Bimetal Metal-Organic Frameworks Derived Hierarchical Porous Cobalt@Nitrogen-Doped Carbon Tubes as An Efficient Electrocatalyst for Oxygen Reduction Reaction

作者：Xu, Yuting; Mou, Jirong; Liu, Ting; Li, Mei; Pan, Wenhao; Zhong, Lei; Huang, Jianlin^*; Liu, Meilin

来源：ChemElectroChem, 2022, 9(6): e202101310.

DOI：10.1002/celc.202101310

• zeolitic imidazolate frameworks
• hollow carbon tubes
• hierarchical porous structure
• Co NPs embedded in N-doping carbon
• ORR

The design and preparation of inexpensive, stable, and superior catalysts for the oxygen reduction reaction (ORR) are significant but challenging towards sustainable energy conversion technologies. Herein, a tubular template-assisted strategy for fabrication of cobalt nanoparticles (Co NPs) embedded in one-dimensional (1D) N-doped porous tubular carbon composites (Co@N-CTs) is developed via in-situ growth of bimetallic zeolitic imidazolate frameworks (ZnCo-ZIFs) on hollow polypyrrole (PPy) nanotubes surface. The PPy can not only act as a hollow tubular template, but also efficiently inhibit aggregation of Co NPs. Thanks to the 1D tubular interconnected networks and abundant micro-/nano- porous tube wall structure, the as-prepared Co@N-CTs catalyst achieves outstanding ORR performance with an onset potential (E-0) of 0.982 V and a half-wave potential (E-1/2) of 0.864 V. Meanwhile, the Co@N-CTs catalyst also demonstrates superior durability with slightly decay of 3 % of initial current over 40000 s, as well as tolerance to the methanol. Furthermore, the Co@N-CTs cathode exhibits a large specific capacity (784 mAh g(-1)) and satisfying power density (116 mW cm(-2)) in a Zn-air battery.