CdS/Zn-Fe LDO复合材料光催化降解孔雀石绿

Photocatalytic degradation of malachite green by CdS/Zn-Fe LDO composite materials

摘要:

采用沉淀法将CdS与锌铁层状双金属氢氧化物（Zn-Fe LDH）复合，高温煅烧后得到CdS/ZnO-ZnFe2O4复合材料（CdS/Zn-Fe LDO）。利用XRD、SEM、UV-vis DRS及PL对复合材料的结构、形貌、光学性能进行了表征。研究了该复合材料在可见光下对孔雀石绿的光降解，结果表明：CdS/Zn-Fe LDO复合材料对孔雀石绿的光催化降解能力高于CdS或Zn-Fe LDO，其中，m(CdS) : m(Zn-Fe LDH)=1 : 1配比制备的CdS/Zn-Fe LDO（1:1）光催化活性最大。光照20 min，20 mg CdS/Zn-Fe LDO（1:1）对20 mg/L孔雀石绿的光降解率为96.6%。此外，该复合材料还可降解罗丹明B、亚甲基蓝、甲基橙、结晶紫等染料且光降解反应符合一级反应动力学。

Abstract:

The CdS/ZnO-ZnFe2O4 composites (CdS/Zn-Fe LDO) were prepared by high-temperature roasting with complex using the method of precipitation CdS and zinc iron layered double hydroxides (Zn-Fe LDH).The structure, morphology and optical properties of the composite were characterized by XRD, SEM, UV-Vis DRS and PL. The photodegradation of malachite green by CdS/Zn-Fe LDO was studied under visible light. The experimental results showed that the photocatalytic degradation capacity of CdS/Zn-Fe LDO composites were higher than CdS or Zn-Fe LDO. The photocatalytic activity of m(CdS) : m(Zn-Fe LDH)=1 : 1 (CdS/Zn-Fe LDO（1:1）) was the biggest among composites. The degradation rate of malachite green was 96.6% under the optimal conditions of 20 min, initial concentration 20 mg/L, CdS/Zn-Fe LDO (1:1) dosage of 20 mg as well as visible light. Furthermore, the composites also degraded other dyes such as, rhodamine b, methylene blue, methyl orange and crystal violet. The kinetics of photodegradation reactions were followed with pseudo first order kinetic.