摘要

Facile preparation of metal-free materials as efficient, stable and economical catalysts for oxygen reduction reaction (ORR) is highly desirable but remains challenging for metal-air battery and fuel cell applications. Herein, firstly through pyrolysing tea dregs with inorganic salts, we developed a simple approach to synthesize a heteroatoms quaternary-doped (B, N, P, S) porous carbon as a new metal-free ORR catalyst. Remarkably, after doping with heteroatoms, such prepared hybrid material displays significantly higher onset potential and limiting diffusion current density than the corresponding undoped carbon with similar specific surface area, and much better stability than commercial Pt/C catalyst in alkaline and even neutral solutions. Notably, when used in a Zn-air battery, our hybrid catalyst can reveal comparable open circuit voltage and power density, but better stability than these of Pt/C catalyst as well.