Preparation of hierarchical dandelion-like CuO microspheres with enhanced catalytic performance for dimethyldichlorosilane synthesis

Abstract

Hierarchical dandelion-like CuO (HD–CuO) microspheres composed of nanoribbons were prepared via a facile hydrothermal method. The samples were characterized by nitrogen adsorption, X-ray diffraction, temperature-programmed reduction, thermogravimetric analysis, transmission electron microscopy and scanning electron microscopy. It was found that the reaction temperature, reaction time and reagent amounts had a significant effect on the morphology and structure of HD–CuO. The obtained HD–CuO microspheres possessed a surface area of 10.6–57.5 m² g⁻¹ and a diameter of 3–6 μm. In the formation process, ethylene glycol was adsorbed on the surface of the CuO nanoribbons and it acted as the structure-directing agent and thereafter the CuO nanoribbons were self-assembled into HD–CuO. The investigation of the Rochow reaction showed that the HD–CuO catalyst had a better catalytic performance in dimethyldichlorosilane synthesis than the commercial CuO microparticles and commercial CuO–Cu₂O–Cu catalyst, owing to its well-developed hierarchically porous structure and higher specific surface area, leading to the increased contact interface among reaction gas, solid catalyst and solid silicon, together with enhanced mass transportation.