Recently, Prof. Zhao’s group constructed carbon based nanowire electrocatalysts with high concentration of metal sites and catalytic activity by self-assembly technology. The paper entitled “Self-assembly Induced Metal Ionic-Polymer Derived Fe-Nx/C Nanowire as Oxygen Reduction Reaction Electrocatalysts” was published on Journal of Catalysis (impact factor = 7.88).
Article link:
https://www.sciencedirect.com/science/article/pii/S0021951720303274
Metal/nitrogen co-doped carbon (M-Nx/C) materials show good catalytic activity for electrochemical/chemical reactions in energy conversion devices and organics synthesis. However, the preparation of M-Nx/C materials involves a high-temperature pyrolysis step in which not only M-Nx/C active sites but also more inactive metal group aggregates are generated. In addition, the synthesis of M-Nx/C materials with specific nanostructures is limited by the original nanostructures of the precursors, which makes it difficult to achieve controlled synthesis. Therefore, the preparation of M-Nx/C materials with high density of M-Nx sites and specific nanostructures remains a challenge in the field of catalysis.
Schematic diagram of the synthesis of M-Nx/C catalysts for the preparation of self-assembled induced metal ionomer polymers
In this work, Yong Zhao's group reported a strategy for the preparation of M-Nx/C catalysts using self-assembled induced metal ionomers. The method can not only preferentially generate M-Nx sites by inhibiting metal aggregation during pyrolysis, but also generate different nanostructured M-Nx/C catalytic materials. Taking the preparation of Fe-Nx/C as an example, the nanosheets obtained from the self-assembly of [Fe(CN)6]4-·{[(C6H4-NH3)2]2}4+ compounds were used as precursor materials, and the precise synthesis of metal ion polymer nanowires and nanoparticles was achieved by controlling the oxidative polymerization temperature. Fe-Nx/C nanowires and nanoparticles catalytic materials with high concentrations of monometallic atoms were prepared by using them as precursors, respectively. The Fe-Nx/C nanowires were shown to have excellent catalytic activity for oxygen reduction reactions in both acidic and basic media. This work provides a new idea for the preparation of M-Nx/C catalysts with special morphology and high activity.
Xuebing Zhu, a doctoral student in the Laboratory of Special Functional Materials, is the first author of the paper, and Dr. Yong Zhao is the corresponding author of the paper. This work was supported by the National Natural Science Foundation of China, the Science and Technology Department of Henan Province, the Education Department of Henan Province and Henan University.