“…These non-metal heteroatoms are usually introduced into pure carbon to form RMAB airelectrode catalysts through doping strategies. As identified, dopants can act as a secondary phase; providing adsorption structures for charge transfer and improving electrocatalytic activities of ORR and/or OER [21,22]. Recently, various carbon materials (e.g., porous carbon materials, CNT, graphenes, carbon fibers, carbon xerogel, carbon aerogel, nanocage carbons, carbon nano-onions) have been explored as heteroatom-doped carbon catalysts for BMABs and the results show that these composited carbon materials exhibit desirable characteristics such as desirable pore size/volume, large surface area, and high stability.…”