Rapid Synthesis of SnO/Sn Composites Via a Simplified Solid-State Reaction Method for Enhanced Photocatalytic Activity

This article adopts a simple solid-phase reaction method to rapidly synthesis efficient SnO/Sn composite photocatalysts using SnCl2·2H2O and NaOH powders as raw materials. The structural characteristics of the synthesized catalysts were systematically studied using analysis techniques such as X-ray diffraction, X-ray photoelectron spectroscopy, and diffuse reflectance spectroscopy. The research results show that SnCl2·2H2O and NaOH can quickly react and generate SnO/Sn composites by being placed in a centrifuge tube and shaken by a vortex mixer. NaOH has a strong reducing ability towards divalent tin, and as the content of NaOH increased, the proportion of Sn in the corresponding products significantly increased. Scanning electron microscopy and transmission electron microscopy images reveal that the sample was composed of aggregates formed by the focusing of a large number of nanocrystals. The X-ray photoelectron spectroscopy characterization confirmed the presence of oxygen vacancy defects in the sample. The diffuse reflectance spectroscopy analysis shows that compared to SnO reagents, the synthesized samples had strong absorption ability in both ultraviolet and visible light regions. The photocatalytic experiment proved that the prepared catalysts exhibit excellent photocatalytic degradation ability. Under simulated sunlight irradiation, the sample with lower NaOH in the raw material can completely degrade methyl orange within 9 min. Finally, a reaction mechanism for photocatalytic degradation of methyl orange was proposed.