Localized micro-deflagration induced defect-rich N-doped nanocarbon shells for highly efficient oxygen reduction reaction

Abstract

Defect engineering is capable of significantly enhancing catalytic performance of target materials, but very few high efficiency defect-engineered catalysts were reported due to the lacking of systematic and comprehensive understanding of defect effect, as well as controllable experimental practice. Here, we reported high-efficiency oxygen reduction reaction (ORR) nanocarbon shell electrocatalyst, using a unique localized micro-deflagration strategy combined with postprocessing of heat treatment. This micro-deflagration allows the ultrafast and large scale formation of highly porous nanocarbon structure with rich nitrogen doping, where parts of nitrogen can be further removed via post heat treatment for constituting targeted active sites of defects for ORR. The defective nanocarbon shells demonstrate large specific surface area (540 m2g-1) with 6.05 at% N-doping, which allows exceptional electrocatalytic activity (Eonset of 0.89 V vs.RHE, E1/2 of 0.79 V vs.RHE and Jk of 5.26 mA cm−2), long-term stability, and tolerance to crossover effect, comparable to commercial Pt/C in alkaline electrolyte. Most importantly, this localized micro-deflagration is significantly enriched the research of defect engineering chemical electrocatalyst, and great promising for the synthesis of other metal-free nanocarbon materials.