▎ 摘 要
Rational design and construction of robust electrocatalysts towards oxygen reduction reaction (ORR) are vital for energy conversion devices. Here, we report a hierarchically engineered Co nanoparticle (NP) encapsulated in Co, N codoped graphene-like carbon sample (Co@NC) via direct pyrolyzing the mixture of glucose, dicyandiamide and cobalt salt. Benefiting from the Co-N-4 moiety and high content of doped N species (8.81 at.%) which highly dispersed on the large Co NP modified carbon surface, Co@NC sample delivers remarkable ORR catalytic performance with an onset potential of 0.98 V and a half-wave potential of 0.86 V together with robust durability, which outperforms the benchmark Pt/C catalyst and most of published Co-N-x-C samples in alkali. This facile mass-producible strategy undoubtedly provides an avenue to achieve highly active and durable practical oriented electrocatalytic catalysts for wide electrochemical energy devices.