Catalyst that changes itself could make green hydrogen cheaper

Reepresentative image (AI generated)

BENGALURU: Scientists in Bengaluru have discovered that a catalyst used to produce green hydrogen does something unexpected while on the job: it changes itself.The finding by researchers at the Centre for Nano and Soft Matter Sciences (CeNS), led by Neena S John and PhD scholar Palash Jyoti Gogoi, could help in designing more efficient and durable systems for producing hydrogen, a fuel widely seen as an important part of the transition away from fossil fuels.Hydrogen can be produced by splitting water into hydrogen and oxygen using electricity. When the electricity comes from renewable sources such as solar or wind power, the resulting fuel is known as green hydrogen.The challenge is that the process needs catalysts, materials that help chemical reactions occur faster and more efficiently. Scientists have traditionally viewed catalysts as stable substances that remain largely unchanged while carrying out their task.The new study shows that this is not always the case. Researchers examined molybdenum carbide, a catalyst that has attracted attention because it is relatively abundant and inexpensive compared with some alternatives.Using advanced techniques that allowed them to observe the material while it was working, they found that its structure changed during the hydrogen-producing reaction. Rather than harming performance, the transformation actually improved it.

As the reaction progressed, parts of the catalyst reorganised to form new active regions that were better suited to generating hydrogen. These newly formed structures played a crucial role in boosting both efficiency and stability.Researchers from CeNS, an autonomous institute of the Department of Science and Technology (DST), found a sharp contrast when they studied a related material. In that case, oxidation occurred too quickly, causing the catalyst to deteriorate and lose effectiveness over time.The comparison helped establish an important principle: not all changes inside a catalyst are bad. Some forms of transformation can enhance performance, while others can lead to degradation.“For scientists working on clean-energy technologies, this insight is significant. Much of catalyst research focuses on the material's structure before it begins operating. The new work suggests that the most important form of a catalyst may actually emerge only after the reaction starts,” as per DST.In other words, what matters is not simply what the catalyst is made of, but how it behaves under real-world conditions. The findings, published in the journal Materials Horizons, provide a clearer picture of what happens at the atomic level during hydrogen production and could guide the development of next-generation catalysts that are cheaper, more durable and more efficient.The CeNS team carried out the work in collaboration with Chandraraj Alex from Kiel University, Germany, and Satadeep Bhattacharjee and Swetarekha Ram from the Indo-Korea Science and Technology Center (IKST), Bengaluru.