Researchers at Indian Institute of Technology (IIT) Guwahati have developed a new composite coating technology that could significantly improve the efficiency and durability of solar-driven water-splitting systems used for green hydrogen production.
The findings were published in the international journal Small in a study co-authored by Prof Uttam Manna and Prof Mohammad Qureshi along with researchers Dr Hrisikesh Sarma, Alpana Sahu, Anshika Chaudhary, Sumanta Sarkar, Sourav Mandal, and Lingaraj Sahoo.
According to the institute, the research addresses two major limitations in photo-assisted electrochemical (PAEC) water-splitting systems used for green hydrogen generation – peeling of catalyst layers from electrode surfaces over time and gas bubbles sticking to electrodes during reactions, reducing efficiency.
To overcome these issues, the research team developed a composite coating by combining graphitic carbon nitride, described as a two-dimensional photocatalyst, with a bubble-repellent hydrogel layer on porous nickel foam.
Unlike conventional methods where photocatalysts are applied as surface coatings, the IIT Guwahati team embedded the photocatalyst within the coating structure itself. The researchers said the design helped protect the catalyst from delamination while also increasing the electrochemically active surface area for water-splitting reactions.
According to the institute, the developed coating demonstrated around 51 per cent higher hydrogen production and 44 per cent higher oxygen production compared to conventional systems.
Speaking about the findings, Prof Uttam Manna from the Department of Chemistry said the incorporation of graphitic carbon nitride within a bubble-repellent matrix helped improve bubble departure frequency and enhanced photo-assisted electrochemical water-splitting performance.
“This strategy is broadly applicable, and many other catalysts may be explored in the future to further advance green hydrogen production,” he stated.
The researchers said the technology could have applications in next-generation clean energy systems, renewable energy storage technologies, and large-scale solar-to-fuel conversion devices.
Prof Mohammad Qureshi said future studies would focus on improving water-splitting efficiency further and scaling the system for larger electrodes and practical solar hydrogen production devices.
The study was conducted with support from the Anusandhan National Research Foundation (ANRF), the Ministry of Electronics and Information Technology, the Ministry of Education, and IIT Guwahati.