采用化学共沉淀法制备了磁性壳聚糖, 然后以制得磁性壳聚糖纳米粒子为基体, 利用层层自组装原理, 在磁性壳聚糖表面原位生长ZnS∶Fe纳米晶, 制备得到磁性壳聚糖/ZnS∶Fe复合纳米粒子。采用XRD和VSM对其进行表征, 结果表明, 制备得到的磁性壳聚糖/ZnS∶Fe复合纳米粒子具有超顺磁性能, 室温下饱和磁化强度为15.88 A·m2·kg-1。以孔雀石绿为模型污染物, 采用UV-Vis手段研究磁性壳聚糖/ZnS∶Fe复合纳米粒子的光催化降解性能。 实验结果表明, 向初始浓度为10 mg/L孔雀石绿溶液中加入100 mg/L磁性壳聚糖/ZnS∶Fe复合纳米粒子, 60 min时孔雀石绿的去除率为95.3%, 重复使用5次后, 降解率略有降低(从95.3%降低到80.8%), 其反应过程符合假一级动力学的假设。因此, 磁性壳聚糖/ZnS∶Fe复合纳米粒子可以光催化降解孔雀石绿。

Magnetic chitosan/ZnS∶Fe(M-CS/ZnS∶Fe) nanocomposite was prepared and applied to the photodegradation of malachite green(MG). The synthesized M-CS/ZnS∶Fe exhibits excellent superparamagnetism and photocatalytic activity. In photodegradation studies, the effect of main experimental parameters on the decolorization efficiency was studied and optimized. The maximum decolorization efficiency of 95.3% was obtained when the initial MG concentration, M-CS/ZnS∶Fe dosage, and contact time were optimally set as 10 mg/L, 100 mg/L, and 60 min, respectively. The process kinetics can be successfully fitted to the first order kinetics of Langmuir-Hinshelwood model. Moreover, M-CS/ZnS∶Fe could be easily separated under an external magnetic field. After five consecutive runs, a small and gradual decrease from 95.3% to 80.8% in the decolorization ration was observed.