Hydrophilic macroporous SnO2/rGO composite prepared by melamine template for high efficient photocatalyst

Abstract

Based on the electrostatic interaction between melamine and graphene oxide (GO), and the solubility of melamine in hot water, we adopt melamine as template and prepare hydrophilic macroporous SnO2/reduced graphene oxide (SnO2/rGO-HM) composite for high efficient photocatalyst. During the preparation process, SnO2 nanoparticles are synthesized on GO sheets by hydrolysis of SnCl4·5H2O, and then melamine particles are added to form clad structure with melamine as cores and SnO2/GO as cladding layers. During subsequent heat annealing, melamine cores protect the oxygen-containing groups on the inner layer of SnO2/GO sheet, which ensures the hydrophilicity of SnO2/rGO composite. Meanwhile, melamine templates are removed by rinsing in hot water to produce macroporous structure. As a template agent, the effect of melamine dosage on the pore structure and photocatalysis performance is discussed. Moreover, the relationship between SnCl4·5H2O dosage and photocatalytic activity of SnO2/rGO-HM composite is also clarified. When used for degradation of Rhodamine B and methylene blue, SnO2/rGO-HM photocatalyst shows a better photocatalytic activity than that of ordinary SnO2/rGO, pure SnO2, and commercial TiO2 photocatalyst (P25). The excellent photodegradation performance is attributed to the hydrophilicity, high specific surface area of composite, and the uniform distribution of SnO2 nanoparticles on rGO sheets.