Synthesis, Electronic Structure and Visible Light Photocatalytic Performance of Quaternary BiMnVO₅

Abstract

Removal of organic pollutants from water bodies by photocatalysis has broad application prospects in the field of sewage purification. In this study, the quaternary BiMnVO 5 was synthesized by hydrothermal method and solid-state reaction, respectively. The morphology, structure and optical properties of the catalysts were characterized, and the electronic structure was calculated. Results showed that the hydrothermal method can rapidly synthesize pure BiMnVO 5 with high crystallinity. BiMnVO 5 is a semiconductor with a direct band gap of 1.8 eV, which is consistent with the results of first-principles calculations. Analysis of the density of states further reveals that the optical absorption band are attributed to the transitions from Mn3d/O2p to V3d. The photocatalytic results show that the BiMnVO 5 synthesized by hydrothermal method exhibits the highest catalytic activity. About 98% Methylene Blue (MB) is degraded when exposed to visible light for 4 h. The hydroxyl radicals and photo-generated holes are proved to be the main active substances in the photocatalytic process. After 5 cycles, it still maintains capacity of degrading 85% MB in 4 h under visible light irradiation, while its morphology and structure remain unchanged, which indicates BiMnVO 5 a good photocatalyst with reliable stability.

Magnetic CoFe1.95Y0.05O4-Decorated Ag3PO4 as Superior and Recyclable Photocatalyst for Dye Degradation

“…An overabundance of CoFe 1.95 Y 0.05 O 4 may actually decrease the degradation rate because they may cover the Ag 3 PO 4 surface and block light, ultimately leading to lower degradation efficiency. The photocatalytic degradation efficiency of the composite materials is competitive to other reported photocatalysts ( Table 1 ) [ 24 , 25 , 26 , 27 , 28 , 29 , 30 ].…”

Magnetic Ag2S/Ag/CoFe1.95Sm0.05O4 Z-scheme Heterojunction: Preparation and Its Photocatalytic Degradation Property

“…This research provides a useful approach to develop photocatalysts with high efficiency, narrow band gap and magnetism. Key words: Ag 2 S/Ag/CoFe 1.95 Sm 0.05 O 4 ; Z-scheme heterojunction; photocatalytic degradation; recycling 化学染料废水排放到环境中会污染生活环境, 破坏生态平衡, 因此开发高效的废水处理技术和具 有高催化活性且易回收的光催化剂极为迫切, 其中 半导体光催化氧化是最有前途的光催化技术 [1][2][3] 。 MFe 2 O 4 是一种典型的窄带隙、 无毒和有磁性的 光催化材料, 掺杂稀土元素可以提高 MFe 2 O 4 饱和 磁化强度并拓宽其可见光响应的范围 [4][5] 。Ag 3 PO 4 [6] 和 Ag 2 S [7][8] 等催化剂具有很高的光催化活性, 尤其 当 Ag 2 S 与 Ag 耦合, Ag 表面等离子体共振及其形成 的异质结协同效应又能解决光腐蚀问题 [9][10] 。尽管 如此, 单一的 CoRE x Fe 1-x O 4 或 Ag 2 S/Ag 的光催化活 性仍然有待提高, 光生载流子易发生复合、成本高 且难回收等问题又限制了其应用。因此, 研究者一 般通过负载改性来提高催化剂的催化活性, 铁氧体…”