Effect of Support for Non-Noble NiMo Electrocatalyst in Alkaline Hydrogen Oxidation

Abstract

The development of high-performance platinum group metal (PGM)-free electrocatalysts for the hydrogen oxidation reaction (HOR) in anion exchange membrane fuel cells (AEMFCs) remains a great challenge. Here, a novel design strategy for improving the catalytic activity of PGM-free catalysts by adopting N-doped large-porous carbon as a support material is reported. This paper shows the effect of support on the activity of non-noble NiMo in HOR by comparing NiMo alloy on N-doped mesocellular carbon foam (NiMo/N-MSUF-C) with NiMo/MSUF-C and NiMo on N-doped CMK-3 (NiMo/N-CMK-3). The strong interaction between NiMo and N species in N-MSUF-C alters the electronic structure of NiMo toward optimal binding energies for H and OH. The large pores in N-MSUF-C facilitate the diffusion of OH- into the catalyst layer, thereby increasing the limiting current density, which is higher compared with that of NiMo/N-CMK-3. The AEMFC with NiMo/N-MSUF-C as the anode shows a higher peak power density of 152 mW cm(-2) in H-2/O-2 compared with that of previously reported PGM-free catalysts. These results can lead to efficient designing of highly effective AEMFCs for practical applications.