摘要
通过水热法制备了不同复合比例的AgVO_3/BiVO_4复合型光催化剂,以有机染料甲基橙作为目标降解物评价了其光催化活性,并通过X射线衍射、扫描电子显微镜、X射线能谱、X射线光电子能谱和紫外–可见漫反射光谱对其进行了表征。结果表明:制备的样品纯度很高,复合AgVO3后,BiVO_4的晶体结构未发生改变,但形貌由石笼状变为分散的粒状混合体,光吸收性能增强,同时,二者形成了异质结结构,进一步促进了光生电子-空穴的分离,从而提高了光催化活性。当AgVO_3与BiVO_4的摩尔比为70%时,光催化活性最高且稳定性良好,光照50min对甲基橙降解率高达96.7%,较纯BiVO_4提高约86.5%,且该体系中的主要活性氧物质为空穴。
AgVO3/BiVO4 composite photocatalysts were prepared by a hydrothermal method. The photocatalytic activities of the synthesized samples were evaluated by the degradation of methyl orange. And the samples were analyzed by X-ray diffraction, scanning electron microscopy, X-ray energy spectroscopy, X-ray photoelectron spectroscopy and UV-visible diffuse reflectance spectroscopy. The results exhibited that the AgVO3/BiVO4 samples were of good purity. After compounding AgVO3, the crystal structure of BiVO4 did not change, but the morphology changed from a stone cage to a single irregular stone, and had a enhanced light absorption performance. At the same time, the formation of a heterojunction structure further promoted the separation of photo electron-holes, then improving the photocatalytic activity. When the mass ratio of AgVO3/BiVO4 was 70%, the composite showed the highest photocatalytic activity, and the degradation rate of methyl orange was 96.7%, 86.5% higher than pure BiVO4. Recycling experiments presented that heterojunctions retained excellent photo-stability after five-time recycles. And the holes were the main active species in the process of photocatalytic degradation.
作者
张宇
王敏
周鑫
杨光俊
柴天昱
朱彤
ZHANG Yu;WANG Min;ZHOU Xin;YANG Guangjun;CHAI Tianyu;ZHU Tong(School of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819, China;Liaoning Wastewater Treatment and Management Center, Shenyang 110000, China)
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2019年第1期125-131,共7页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金青年项目(21207093)
辽宁省高等学校优秀人才支持计划(LJQ2014023)项目
关键词
偏钒酸银/钒酸鉍复合材料
光催化剂
异质结
可见光
甲基橙
silver vanadate/bismuth vanadate composite
photocatalysts
heterojunction
visible light
methyl orange