Executive Summary : | Fossil fuel combustions have led to the depletion of conventional non-renewable energy resources and environmental pollution by releasing harmful CO2 emissions. Hydrogen, the cleanest fuel with the highest mass-energy density, is considered the cleanest alternative due to its low carbonaceous emissions. In the hydrogen evolution reaction (HER) process, hydrogen and oxygen are released in cathode and anode, respectively, by an electric current and suitable acidic/alkaline electrolyte. This produces clean and green hydrogen, suitable for membrane fuel-cells, industry feedstocks, and household purposes. To increase the efficiency of HER processes, suitable catalysts are required, and noble-metal-based catalysts like Pt have been considered. However, their high cost and scarcity of resources hinder their versatility in applications. Molybdenum disulfide (MoS2)-based catalysts have been considered as alternatives due to their abundance and low cost. Research has focused on exposing edge sites in MoS2 through nanostructuring techniques, but less attention has been given to basal plane sites, which are chemically inert. Researchers have developed techniques to activate inert basal planes by introducing sulfur vacancies, which promote hydrogen binding and favor HER. The current project aims to test or verify the most efficient active sites in MoS2 electrocatalysts by introducing sulfur vacancies in both basal plane dominated and edge-site dominated MoS2 nanostructures and compare their HER performance primarily through experiments. Proper knowledge of the dominant active sites in MoS2 will help in the efficient use of the electrocatalyst for HER applications. |