Two-Dimensional Amorphous Cr2O3Modified Metallic Electrodes for Hydrogen Evolution Reaction

The surface modification of benchmarked metal catalysts using nanostructured non-metallic materials for improved performance and stability is an active area of research and is interesting from both a fundamental and an applied perspective. Amorphous few layered nanosheets of Cr2O3(3-5 nm) are synthesized by rapid thermal exfoliation of CrCl3 center dot 6H(2)O precursors and are characterized. The hydrogen evolution reaction (HER) studies on alkaline medium conducted with platinum and gold electrodes modified with amorphous sheets of Cr(2)O(3)show augmented HER activity compared to the pristine ones while Cr(2)O(3)alone is not HER active. The role of amorphous Cr(2)O(3)as a co-catalyst is established and the synergistic charge transfer effects while coupling Cr(2)O(3)with metal catalysts are studied using electrochemical impedance spectroscopy. Large-scale processability of amorphous Cr(2)O(3)by rapid thermal treatment along with its high electrochemical stability (>2000 cycles or >50 h) in harsh alkaline conditions, where benchmarked metals fail, open new avenues in designing novel scalable catalysts by protecting the surface of noble metal catalysts without sacrificing the electrochemical performance.