Highly performed nitrogen-doped porous carbon electrocatalyst for oxygen reduction reaction prepared by a simple and slight regulation in hydrolyzing process of ZIF-8

Abstract

A simple and environmentally friendly method to prepare nitrogen-doped porous carbon (NPC) electrocatalysts for oxygen reduction reaction (ORR) is studied by using glucose (Glu) to regulate the hydrolyzing process and structure of ZIF-8 precursor. Compared with pristine ZIF-8, the ZIF-8 regulated by Glu (Glu/ZIF-8) has smaller particle size. NPC has a higher content of mesopores and macropores, a higher degree of graphitization, and a higher content of pyridine and graphitic nitrogen than nitrogen-doped carbon (CN) derived from prisitine ZIF-8. The onset potential, half-wave potential, and limiting current of NPC for ORR in 0.1 ​M KOH medium is 0.99 ​V, 0.88 ​V, and 5.43 ​mA ​cm−2, respectively. The electrocatalytic performance of NPC is similar to Pt/C, and better than CN. Furthermore, its stability and resistance to methanol are better than Pt/C. Its high electrocatalytic performance is attributed to the effect of Glu on the structure of ZIF-8 precursor.