Diffusion-controlled synthesis of Cu-based catalysts for the Rochow reaction  

扩散控制合成Cu基催化剂及其Rochow反应性能研究（英文）

作　　者：刘合之 李晶 纪永军 张在磊 汪学广 钟子宜 苏发兵 

机构地区：[1]State Key Laboratory of Advanced Special Steel,School of Materials Science and Engineering,Shanghai University [2]State Key Laboratory of Multiphase Complex Systems,Institute of Process Engineering,Chinese Academy of Sciences [3]Institute of Chemical and Engineering Sciences,Agency for Science,Technology and Research (A~*STAR) [4]Institute of Industrial Chemistry and Energy Technology,Shenyang University of Chemical Technology

出　　处：《Science China Materials》2017年第12期1215-1226,共12页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (21506224);the Institute of Chemical and Engineering Sciences (ICES) for the kind support of the collaboration

摘　　要：The properties of materials are strongly dependent on their structures. The diffusion effect is a main kinetic factor that can be used to regulate the growth and structure of materials. In this work, we developed a systematic and feasible strategy to synthesize Cu2O solid spheres and hexahedrons by controlling the diffusion coefficients. These Cu2O products can be successively transformed into corresponding Cu hollow spheres and hexahedrons as well as CuO porous spheres and hexahedrons by controlling hydrogen diffusion in hydrazine hydrate solution and controlling oxygen diffusion in air, respectively. The formation of these transformations was also discussed in detail. Tested for Rochow reaction, the as-prepared Cu2O solid and CuO porous spheres exhibit higher dimethyldichlorosilane selectivity and Si conversion than Cu hollow spheres, which is attributed to the active sites for CH3Cl adsorption formed in CuxSi phase after the removal of oxygen atoms in Cn2O and CuO in the formation of dimethylchlorosilane. The present work not only develops a feasible method for preparing well shape-defined Cu2O solid spheres and hexahedrons but also clarifies the respective roles of Cu, Cu2O and CuO in dimethyldichlorosilane synthesis via Rochow reaction.大多数材料的功能和性质取决于它们的结构,而扩散机制是调控材料生长和结构的一个主要动力学因素.本工作提出了一条系统且可行的策略即通过控制扩散系数来制备Cu_2O固体球和六面体,且这些Cu_2O产物可以分别通过水合肼溶液中氢原子扩散控制和空气中氧原子扩散控制,转变成相应的Cu中空球和六面体,以及CuO多孔球和六面体.此外,对转变过程的微观机制作了详尽的讨论;用固定床评价了这些材料在用来合成有机硅行业广泛使用的单体的Rochow反应中的催化性能.结果表明,相较于Cu中空球,Cu_2O固体球和CuO多孔球表现出了更高的二甲基二氯硅烷选择性和硅粉原料转化率,这主要归因于在形成CuxSi活性相的过程中,Cu_2O和CuO中的晶格氧去除以后形成的表面氧缺陷可以作为反应物CH_3Cl的吸附活性位.该工作不仅提出一种制备规整Cu_2O固体球和六面体的可行方法,而且揭示了Rochow反应合成单体二甲基二氯硅烷中Cu,Cu_2O和CuO各自的催化作用.

关 键 词：cuprous oxide hollow spheres porous spheres surface oxygen vacancies Rochow reaction 

分 类 号：O643.36[理学—物理化学]