Executive Summary : | The increasing global energy consumption and the climate change crisis have led to a shift towards renewable energy sources, such as green hydrogen produced from water electrolysis. However, green hydrogen is expensive, costing almost three times more than natural gas and producing significantly more greenhouse gas than grey or blue hydrogen. A significant portion of green hydrogen production relies on precious noble metal-based catalysts, which require regular replacement due to degradation. To make green hydrogen economically competitive, the cost of these catalysts must be reduced while also enhancing their efficiency and longevity. The surface area of a catalyst plays a crucial role in its overall efficiency, and the intrinsic catalytic activities of constituent elements are also important factors. strategies such as nano structuring and electronic designing have been applied to reduce the cost of noble metal-based catalysts and make them economically feasible. Nano structuring increases the specific surface area and active sites for catalysis, reducing the required catalyst content. Electronic design helps rationalize the amount of noble metals in the catalysts, optimizing the cost. While nano structuring has shown great potential, there is limited room for further size reduction and improvement in activity. On the other hand, nanosheets, being atomically thin and having co-ordinately unsaturated sites at the surfaces and edges, are promising candidates for enhanced electrocatalysis. Choosing earth-abundant elements as composition will further make nanosheets economically competitive. |