Jellyfish bio-inspired Fe@CNT@CuNC derived from ZIF-8 for cathodic oxygen reduction

Biomimetics provides guidance to design and synthesize advanced catalysts for oxygen reduction reaction in microbial fuel cells (MFCs). Herein, jellyfish-inspired Fe clusters on carbon nanotubes connected with CuNC (Fe@CNT@CuNC) were designed and prepared by using zeolitic imidazolate framework (ZIF)-8 precursors to imitate the organic texture and function of jellyfish. The antibacterial effect of Cu⁺ ions depressed the growth of cathode biofilm to ensure rapid mass transport. Fe clusters and CuNC connected by CNTs accelerated the electron transfer from Fe to CuNC. The optimization of oxygen adsorption was caused by electron redistribution between sites of Fe and Cu. Jellyfish-like catalysts achieved a half-wave potential of 0.86 V and onset potential of 0.95 V vs. reversible hydrogen electrode (RHE). MFCs gained the maximum power density of 1600 mW·m⁻² after 500 h measurement. This work provides insights into the special design of advanced catalysts based on bio-inspiration and biomimetics.