Abstract

Hydrogen is a clean, renewable, and sustainable carrier of energy, with high energy density and zero carbon emissions, however, production of hydrogen efficiently and at a low cost is still a great challenge. Atomically dispersed catalysts (ADCs) have received much interest because they exhibit the highest degree of atomic utilization and active sites as well as catalytic activity and stability over time, and are ideal in hydrogen evolution reactions (HER). This paper experimentally tested 50 ADCs (noble metals (Platinum, Palladium, Ruthenium) and transition metals (Nickel, Cobalt)) in their spatial distribution, hydrogen evolution rates and their stability in controlled laboratory environments. Platinum-based ADCs were found to have the highest hydrogen evolution rate (120 mmol H 2 g -1 h -1), efficiency (95), and stability (92) followed by Palladium and Ruthenium, whereas transition metals had moderate catalytic capacity and large activities loss. The results indicate the higher efficiency and long life of noble metal ADCs, and that special attention should be paid to the selection of catalysts to enhance hydrogen generation. The study will provide important details on how the cost-effective, high-performance, and stable catalysts can be developed to advance to designing of sustainable hydrogen power systems.