Regulating N-doped biochar with Fe-Mo heterojunctions as cathode in long-life zinc-air battery

Carbonaceous electrode loaded nano Mo 2 C-Fe 3 N@NCF was synthesized by solvothermal and pyrolysis from soybean straw for high-performance zinc-air batteries (ZABs). The empowered ZAB achieved 1.51 V open-circuit voltage, 88.40 mW cm −2 power density and over 1150 h cycle life. Density functional theory analysis indicates that charge transfer from Mo 2 C-Fe 3 N heterogeneous structure to N-doped biochar can significantly reduce the reaction barrier for oxygen reduction/evolution reactions, enhancing the adsorption of oxygen intermediates. Cellulose-derived carbon provides a large specific surface area, and N-doping enhances the conductivity of the resultant biochar, which both play a crucial role in the efficient loading of Fe and Mo active sites. This work inspires the design and application of interfacial engineering on low-cost biochar carriers.