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

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2024-11, Vol.500, p.157463, Article 157463
• Main Authors: Meng, Xiao-ru, Gao, Shuai, Liu, Nianxi, Wu, Pei-dong, Fang, Zhen
• Format: Article
• Language: English
• Subjects: Carbonaceous cathode; Cellulose; Iron-molybdenum bimetallic; Metal-air battery; Oxygen electrocatalysts
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.157463

[Display omitted] •Nano carbon fiber-supported Fe-Mo cathode is synthesized from soybean straw.•Mo2C-Fe3N heterogeneous structure exhibits excellent bifunctional catalytic activity.•N-doped biocarbon possesses high conductivity and oxygen transport capability.•Charge transfer from Mo2C-Fe3N to N-doped biochar enhances the adsorption of intermediates.•Zinc-air battery demonstrates superior capacity (769.78 mAh g−1) and lifetime (>1150 h). Carbonaceous electrode loaded nano Mo2C-Fe3N@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 Mo2C-Fe3N 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.