One-step construction of multi-doped nanoporous carbon-based nanoarchitecture as an advanced bifunctional oxygen electrode for Zn-Air batteries

Fabrication of multi-doped catalysts generally involves complex and energy-intensive processes including the preparation of special precursor, solvent evaporation, and post separation or treatment. Herein, we have developed an eco-friendly one-step process to effectively regulate the electronic structure of products by combining the concepts of alloy, heteroatoms doping, phase controlling and heterostructures. The obtained CoFe and Cog nanoparticles encapsulated in multi-doped nanoporous carbon (NPSC-Co2Fe1) exhibits a small potential gap between E-j=10 and E-1/2 of 0.75 V for bifunctional electrocatalytic O-2 redox reactions. It is revealed that defect-rich multi-doped carbon-based nanoarchitecture and electronic redistribution provide more donor-acceptor active sites with reduced energy barrier. Notably, ZABs using NPSC-Co2Fe1 as air electrodes exhibit outstanding charge-discharge performances and cycling stability superior to those of ZABs with Pt/C-IrO2. The flexible all-solid-state ZABs with NPSC-Co2Fe1 operate stably even under bending state. Moreover, these batteries are implemented to power mini-fans and LED panels.