In situ nanoarchitecturing and active-site engineering toward highly efficient carbonaceous electrocatalysts

Oxygen reduction reaction (ORR) lies at the heart of many renewable energy technologies. Development of facile approaches toward highly active carbon materials for ORR is urgently desirable. We accidentally discovered a method for preparing heteroatom-doped carbon catalyst through an in situ self-templating and self-sacrificing strategy during the carbonization of a single polymer precursor. The prepared N,S co-doped and hierarchical porous carbon possesses a large specific surface area up to 2446 m2 g−1, which is the state-of-the-art among the porous carbons prepared by direct pyrolysis of linear polymer precursors. The use of in situ nanoarchitecturing and active-site engineering ensures that the N,S co-doped porous carbon catalyst has sufficient active sites for charge/mass transport and catalysis. As expected, as-prepared carbonaceous electrocatalyst exhibited superior ORR activity in both alkaline and acidic electrolytes and outperformed the state-of-the-art benchmark Pt/C and the best carbonaceous electrocatalysts for ORR in aqueous media so far. Moreover, the N,S co-doped carbon catalyst was demonstrated to be a highly efficient air cathode for Zn–air batteries. Thus, this study provides a new and economical method of fabricating feasible carbon electrocatalysts with exceptional catalytic activities for energy conversion and storage.