标题：Enhancing the Efficiency of Water Oxidation by Boron-Doped BiVO4 under Visible Light: Hole Trapping by BO4 Tetrahedra
作者：Li, Yanqing; Jing, Tao; Liu, Yuanyuan; Huang, Baibiao; Dai, Ying; Zhang, Xiaoyang; Qin, Xiaoyan; Whangbo, Myung-Hwan
作者机构：[Li, Yanqing; Liu, Yuanyuan; Huang, Baibiao; Qin, Xiaoyan] Shandong Univ, State Key Lab Crystal Mat, Jinan 250100, Peoples R China.; [Jing, Tao; Dai 更多
通讯作者地址：[Liu, YY]Shandong Univ, State Key Lab Crystal Mat, Jinan 250100, Peoples R China.
关键词：boron; doping; oxidation; photochemistry; vanadium
摘要：Boron-doped monoclinic and tetragonal phases of BiVO4 were prepared by using the urea precipitation method, and the visible-light photocatalytic activities of pristine and boron-doped BiVO4 for oxygen generation from water were compared. Boron doping enhances the photocatalytic activities of BiVO4. The reasons for this enhancement were probed by performing X-ray photoelectron, Raman, and electrochemical impedance spectroscopy measurements, and also by performing density functional calculations for model boron-doped BiVO4 structures. The photocatalytic activities of BiVO4 is enhanced by boron doping because the resulting BO4 tetrahedra, which are smaller than the VO4 tetrahedra, create an occupied defect level per boron lying approximately 0.17eV above the valence-band maximum of pristine BiVO4, and this defect level is localized because it is made up of the O 2p levels of the BO4 tetrahedron. Thus, the BO4 tetrahedra that result from boron doping act as hole traps, thereby slowing down the recombination of photogenerated electrons and holes.