An account of metal and metal oxide based nanocomposite electrocatalysts for green hydrogen production

Hydrogen fuel is an emerging and critical pedestal on the pathway of a sustainable energy future with a goal of low-carbon energy fuel. Hydrogen fuel is a vital player to achieve the target of zero-emission fuel which is fulfilling the objective of the 2050 Paris Agreement. Therefore, with an increased demand for low or zero-carbon fuel, hydrogen will translate into a corresponding increased development in advanced technologies for its production. This review is focused on how to formulate advanced nanocomposite ink which is the main important content in the membrane electrode assembly (MEA) process and solar thermal splitting as an alternative route in the classification of hydrogen production methods. This review is accordingly sub-divided into a basic introduction of green hydrogen and its production methodology via electrolyzer technologies and emerging pathways; synthesis and classification of various metal oxide nanocomposites for green hydrogen applications followed by a brief account of electrocatalysts performance, efficiency, and stability for green hydrogen production. Where metal oxide nanocomposite electrocatalysts were the nucleus of discussion, which recently came into the limelight for investigating their potential to increase efficiency and lower the overall cost associated with green hydrogen production. Further discussion summarizes the present status, outlines the key bottlenecks, and future directions for research in metal oxide nanocomposite electrocatalysts for green hydrogen production with enhanced efficiency. • Metals and Metal oxides as electrocatalysts as the backbone of the electrolyzer. • Nanocomposites based on metals and metal oxides as alternative electrocatalysts. • Various approaches to green hydrogen production were discussed. • Green hydrogen production approaches are discussed, supporting zero carbon emissions.