ZnO supported on Cu2O{100} enhances charge transfer in dimethyldichlorosilane synthesis

摘要

In this work, three types of ZnO/Cu2O heterostructures were synthesized by depositing ZnO nanoparticles on the supports of Cu2O cubes, Cu2O octahedrons and Cu2O dodecahedrons with different exposed facets. These catalysts were used for the Rochow reaction, which is an important industrial process for the synthesis of organosilicon polymers. It was demonstrated that Cu2O cubes-supported ZnO catalyst is the most active toward dimethyldichlorosilane formation, while Cu2O dodecahedrons-supported ZnO catalyst is the least active. Both experimental results and density functional theory calculations show that, in the three cases, the charge transfer efficiency between the ZnO nanoparticle and the Cu2O{1 0 0} plane is the highest, which enhances the dissociative adsorption of methylchloride at Cu2O{1 0 0}, the subsequent reduction of Cu+ into Cu-0 and the final formation of the Cu3Si active phases. This work reveals essential information about how the Rochow reaction proceeds on the ZnO/Cu2O catalyst and demonstrates a practical strategy to rationally design highly efficient catalytic system in heterogeneous catalysis. (C) 2019 Elsevier Inc. All rights reserved.