A highly stable spherical FeCo-N-C cathode catalyst for zinc-air batteries prepared by a template-assisted method

Ferrum -cobalt nitrogen-doped carbon (FeCo-N-C) catalysts have emerged as highly promising cathode catalysts for zinc-air batteries due to their exceptional oxygen reduction reaction (ORR) catalytic activity and stability. A porous spherical structure can be synthesized through a hydrothermal treatment of glucose assisted by a silica (SiO₂) template, followed by further thermal treatment. When assembled into a zinc-air battery, this porous spherical structure facilitates charge transfer and enhances the absorption of O₂ at active sites. By optimizing the metal salt ratio, the Fe₂₈₀Co₂₀₀-N-C catalyst was identified as exhibiting the best performance. Moreover, the assembled zinc-air battery demonstrated remarkable stability across various current densities (2, 5, 10, 20, and 50 mA cm⁻²). Notably, the voltage plateau remained stable at 0.9 V even under a high current density of 50 mA cm⁻². At a current density of 10 mA cm⁻², the battery maintained a stable voltage plateau of 1.1 V after 100 h of discharge and 100 charge/discharge cycles (totaling 33 h). In comparison to non-metal-doped samples, the FeCo-N-C catalyst exhibited significantly superior stability, highlighting its potential for practical applications in zinc-air batteries.