Zhang Xiuping, Qin Fengqiu, Zhong Yuanyuan, Xiao Tian, Yu Qiang, Zhu Xiaodong, Feng Wei, Qi Zhiyong
School of Mechanical Engineering, Chengdu University, Chengdu 610106, China.
Sichuan Province Engineering Technology Research Center of Powder Metallurgy, Chengdu 610106, China.
Molecules. 2024 Oct 17;29(20):4911. doi: 10.3390/molecules29204911.
Bismuth-based photocatalytic materials have been widely used in the field of photocatalysis in recent years due to their unique layered structure. However, single bismuth-based photocatalytic materials are greatly limited in their photocatalytic performance due to their poor response to visible light and easy recombination of photogenerated charges. At present, constructing semiconductor heterojunctions is an effective modification method that improves quantum efficiency by promoting the separation of photogenerated electrons and holes. In this study, the successful preparation of an InO/BiWO (InO/BWO) II-type semiconductor heterojunction composite material was achieved. XRD characterization was performed to conduct a phase analysis of the samples, SEM and TEM characterization for a morphology analysis of the samples, and DRS and XPS testing for optical property and elemental valence state analyses of the samples. In the II-type semiconductor junction system, photogenerated electrons () on the InO conduction band (CB) migrate to the BWO CB, while holes () on the BWO valence band (VB) transfer to the InO VB, promoting the separation of photoinduced charges, raising the quantum efficiency. When the molar ratio of InO/BWO is 2:6, the photocatalytic degradation degree of rhodamine B (RhB) is 59.4% (44.0% for BWO) after 60 min illumination, showing the best photocatalytic activity. After four cycles, the degradation degree of the sample was 54.3%, which is 91.4% of that of the first photocatalytic degradation experiment, indicating that the sample has good reusability. The XRD results of 2:6 InO/BWO before and after the cyclic experiments show that the positions and intensities of its diffraction peaks did not change significantly, indicating excellent structural stability. The active species experiment results imply that is the primary species. Additionally, this study proposes a mechanism for the separation, migration, and photocatalysis of photoinduced charges in II-type semiconductor junctions.
近年来，铋基光催化材料因其独特的层状结构而在光催化领域得到广泛应用。然而，单一的铋基光催化材料由于对可见光响应较差且光生电荷易于复合，其光催化性能受到极大限制。目前，构建半导体异质结是一种通过促进光生电子和空穴的分离来提高量子效率的有效改性方法。在本研究中，成功制备了InO/BiWO（InO/BWO）II型半导体异质结复合材料。进行XRD表征以对样品进行相分析，进行SEM和TEM表征以对样品进行形貌分析，进行DRS和XPS测试以对样品进行光学性质和元素价态分析。在II型半导体结体系中，InO导带（CB）上的光生电子（）迁移到BWO的CB，而BWO价带（VB）上的空穴（）转移到InO的VB，促进了光生电荷的分离，提高了量子效率。当InO/BWO的摩尔比为2:6时，在光照６０分钟后，罗丹明B（RhB）的光催化降解程度为59.4%（BWO为44.0%），显示出最佳的光催化活性。经过四个循环后，样品的降解程度为54.3%，是第一次光催化降解实验的91.4%，表明样品具有良好的可重复使用性。循环实验前后2:6 InO/BWO的XRD结果表明，其衍射峰的位置和强度没有明显变化，表明具有优异的结构稳定性。活性物种实验结果表明是主要物种。此外，本研究提出了II型半导体结中光生电荷的分离、迁移和光催化的机制。
