IIT-Guwahati develops low-cost catalyst for hydrogen production from water

Researchers at the Indian Institute of Technology-Guwahati have developed a low-cost catalyst to produce hydrogen from water, a development that could support India's National Green Hydrogen Mission and accelerate the shift towards sustainable energy, the institute said.

Hydrogen is considered a key component of the global transition to clean energy as its use for power generation produces water as the only byproduct. It is also widely used in fuel cells and as a raw material in industries, including fertiliser manufacturing.

However, around 90-95 per cent of hydrogen is currently produced from fossil fuels. Production of grey and blue hydrogen from natural gas and brown and black hydrogen from coal releases greenhouse gases.

Producing hydrogen from water through electrolysis is a cleaner alternative but requires efficient catalysts. Existing high-performance catalysts often rely on rare and expensive noble metals, limiting their large-scale deployment.

To address this challenge, IIT-Guwahati researchers used inexpensive and widely available nickel salt as a key component of a water-splitting catalyst. They combined it with an anthracene-based organic molecule to improve efficiency and stability.

The team developed a coordination polymer-based catalyst in which anthracene units are interlinked through nickel nodes. The material was synthesised through a simple process at room temperature using ultrasonic waves, said Akshai Kumar, associate professor in the Department of Chemistry at IIT-Guwahati, who led the study.

The structure creates a high density of active sites for the hydrogen evolution reaction and enables efficient electron transport through the material, Kumar said.

The researchers found that the catalyst remained stable during long-term operation and that nearly 88 per cent of the electrical energy supplied was utilised in splitting water.

"This low wastage is essential to develop practical systems for large-scale hydrogen production," the institute said.

Kalishankar Bhattacharyya, assistant professor in the Department of Chemistry, said the study showed a significant synergistic effect between nickel and the anthracene-based framework, with each component enhancing the performance of the other.

Chemical analysis and modelling studies showed that the nickel atoms formed a three-dimensional network with the anthracene moiety, helping explain the catalyst's performance.

The findings have been published in the *Journal of Materials Chemistry A*. The paper was co-authored by Kumar and Bhattacharyya, along with research scholars Niharika Tanwar, Jumana Ishrat and Khadimul Islam.