Engineering the performance of bifunctional oxygen electrocatalysts by modulating the atomically dispersed Co,Ni on N-doped cotton biomass aerogel of carbon fiber catalysts for rechargeable zinc-air battery

Rational construction of advanced bifunctional catalysts with dual-active-sites is still challenging for both oxygen reduction (ORR) and oxygen evolution reactions (OER).The design of metal single atom catalysts prepared through high-temperature gas transport is an emerging method. The CoNi-N-C catalyst was prepared by using Co powder and Nickel foam to volatilize atomic dispersed Co,Ni element embedded in nitrogen doped cotton biomass biomass aerogel of carbon fibers in a high temperature tubular furnace in ammonia atmosphere. In this work, CoNi-N-C-1000 monoatomic catalyst was successfully synthesized by using the above method The resulting CoNi-N-C-1000 exhibited excellent bifunctional catalytic performance for ORR (E 1/2 =0.85V) and OER (E j=10 =1.54V) in alkaline electrolytes, which can compete with previously reported bifunctional electrocatalysts. In addition, compared to the Pt/C+RuO 2 mixed catalyst, this bifunctional catalyst can endow the self-made zinc-air battery with better power density (128.5 mW/cm 2 ) and cycle stability (142.3 hours), demonstrating its potential feasibility in practical applications of rechargeable zinc-air batteries.