Facile fabrication and application of SnO2-ZnO nanocomposites: insight into chain-like frameworks, heterojunctions and quantum dots

Versatile strategies for the heterostructure and related performance of nanocomposites are of fundamental importance in the development of advanced functional materials. Semiconductor oxide materials, such as SnO2 and ZnO, have attracted great interest owing to their potential to combine desirable properties. In this work, a novel SnO2-ZnO heterostructured nanocomposite has been fabricated by a sol-gel method and supercritical fluid drying processes. Nanostructure analysis indicated that the SnO2-ZnO composites show chain-like frameworks with heterojunction features, which were embedded with SnO2 and ZnO quantum dots (QDs). The size distribution of SnO2 and ZnO QDs ranged from 3 to 7 nm, which were uniformly dispersed on SnO2-ZnO chain-like frameworks. The experimental results indicated that the calcination temperature could effectively affect the photocatalytic degradation of SnO2-ZnO nanocomposites. When the calcination temperature increased from 500 to 700 degrees C, the photocatalytic degradation rate increased as the reaction time increased from 30 to 150 min. The new insight obtained in this study will be beneficial for the practical applications of binary oxide semiconductor composites for the photocatalytic degradation of organic pollutants.