Nitrogen-doped nanoporous carbon derived from waste pomelo peel as a metal-free electrocatalyst for the oxygen reduction reaction.

The development of a new catalyst for the low-cost, environmentally friendly and highly efficient oxygen reduction reaction (ORR) is important for the commercialization of fuel cells. Herein, a smart strategy was proposed for the preparation of a novel nitrogen-doped nanoporous carbon (N-PC) using resource-rich pomelo peel, a type of waste, as starting material. The typical product (N-PC-1000) possesses a high BET surface area (up to 1444.9 m2 g(-1)), porous structure and high graphitic N content. In alkaline and acidic media, the N-PC-1000 shows not only decent catalytic activities in terms of onset potential and current density, but also has excellent tolerance to methanol poisoning effects and durability. This study provides worthy inspiration for using other environmental wastes to prepare related functional carbon materials with a variety of promising practical applications such as supercapacitors and lithium-ion batteries.