Chung Hoi Ying, Toe Cui Ying, Chen Weijian, Wen Xiaoming, Wong Roong Jien, Amal Rose, Abdi Fatwa Firdaus, Ng Yun Hau
School of Energy and Environment, City University of Hong Kong, Kowloon, Hong Kong SAR, P. R. China.
Particles and Catalysis Research Group, School of Chemical Engineering, The University of New South Wales, NSW, 2052, Australia.
Small. 2021 Sep;17(35):e2102023. doi: 10.1002/smll.202102023. Epub 2021 Jul 28.
Bismuth tungstate (Bi WO ) thin film photoanode has exhibited an excellent photoelectrochemical (PEC) performance when the tungsten (W) concentration is increased during the fabrication. Plate-like Bi WO thin film with distinct particle sizes and surface area of different exposed facets are successfully prepared via hydrothermal reaction. The smaller particle size in conjunction with higher exposure extent of electron-dominated {010} crystal facet leads to a shorter electron transport pathway to the bulk surface, assuring a lower charge transfer resistance and thus minimal energy loss. In addition, it is proposed based on the results from conductive atomic force microscopy that higher W concentration plays a crucial role in facilitating the charge transport of the thin film. The "self-doped" of W in Bi WO will lead to the higher carrier density and improved conductivity. Thus, the variation in the W concentration during a synthesis can be served as a promising strategy for future W based photoanode design to achieve high photoactivity in water splitting application.
在制备过程中增加钨（W）的浓度时，钨酸铋（Bi₂WO₆）薄膜光阳极表现出优异的光电化学（PEC）性能。通过水热反应成功制备了具有不同粒径和不同暴露晶面表面积的片状Bi₂WO₆薄膜。较小的粒径与以电子为主的{010}晶面的更高暴露程度相结合，导致电子传输到本体表面的路径更短，确保了更低的电荷转移电阻，从而使能量损失最小化。此外，基于导电原子力显微镜的结果提出，较高的W浓度在促进薄膜的电荷传输中起着关键作用。Bi₂WO₆中W的“自掺杂”将导致更高的载流子密度和改善的导电性。因此，在合成过程中W浓度的变化可以作为未来基于W的光阳极设计的一种有前景的策略，以在水分解应用中实现高光活性。
