Catalytic Properties of Vanadium Diselenide: A Comprehensive Study on Its Electrocatalytic Performance in Alkaline, Neutral, and Acidic Media

Abstract

Here, we report the synthesis of vanadium diselenide (VSe₂) three-dimensional nanoparticles (NPs) and two-dimensional (2D) nanosheets (NSs) utilizing nanosecond pulsed laser ablation technique followed by liquid-phase exfoliation. Furthermore, a systematic study has been conducted on the effect of NP and NS morphologies of VSe₂ in their catalytic activities toward oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) under alkaline, neutral, and acidic conditions. Research on VSe₂ clearly demonstrates that these morphologies do not have a significant difference for ORR and OER; however, a drastic effect of morphology was observed for HER. The ORR activity of both NSs and NPs involves ∼2.85 numbers of electrons with the Tafel slope of 120 mV/dec in alkaline and neutral pH. In alkaline solution, NPs are proved to be an efficient catalyst for OER with an onset potential 1.5 V; however, for HER, NSs have a better onset potential of -0.25 V. Moreover, the obtained NPs have also better catalytic activity with a 400 mV anodic shift in the onset potential compared to NSs. These results provide a reference point for the future application of VSe₂ in energy storage and conversion devices and mass production of other 2D materials.