Abstract

Due to the unique layered structures and narrow bandgap, bismuth oxyiodide has become a new photocatalyst with high efficacy. Herein, a series of bismuth oxyiodide with different atomic ratio of Bi:I have been successfully synthesized via hydrothermal methods through simply changing the ratio of Bi and I raw materials, and the composition, optical property, and photocatalytic performance behaviors were investigated. X-ray diffraction patterns, scanning electron microscope images, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy spectra, and ultraviolet–visible spectra analysis confirmed the as-prepared bismuth oxyiodides were Bi₇O₉I₃, Bi₃O₅I₂, and BiOI microspheres with different sizes and bandgaps, which decreased with increased ratios of Bi:I. Due to the larger specific surface areas and the narrower bandgap, Bi₇O₉I₃ can produce more superoxide under simulated sunlight irradiation than Bi₃O₅I₂ and BiOI microspheres. Photocatalytic dye degradation test showed that Bi₇O₉I₃ presented the best photocatalytic performance, followed by Bi₃O₅I₂ and BiOI.

摘要

由于独特的层状结构和窄带隙，碘氧化铋已成为一种新型的高效光催化剂。在此，通过简单改变Bi和I原料的比例，通过水热法成功合成了一系列具有不同Bi:I原子比的碘化铋，并对其组成、光学性质和光催化性能进行了研究。X 射线衍射图、扫描电子显微镜图像、能量色散 X 射线光谱、X 射线光电子能谱和紫外-可见光谱分析证实所制备的碘化铋为 Bi ₇ O ₉ I ₃、Bi ₃ O ₅我₂和具有不同尺寸和带隙的 BiOI 微球，随着 Bi:I 比率的增加而减小。由于较大的比表面积和较窄的带隙，Bi ₇ O ₉ I ₃在模拟阳光照射下可以比Bi ₃ O ₅ I ₂和BiOI 微球产生更多的超氧化物。光催化染料降解试验表明，Bi ₇ O ₉ I ₃表现出最好的光催化性能，其次是Bi ₃ O ₅ I ₂和BiOI。