Amorphous Rhenium Disulfide Nanosheets: A Methanol-Tolerant Transition Metal Dichalcogenide Catalyst for Oxygen Reduction Reaction

Abstract

A methanol tolerant catalyst for the reduction of oxygen is important for the effective utilization of direct methanol fuel cells (DMFCs). Herein, the synthesis of a layered transition metal dichalcogenide rhenium disulfide (ReS2) and its utilization as an effective novel precious metal free, methanol tolerant oxygen reduction catalyst is reported. A single step wet chemical synthesis procedure is used to synthesize ReS2, and morphological analysis revealed the formation of ultrathin nanosheets of thickness 1.6 nm. The catalytic activity of ReS2 toward the oxygen reduction reaction (ORR) was monitored in 0.1 M H2SO4, which showed higher current density and excellent stability comparable with the commercially available carbon supported platinum catalyst. The catalyst exhibited selective 4 electron transfer kinetics (n = 3.9) and has remarkable tolerance to methanol in contrast to platinum supported on carbon, which makes it promising as a Pt-free methanol tolerant ORR catalyst.