提供额外的驱动力，以加速界面电荷传输，导致增强的光电化学（PEC）活动。更重要的是，金属氧化物半导体上的氧空位自修复是一种普遍现象，这可能会为设计和构建用于PEC水氧化的高效光阳极带来新的见解。
Oxygen vacancy (VO) on semiconductor photoanode plays an important role in enhancing photoelectrochemical water oxidation performances. Nonetheless, there is still a lack of definitive elucidation regarding the structural changes and their impact on charge transport during the oxygen evolution reaction (OER). Herein, oxygen vacancies were rationally introduced on WO3nanoflake photoanodes via Ar-plasma engraving, resulting in a threefold increase in the photocurrent density of 2.76 mA cm−2at 1.23 VRHEunder AM 1.5 G solar irradiation compared to the pristine WO3photoanode. Comprehensive experiments and theoretical calculations reveal that the self-healing process of surface oxygen vacancies on WO3photoanodes should be more easily achieved by capturing oxygen atoms from adsorbed H2O molecules. However, some survived oxygen vacancies in the subsurface could effectively increase the charge carrier density and provide the additional driving force to accelerate the interfacial charge transport, leading to enhanced photoelectrochemical (PEC) activities. More importantly, the oxygen vacancy self-healing on metal-oxide semiconductors is a universal phenomenon, which might bring new insights for design and construction of highly efficient photoanodes for PEC water oxidation.