Cost-effective electrocatalysts for Hydrogen Evolution Reactions (HER): Challenges and Prospects

In the extant literature, a wide variety of processes for the production of H₂ can be seen but the active, cost-effective and stable metal electrocatalysts for hydrogen evolution reaction (HER) are essential ones to achieve sustainable energy systems. As such, Pt is a widely used electro-catalyst for HER but its cost is significantly higher that what it needs to be. Taking this as the main motivation, in this review, cheap and effective transition metals for cost-effective electrocatalysts for hydrogen evolution reaction were reviewed. On course of this exploration, transition metals such as molybdenum (Mo), tungsten (W) and composites such as reduced graphene oxide-supported PdAu nanoparticles and RuCo alloy nanoparticles embedded into N-Doped carbon were identified as some of the cost-effective electro-catalytic agents for HER. This review adds new insights into the stability and durability studies of these agents as well as prospects of their commercialisation and market readiness level for HER. Finally, a summary of the challenges in the future development of novel processing methodologies is presented which suggested that the artificial photosynthesis can be a very promising area of development.