Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan 528000, China.
School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming 525000, China.
Int J Environ Res Public Health. 2023 Feb 10;20(4):3093. doi: 10.3390/ijerph20043093.
Emerging contaminants, which mainly exist as organic pollutants and pose adverse biological effects, could be removed using photocatalytic degradation, resulting in a low-cost and environmentally friendly solution. Herein, BiVO nanoparticles with different morphologies and photocatalytic performances were synthesized by hydrothermal treatment at different residence times. The XRD and SEM results indicate that the crystal phase of BiVO gradually transformed from a single tetragonal phase to a single monoclinic crystal phase as the hydrothermal time increased, and with the extension of the hydrothermal time, the morphology of BiVO nanoparticles gradually differentiated from a smooth spherical shape to flower-like shapes composed of polyhedrons; the size of the crystals also increased accordingly. Methylene blue (MB), used as a probe of organic pollutants, was degraded under visible light irradiation by all BiVO samples to investigate its photocatalytic activities. The experimental results show that the longer the hydrothermal time, the better the photocatalytic performance. The optimum hydrothermal time was 24 h, at which the sample showed the highest photocatalytic activity for MB degradation. This work shows a convenient strategy for control of the crystal phase of BiVO-based photocatalysts based on the understanding of the crystal morphology evolution mechanism, which will benefit the researchers in designing new BiVO-based photocatalysts with high efficiency for emerging contaminants' degradation.
新兴污染物主要以有机污染物的形式存在，并具有不良的生物效应，可采用光催化降解去除，从而提供一种低成本且环保的解决方案。在此，通过在不同停留时间下进行水热处理，合成了具有不同形貌和光催化性能的 BiVO 纳米粒子。XRD 和 SEM 结果表明，随着水热时间的增加，BiVO 的晶体相逐渐从单一四方相转变为单一单斜相，并且随着水热时间的延长，BiVO 纳米粒子的形貌逐渐从光滑的球形分化为多面体组成的花状；晶体的尺寸也相应增大。亚甲基蓝 (MB) 作为有机污染物的探针，在可见光照射下通过所有 BiVO 样品降解，以研究其光催化活性。实验结果表明，水热时间越长，光催化性能越好。最佳水热时间为 24 h，在此时间下，样品对 MB 降解表现出最高的光催化活性。这项工作展示了一种基于对晶体形貌演化机制的理解来控制基于 BiVO 的光催化剂晶体相的便捷策略，这将有助于研究人员设计用于降解新兴污染物的高效新型基于 BiVO 的光催化剂。
