Executive Summary : | Hydrogen is a platform chemical, which is currently produced by steam-methane reforming at high temperatures of 700-1000oC and high pressure of 3-25 bar in the presence of a catalyst, but with large carbon footprint. Importance of H₂ lies in its maximum energy (121 MJ/kg) released per unit mass during combustion, compared to any other petroleum derived fuel (48 MJ/kg for petrol). However, production of H₂ in a sustainable manner from renewable resources without adding to the carbon footprint is a game-changing challenge.[1] While solar hydrogen production through water dissociation by artificial leaf concept has its bottlenecks and has reached only 1-2% even after 5 decades of its discovery, electrochemical splitting is potentially robust method to convert electrical energy into chemical energy. Moreover, H2 burning gives energy and it produces water as the only side product, and hence contributing to improve the environment towards being clean. H₂ produced by water electrolysis would contribute to reduce the carbon footprint significantly. As a clean fuel, hydrogen would contribute not only to all oil industries in many different ways, but to the whole nation and globe. In fact, electrochemically produced H₂ can be considered as future fuel and it is a substitute for the conventional (petroleum derived) hydrogen sources in the short to long terms.[2] While the benchmark catalysts for water splitting are based on the noble metals such as Pt/C, IrO₂ and RuO₂, their scarcity and cost limit the practical applications. Till date few catalysts have shown very good efficiency for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) but with expensive components and restricted operational stability. Catalysts like FeCoW hydroxide on gold foam, Ir₃V, CoRu etc. have shown very promising results but still Pt-like activity at higher current densities with long term durability are yet to be achieved. In these contexts, the ABO₃ type perovskite oxides have appeared as economical electrocatalysts because of their important properties like creation of redox couples, adjustable structural imperfections, good ionic conductivity etc. The activity of the perovskite materials can be further improved by creating metal nanoparticles on the surface by exsolution. The target of this project is to conduct overall water splitting at a very low cell voltage such as 1.5V. To achieve a lower cell voltage both the HER and OER catalyst should be ultra-efficient to meet the need of a full cell electrolyzer. The novelty of our approach is not only based on the catalyst’s design and its activity, but also ease of the synthesis and long-term durability. References: [1] M. Cabán-Acevedo, M. Stone, J. Schmidt, J. Thomas, Q. Ding, H. Chang, M. Tsai, J. He, S. Jin, Nat. Mater. 2015, 14, 1245. [2] T. Jaramillo, K. Jorgensen, J. Bonde, J. Nielsen, S. Horch, I. Chorkendorff, Science, 2007, 317, 100. |