Composition-Tunable Co3-XFeXMo3N Electrocatalysts for the Oxygen Evolution Reaction

作者：Zhong, Chengzhi; Zhang, Jiaxi; Zhang, Longhai; Tu, Yuanhua; Du, Li; Cui, Zhiming^*; Song, Huiyu

来源：ACS Energy Letters, 2023.

DOI：10.1021/acsenergylett.3c00048

• NITRIDE NANOWIRES
• WATER OXIDATION
• EFFICIENT
• CATALYST
• SUBSTITUTION
• CO3MO3N
• SURFACE
• ARRAYS
• CO4N

The sluggish OER kinetics necessitates the development of highly active and durable electrocatalysts; however, an ideal alternative to expensive Ir/Ru-based and poorly conductive metal-oxide-based catalysts is absent. Herein, we demonstrate the class of nitrides prototype of Co3-xFexMo3N (0 < x < 3). These nitrides are cost-effective and highly conductive and have favorable composition flexibility. The optimized Co2.5Fe0.5Mo3N shows a mere overpotential of 218 mV at 10 mA cmgeo -2 and a robust durability at 100 mA cmgeo -2 over a 90-h measurement. Impressively, the water electrolyzer of Pt/ CiiCo2.5Fe0.5Mo3N only requires a cell voltage of 1.52 V to afford 10 mA cmgeo -2. XPS spectra and DFT calculation reveal that the partial Fe substitution not only increases the content of the active Co3+ species of Co2.5Fe0.5Mo3N but also upshifts the d band center of the Co site toward the Fermi level, which leads to the lower absorption energy of oxygen intermediates and hence substantially promotes the OER activity.