Phosphorus and iron doped nitrogen-containing carbon derived from biomass for oxygen reduction under various pH conditions

Abstract Various catalysts were synthesized by incorporating phosphorus and iron into nitrogen-containing carbon derived from shrimp shell with pyrolysis. These catalysts had high specific surface area, uniform atomic doping and various active sites, which resulted in the high kinetics activity towards oxygen reduction reaction (ORR) under various pH conditions. Based on different doping sources to analyse ORR activity, phosphorus-doped catalyst was suitable for alkaline medium and iron doping for acidic medium, while their synergistic effect induced the highest ORR activity in neutral medium. Besides, the stability measurements investigated their abilities for application. Introducing iron into nitrogen-containing carbon could gradually strengthen the long-term stability for different catalysts in various pH conditions. Especially, phosphorus doping promoted the best ORR performance in alkaline condition with an extremely poor stability, which could be overcome by further adding iron. This work provides a strategy for the doped biomass-based carbon to accommodate different fuel cells.