Yan Yunhui, Ni Tianjun, Du Jinge, Li Li, Fu Shuai, Li Kun, Zhou Jianguo
Key Laboratory of Medical Molecular Probes, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, China.
Dalton Trans. 2018 May 1;47(17):6089-6101. doi: 10.1039/c8dt00408k.
A novel BiVO4/BiPO4 composite with a balsam pear-shaped morphology was fabricated by a green hydrothermal synthesis approach, which didn't employ a strong acid and base, and neither a template or surfactant. The co-precipitation hydrothermal process had significant influence not only on particle size and shape, but also on the BiVO4 oriented growth along the (040) facet. The morphology, microstructure, light absorption and emission properties were analyzed by several characterization techniques. A formation mechanism for the hollow BiVO4/BiPO4 composite was proposed on the basis of time-dependent SEM observations. Charge transfer absorption and an efficient charge separation were observed by UV-vis DRS, PL spectra and photocurrent measurements, which suggest that there are chemical interactions between BiVO4 and BiPO4. The above synergistic effects of the as-prepared composite result in a higher photocatalytic performance for the degradation of RhB and MNZ compared with the single component and their physical mixture. Besides that, the special hollow structure and preferred exposure of the BiVO4 (040) facet could contribute to the dramatically improved performance. Subsequently, a possible photocatalytic mechanism over the BiVO4/BiPO4 composite was proposed based on experiment and theoretical analysis. These results indicate that the hollow BiVO4/BiPO4 composite has a great potential application value for the treatment of organic dyes and medicine wastewater.
通过绿色水热合成法制备了一种具有苦瓜形状形貌的新型BiVO4/BiPO4复合材料，该方法不使用强酸强碱，也不使用模板或表面活性剂。共沉淀水热过程不仅对粒径和形状有显著影响，而且对BiVO4沿(040)晶面的取向生长也有显著影响。采用多种表征技术对其形貌、微观结构、光吸收和发射性能进行了分析。基于时间依赖的扫描电镜观察结果，提出了中空BiVO4/BiPO4复合材料的形成机理。通过紫外可见漫反射光谱、光致发光光谱和光电流测量观察到电荷转移吸收和有效的电荷分离，这表明BiVO4和BiPO4之间存在化学相互作用。与单一组分及其物理混合物相比，所制备的复合材料的上述协同效应导致其对RhB和MNZ的降解具有更高的光催化性能。除此之外，特殊的中空结构和BiVO4(040)晶面的优先暴露有助于显著提高性能。随后，基于实验和理论分析，提出了BiVO4/BiPO4复合材料可能的光催化机理。这些结果表明，中空BiVO4/BiPO4复合材料在处理有机染料和医药废水方面具有巨大的潜在应用价值。
