Preparation and characterization of SnO2−x/GO composite photocatalyst and its visible light photocatalytic activity for self-cleaning cotton fabrics

Abstract

Sn2+ self-doped SnO2 (SnO2−x) nanocrystal and SnO2−x/graphene oxide (SnO2−x/GO) composite photocatalyst were prepared by hydrothermal method and characterized by transmission electron microscope, energy dispersive X-ray, X-ray diffraction, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy, photocurrent and photocatalytic activity. SnO2−x/GO was hydroxylated with 3,4-dihydroxy phenyl acetic acid to obtain the carboxylated SnO2−x/GO. Cotton fabrics were cationically modified by 3-chloro-2 hydroxy propyltrim ethylammonium chloride and then finished with the carboxylated SnO2−x/GO composite photocatalyst. Cotton fabrics were characterized by SEM, XPS and self-cleaning activity. Photocatalytic activity of SnO2−x/GO composite photocatalyst and self-cleaning activity of cotton fabrics were evaluated by photocatalytic degradation of methyl orange solution and methylene blue solution under the visible light, respectively. Photocatalytic activity of SnO2−x/GO composite photocatalyst firstly increased and then decreased with the increasing molar ratio of Sn4+/Sn, and the GO concentration in SnO2−x/GO. The optimal molar ratio of Sn4+/Sn and GO concentration were 1:4 and 5%, respectively. The SnO2−x/GO finished cotton fabrics exhibited highly efficient and durable self-cleaning activity. In addition, the mechanism for SnO2−x/GO photocatalytic activity, and the mechanism and possible reactions for the chemically binding of SnO2−x/GO composite photocatalyst with cotton fabrics were proposed.