Boosting HER and OER on WSe2 nanoflakes via single-atom functionalization

Hydrogen is gaining attention as a sustainable energy source, and its efficient production relies on cost-effective electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in the water-splitting process. Meanwhile, transition metal dichalcogenide (TMDC) nanoflakes, with diverse shapes and sizes, are widely studied for their abundant active sites that boost catalytic performance. In this study, we employed density functional theory (DFT) to investigate the structural, electronic, and catalytic properties of WSe2 triangular nanoflakes. We also studied the impact of noble metal functionalization (Pd, Pt, Ru, and Rh) on the HER and OER activity of triangular nanoflakes. Our analysis revealed the presence of localized metallic states at the edges of the nanoflake, where catalytic activity is significantly higher compared to the bulk sites. Additionally, we found that noble metal functionalization greatly enhances catalytic performance. Among them, Pt-functionalized WSe2 triangular nanoflakes exhibit the most promising HER activity. Furthermore, the application of an external potential makes the OER process energetically favorable for Pd, Pt, and Rh functionalized nanoflakes. These findings highlight the potential of noble metal functionalized WSe2 triangular nanoflakes for efficient electrocatalysts in sustainable water-splitting processes.