College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China.
Environ Sci Pollut Res Int. 2022 Oct;29(48):73282-73291. doi: 10.1007/s11356-022-20550-1. Epub 2022 May 27.
CdS-based composites as the highly efficient photocatalyst have been extensively investigated in recent years due to the suitable band gap and high photocatalytic efficiency. In this study, the effect of various factors (pH, U(VI) concentration, contents, and types of photocatalyst) on photocatalytic reduction of U(VI) by MoS/CdS composite was investigated. The optimized experimental conditions (e.g., pH 7.0, 20 mg/g U(VI), and 1.0 g/L photocatalyst) was obtained by batch techniques. Approximately 97.5% of U(VI) was photo-catalytically reduced into U(IV) by 2.5 wt% MoS/CdS composite within 15 min. After 5 cycles, 2.5 wt% MoS/CdS composite still exhibited the high removal efficiency of U(VI) under 50-min irradiation, indicating the good stability. The photo-reduction mechanism of U(VI) on MoS/CdS composite was attributed to the O radicals by quenching experiments, ESR, and XPS analysis. The findings indicate that CdS-based catalyst has a great potential for the photocatalytic reduction of uranyl in actual environmental remediation.
基于 CdS 的复合材料作为一种高效的光催化剂，由于其合适的带隙和高光催化效率，近年来受到了广泛的研究。在本研究中，考察了各种因素（pH、U(VI)浓度、含量和光催化剂类型）对 MoS/CdS 复合材料光催化还原 U(VI)的影响。通过批处理技术获得了优化的实验条件（例如，pH 为 7.0、U(VI)浓度为 20 mg/g 和光催化剂用量为 1.0 g/L）。在 15 分钟内，2.5wt% MoS/CdS 复合材料将 97.5%的 U(VI)光催化还原为 U(IV)。经过 5 次循环，在 50 分钟的辐照下，2.5wt% MoS/CdS 复合材料仍表现出高的 U(VI)去除效率，表明其稳定性良好。通过淬灭实验、ESR 和 XPS 分析，将 U(VI)在 MoS/CdS 复合材料上的光还原机理归因于 O 自由基。研究结果表明，基于 CdS 的催化剂在实际环境修复中的光催化还原铀方面具有很大的潜力。
