ABSTRACT
With an increasing demand for an alternative to fossil fuels, hydrogen energy is found to be attracted significant attention as a green, clean, and sustainable fuel from the last few years. Hydrogen can be used in fuel cells which converts chemical energy to electrical energy directly. The best suitable method to produce hydrogen is by splitting water electrochemically or photo electrochemically in the presence of an electrolyzer or a photoelectrolyzer. The whole phenomena of the production of hydrogen to its application in fuel cells are the result of two major reactions, i.e., hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER). However, these two reactions are kinetically not feasible without a catalyst. Various methods have been developed in order to replace Pt which is the best catalyst so far for HOR reaction. In this chapter, we mainly focus on HOR, its mechanism along with various measurement activities, its catalytic activities, and their dependent controlling parameters. A detailed discussion also presented on different electrocatalyst like noble metals nanoparticles, graphene-based nanocomposites, non-precious electrocatalyst, etc. Some of the recent advances made on the catalytic performances, fuel cell efficiency will be included in the conclusion section.
