Iron phosphide/N, P-doped carbon nanosheets as highly efficient electrocatalysts for oxygen reduction reaction over the whole pH range

Abstract Developing electrocatalysts with both high activity and low cost for oxygen reduction reaction (ORR) has attracted much attention. Herein, we fabricated iron phosphide/N, P-doped carbon nanosheets electrocatalysts via a one-pot pyrolysis process without any post-treatments, which shows high ORR activity over the whole pH range. In alkaline solution, the optimal catalyst exhibits almost the same onset potential (0.918 V vs RHE) and half-wave potential (0.832 V vs RHE) with commercial Pt/C (20 wt %), meanwhile it shows prominent catalytic activity compared with Pt/C in acidic and neutral media. Noteworthy, the catalyst catalyzes ORR process following a one-step 4e pathway in all these media and poses better tolerance toward methanol and greater durability than Pt/C. It was proved that Fe x P (x = 1 or 2) and N, P-doped carbon synergistically contributed to the high ORR activity for the electrocatalysts. This work would broaden the application of iron phosphides in the field of electrocatalysis.