Hyderabad: Scientists at the CSIR-Indian Institute of Chemical Technology (CSIR-IICT) have developed a low-cost copper-based photocatalyst that could help convert sunlight and seawater into clean hydrogen fuel, potentially reducing dependence on expensive precious metals in green hydrogen production, The Hindu reported.
The research team, led by scientist Ujjwal Pal and research scholar Bhavya Jaksani, studied a copper-titanium dioxide photocatalyst and found that its structure changes continuously during the hydrogen production process. Under sunlight, copper and titanium sites alter their oxidation states, improving the catalyst’s ability to generate hydrogen.
The researchers found that the catalyst becomes more active as its internal structure evolves during the reaction. Copper introduces small defects into the titanium dioxide framework, which improves charge movement and allows the material to absorb and utilise solar energy more effectively. This contributes to increased hydrogen production.
The study also showed that the catalyst’s long-term performance depends on factors beyond the material itself, including sunlight intensity and the availability of substances that promote the reaction.
Experiments conducted with natural seawater produced another important finding. Dissolved minerals and ions present in seawater were found to influence hydrogen generation by affecting interactions between the seawater and the catalyst surface. These components can therefore have a significant impact on the overall efficiency of the process.
The findings highlight the importance of studying photocatalysts under actual operating conditions rather than considering them as materials with fixed structures. Understanding how their structure and defects evolve during reactions could help researchers develop more stable, efficient and durable catalysts for solar hydrogen production.
The research could support the development of low-cost catalysts that reduce or eliminate the need for precious metals, potentially improving the economic feasibility of large-scale green hydrogen production.
The CSIR-IICT team is now working towards translating the laboratory findings into solar photoreactor systems designed for seawater and coastal applications.
“Our study shows that a photocatalyst is not a static material; its structure and defects evolve continuously during the reaction. Understanding and controlling these changes can help build more efficient and scalable seawater-to-hydrogen technologies,” said Ujjwal Pal.
