Effect of BiVO4 Crystalline Phases on the Photoinduced Carriers Behavior and Photocatalytic Activity
Effect of BiVO4 Crystalline Phases on the Photoinduced Carriers Behavior and Photocatalytic Activity
复制标题
BiVO4晶相对光生载流子行为和光催化活性的影响
DOI：
10.1021/jp206798d
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发表时间：
2012-01-26
影响因子：
3.7
通讯作者：
Xie, Tengfeng
中科院分区：
文献类型：
--
作者：
Fan, Haimei;Jiang, Tengfei;Xie, Tengfeng
采用共沉淀法和熔盐法制备了一系列不同晶相的BiVO 4光催化剂（四方晶相、单斜晶相和单斜/四方晶相）。高分辨透射电子显微镜（HRTEM）结果表明，纳米颗粒表面形成了紧密接触的单斜/四斜异质相界面，单斜相主要分布在纳米颗粒表面。表面光电压（SPV）和瞬态光电压（TPV）技术被用来进一步研究光生载流子的转移过程。结果表明，BiVO 4样品的晶相对光生电荷行为有显著的影响，单斜/四斜异质相界面的存在为电荷转移提供了空间条件，促进了光生电子-空穴对的分离，改变了光生载流子的迁移方向.详细讨论了光生载流子的行为与光催化活性的关系，为深入了解光催化活性增强的内在原因提供了理论依据。
A series of different crystalline phases BiVO4 photocatalysts (tetragonal, monoclinic, and monoclinic/tetragonal heterophase) have been prepared by a coprecipitation and molten salt method. High-resolution transmission electron microscopy (HRTEM) results show that an interface of intimate contact is formed in monoclinic/tetragonal heterophase and monoclinic phase is mainly on the surface of nanoparticles. Surface photovoltage (SPV) and transient photovoltage (TPV) techniques are used to further investigate the transfer process of photoinduced charge carriers. The results show that the behavior of photoinduced charges markedly depend on the crystalline phases of BiVO4 samples, and the presence of interface in monoclinic/tetragonal heterophase provides a spatial condition for charge transfer, promotes the separation of photoinduced electron-hole pairs, and changes the migration direction of photoinduced carriers. The relationship between behavior of photoinduced charge carriers and photocatalytic activity was discussed in detail, which would provide a greater insight into the intrinsic reasons of the enhancement in photocatalytic activity.