Carbon-pore-sheathed cobalt nanoseeds: An exceptional and durable bifunctional catalyst for zinc-air batteries

Exceptional and durable catalysts for Zinc-air batteries are plagued by nanoparticle agglomeration. As a proof-of-concept, we designed carbon-pore-sheathed cobalt nanoseeds by loading cobalt nanoparticles into N-doped defective carbon pores. Introduced N-doping, Co–N–C bond and graphitic/graphenic carbon defects endow the catalyst with exceptional catalytic activity. Most importantly, the design of Co confined within carbon pores effectively solved the dilemma of nanomaterial stability. By balancing the high catalytic activity and stable cyclability, this unique catalyst is among the outstanding bifunctional catalysts, with a high ORR half-wave potential of 0.847 V and a low OER potential at 10 mA/cm2 of 1.593 V. As demonstrated in the full cell, a peak power density of 135 mW/cm2 at a current density of 200 mA/cm2 and 450 h of stable cycling performance without fading at a current density of 30 mA/cm2 was delivered.