Development And Application Of Atomically Dispersed Heterogeneous Catalysts Prepared Via Surface Immobilization Strategy

Heterogeneous catalysts with atomically dispersed active sites have always been one of the core issues of catalysis research,which are of great significance for the chemical industrial process.However,it is still a big challenge for the controllable design and large-scale synthesis of such catalysts.The preparation process of the existing atomically dispersed heterogeneous catalysts usually requires high temperature pyrolysis at 8001100℃.Under this condition,the active metal atoms are prone to migration and aggregation,and the structure of the support material tend to be damaged,which make it difficult to increase the active sites content of the catalyst.Besides that the yield for these catalysts is low due to the high reaction temperature,which hinders their large-scale application in industry.Here,based on the surface immobilization strategy,an economical and controllable strategy was developed for the preparation of catalysts with atomically dispersed active sites,in which the catalyst was prepared in a two-step method.First,the pre-organized M-Nx precursors were dispersed on the surface of layered Co-methylimidazole complex nanosheets,then the M-Nx sites were anchored on the nanosheets surface via organic chemical reactions under relative mild pyrolysis condition.The method is simple and controllable,and the prepared catalysts exhibit high stability,reproducibility of catalytic performance.The cheap starting materials,mild reaction conditions and facial process enable their largescale production.In terms of applications,compared with the commercial catalysts,the atomically dispersed heterogeneous catalysts not only exhibit excellent performance in electrocatalytic oxygen evolution,but also have high catalytic activity and selectivity in the catalytic production of βnitroalcohols from aromatic aldehydes and nitroalkanes.This surface immobilization strategy has provided a practical,economical and scalable way for the industrial production of monoatomic dispersed non-precious metal heterogeneous catalysts with controllable structure.