Finding the catalytically active sites on the layered tri-chalcogenide compounds CoPS3 and NiPS3 for hydrogen evolution reaction

Electronic structure calculations based on density functional theory are used to identify the catalytically active sites for the hydrogen evolution reaction on single layers of the two transition metal tri-chalcogenide compounds CoPS3 and NiPS3. Some of the under-coordinated P and S atoms at the edges are found to act as the active sites, the details of which depend on the coverage of H on the electrode. Overpotentials along the two possible pathways for HER are also estimated for the two materials. These findings not only resolve an apparent discrepancy between published experimental results and our earlier calculations, but also provide insights which can be used to enhance catalytic efficiency of these materials further.

Automated summary

Density functional theory calculations were used to identify catalytically active sites for hydrogen evolution reaction on single layers of transition metal tri-chalcogenide compounds CoPS3 and NiPS3. The under-coordinated P and S atoms at the edges were found to act as active sites, depending on the coverage of H on the electrode, and overpotentials for HER were estimated for the two materials. These findings resolve discrepancies between experimental results and earlier calculations, and offer insights for enhancing catalytic efficiency of these materials.