聚乙烯亚胺修饰坡缕石/CaIn2S4复合材料光催化降解甲基橙

Photocatalytic degradation of methyl orange by polyethyleneimine modified palygorskite/CaIn2S4 composites

摘要:

以聚乙烯亚胺（PEI）修饰的坡缕石（PGS(PEI)）、CaIn2S4前驱体为原料，一锅水热法制备了PEI修饰坡缕石/CaIn2S4复合材料（PGS(PEI)/CaIn2S4），通过XRD、SEM、N2吸附-脱附、UV-Vis DRS及PL表征了复合材料的物化性能，阐述了该复合材料的生长机制，测试了该复合材料光催化降解多种染料的可行性。PGS(PEI)镶嵌在纳米花状的CaIn2S4内部，修饰坡缕石质量分数 为60%的PGS(PEI)/CaIn2S4复合材料的比表面积、孔容、孔径分别为138.6 m2/g、0.49 cm3/g、14.20 nm。PGS(PEI)与CaIn2S4之间的内置电场及PEI对光生电子的迁移提高了PGS(PEI)/CaIn2S4光生载流子的分离率，可见光照射下对甲基橙的光催化降解活性高于CaIn2S4，光照60 min，对甲基橙的降解率为96.9%，?O2-为光降解反应中的主要活性基团。

Abstract:

Abstract:PGS(PEI)/CaIn2S4 composites was prepared by a one-pot hydrothermal method using polyethyleneimine (PEI) modified palygorskite (PGS(PEI)) and CaIn2S4 precursor as raw materials. The physicochemical properties of PGS(PEI)/CaIn2S4 composites were characterized by means of XRD, SEM, N2 adsorption-desorption, UV-Vis DRS and PL. The growth mechanism of the composite was described and the feasibility of photocatalytic degradation of various dyes was tested. PGS(PEI) is embedded in flower-like nano-CaIn2S4.The maximum specific surface area, pore volume and pore diameter of PGS(PEI)/CaIn2S4 (modified PGS mass ratio of 60%) are 138.6 m2/g, 0.49 cm3/g and 14.20 nm, respectively. The photogenerated carrier separation rate of composite increases attributing to the built-in electric field between PGS(PEI) and CaIn2S4 and the photoelectron transformation by PEI. Thephotocatalytic activity of 60% PGS(PEI)/CaIn2S4 for methylic orange (MO) degradation is higher than CaIn2S4 under the visible light. The degradation rate of MO is 96.9% for 60 min. The superoxide free radicals (.O2-) play an important role in the photodegradation process.