Liquid organic hydrogen carriers: New insights into catalytic activity for release and uptake of Hydrogen from the formate/bicarbonate cycle

Storage of hydrogen in liquid organic hydrogen carriers (LOHCs) provides a potential solution for the large scale, long-duration energy storage. Aqueous formate salts, are promising LOHCs for the transport and storage of H₂. The thermodynamics are favorable for reversible storage of hydrogen, providing the ability to release of H₂ at moderate temperatures, 35 – 85 °C, and pressures, 1 – 10 bar. They are non-flammable, environmentally benign and widely available in large scale quantities.
Hydrogen release from potassium formate has attracted considerable interest, with palladium-based nanoparticles on carbon supports (Pd/C) demonstrating superior performance compared to other catalysts. However, these catalysts face several deactivation issues. One of the primary challenges to make an impact on Energy Solutions for the Future is improving long-term stability across multiple cycles of hydrogen uptake and release. Our study focuses on investigating methods for the regeneration of Pd/C catalysts and enhancing their long-term stability by using promoters to address these deactivation issues and improve their stability in formate dehydrogenation. We will describe how our efforts to increase catalyst stability can provide a unique solution to large scale energy storage.