Hierarchical wood cells impose well-textured carbon nanotubes with cobalt single atoms: Bioinspired construction and application in zinc–air battery

The construction of oxygen reduction reaction (ORR) electrocatalysts with well-textured structure and desirable activity remains great challenge for the complicated procedures and poor interface. Herein, inspired by sea anemones, the highly ordered Co–based carbon nanotubes electrocatalysts were elaborately assembled on wood fibers via stoichiometry. The porous cell-wall and abundant oxygen groups in lignocellulosic scaffold impose such preferable structure, in which the Co–based carbon nanotubes with Co single atoms and Co nanoparticles were tuned to possess higher catalytic activity and capture more oxygen species. As expected, the as-prepared electrocatalyst displays outstanding ORR performance with a half-wave potential of 0.9 V. The assembled Zn–air battery using this cathode catalyst shows a high-power density of 196 mW cm−2, superior to the commercial Pt/C catalysts. This work could inspire developing other biomimetic architectures for high-performance energy storage and conversion systems.