Researchers are currently exploring the use of molecular catalysts as a cheaper alternative to expensive noble metals in the electrolysis of water to produce green hydrogen. Noble metals like platinum and palladium are typically used as catalysts in this process, but their high cost makes the hydrogen more expensive.
A team from IIT-Bombay’s Department of Chemistry, led by Prof Arnab Dutta, has been investigating the use of a molecular catalyst called cobaloxime. This water-soluble catalyst is stable in air, making it easier to handle than noble metals. The researchers believe that strategic application of cobaloxime can make hydrogen production more efficient and cost-effective. They have published their findings in the journal Energy and Climate Change.
Although cobaloxime has been used as a catalyst in electrolysers before, the IIT-Bombay team has made modifications to its molecular structure to improve stability and reaction rate. By introducing natural amino acids, vitamins, and other functional groups, they have been able to increase hydrogen production while maintaining energy efficiency. They have also tailored cobaloxime to work in various water conditions, including seawater.
While cobaloxime is cheaper and easier to synthesize compared to noble metals, using it in industrial hydrogen production poses challenges. The team is working on modifying the structure of cobaloxime to make it compatible with electrodes and enhance stability, efficiency, and durability. Their goal is to make cobaloxime catalysts more suitable for industrial applications.
Currently, the team has found that cobaloxime performs well in both alkaline electrolysers and proton exchange membrane electrolysers. They are focused on developing an updated version of cobaloxime that can be used in heterogeneous conditions for industrial use.
Reducing the cost of green hydrogen production is crucial, especially for producing green steel. Green hydrogen, produced using renewable energy, is in demand for steel production as an alternative to coal. The researchers at IIT-Bombay believe that their work on cobaloxime catalysts could play a significant role in driving down the cost of green hydrogen.