Innovative synthesis of cobalt-based catalysts using ionic liquids and deep eutectic solvents: A minireview on electrocatalytic water splitting

Abstract

In recent years, ionic liquids (ILs) and deep eutectic solvents (DESs) have demonstrated significant potential in the field of high-efficiency cobalt-based catalyst preparation due to their unique physicochemical properties. These solvents not only serve as reaction media but also as templating agents and can even directly participate in chemical reactions as reactants, offering a distinct advantage over conventional solvents in enabling multi-functional catalyst design. Through the application of ILs and DESs, researchers have successfully synthesized novel structured and high-performance cobalt-based catalysts that exhibit excellent performance in water splitting reactions. Notably, the tunability of ILs/DESs enables heteroatom doping (P, S, N), revealing synergistic effects on catalytic activity and atom economy, which are rarely discussed in previous literature. This article discusses in detail various synthesis methods, including electrodeposition, solvothermal synthesis, and others, clarifying how ILs/DESs act as both synthetic tools and performance modifiers in the context of electrocatalytic water splitting. Additionally, the article provides an outlook on future research directions, emphasizing the importance of further optimizing catalyst performance, improving synthesis efficiency, and exploring more environmentally friendly synthesis strategies.