ABSTRACT

Protonated g-C₃N₄/MoS₂ heterojunction with enhanced photocatalytic activity was prepared by treating g-C₃N₄/MoS₂ with formic acid and using a hydrothermal method. The microstructure and morphology of the heterojunctions were analysed by XRD, FTIR, SEM, TEM, and XPS technology, respectively. The photodegradation experiment results verified that the formic acid treatment has a positive effect on the photocatalytic performance of g-C₃N₄/MoS₂ heterojunctions. The as-prepared protonated g-C₃N₄/MoS₂ composite with 5 wt% of MoS₂ exhibited the highest photodegradation rate and photodegradation kinetic constant (k) for degradation of methyl orange (MO) dye. The activated species trapping experiment revealed that the superoxide radical (·O₂⁻) plays an important role for degradation of MO dye. Furthermore, the investigation on the photocatalytic mechanism inferred that the enhanced photocatalytic property of protonated g-C₃N₄/MoS₂ composite could be attributed to the Z-scheme electron migration mechanism in composite and the improved photo-induced electron-hole separation.

摘要

 通过用甲酸和水热法处理gC ₃ N ₄ /MoS ₂制备了具有增强光催化活性的质子化gC ₃ N ₄ /MoS ₂异质结。分别通过XRD、FTIR、SEM、TEM和XPS技术分析了异质结的微观结构和形貌。光降解实验结果证实甲酸处理对gC ₃ N ₄ /MoS ₂异质结的光催化性能有积极影响。所制备的质子化 gC ₃ N ₄ /MoS ₂复合材料，含 5 wt% MoS₂表现出最高的光降解速率和光降解​​动力学常数 ( k ) 降解甲基橙 (MO) 染料。活化物种捕获实验表明超氧自由基（·O ₂ ^-）对MO 染料的降解起重要作用。此外，对光催化机理的研究推断，质子化 gC ₃ N ₄ /MoS ₂复合材料的光催化性能增强可归因于复合材料中的 Z 型电子迁移机制和改进的光致电子空穴分离。