Zhu Hong-Qing, Yang Bing, Wei Shi-Qiang, Yang Jing-Jing, Zhang Jin-Zhong
College of Resources and Environment, Southwest University, Chongqing 400715, China.
Environment and Quality Test Department, Chongqing Chemical Industry Vocational College, Chongqing 401228, China.
Huan Jing Ke Xue. 2020 Feb 8;41(2):756-762. doi: 10.13227/j.hjkx.201908089.
To develop low consumption and an environmentally friendly degradation technology for organic pollutants, micro-SiC/graphene composite materials were synthesized by photocatalytic reduction, and the composition and morphology of the prepared materials were characterized by XRD, FTIR, Raman spectroscopy, XPS, and SEM. Rhodamine B (RhB) was selected as the simulated pollutant to investigate the photocatalytic activity and stability of composite materials under visible light irradiation. The degradation mechanism was preliminarily discussed by active species capture experiments. Results show that the lives of photogenerated electron and photogenerated hole of SiC were prolonged when combined with graphene, which improved the photocatalytic activity and stability of composite materials. The degradation efficiency of RhB reached 92.7% with the composite material of SiC/graphene ratio (1:0.8) under 60 min irradiation, and the degradation process accorded with the first-order reaction kinetic equation. The contribution of main active species for photocatalytic degradation followed with a decreasing order of photogenerated hole (h), superoxide anion radical (·O), photogenerated electron (e), and hydroxyl radical (·OH).
为开发一种低消耗且环境友好的有机污染物降解技术,通过光催化还原法合成了微SiC/石墨烯复合材料,并采用XRD、FTIR、拉曼光谱、XPS和SEM对所制备材料的组成和形貌进行了表征。选用罗丹明B(RhB)作为模拟污染物,研究复合材料在可见光照射下的光催化活性和稳定性。通过活性物种捕获实验初步探讨了降解机理。结果表明,SiC与石墨烯复合时,其光生电子和光生空穴的寿命得以延长,提高了复合材料的光催化活性和稳定性。在60 min照射下,SiC/石墨烯比例为(1:0.8)的复合材料对RhB的降解效率达到92.7%,降解过程符合一级反应动力学方程。光催化降解主要活性物种的贡献顺序为光生空穴(h)>超氧阴离子自由基(·O)>光生电子(e)>羟基自由基(·OH)。