Led by Dr. Ashutosh K. Singh, the research team designed a state-of-the-art silicon-based photoanode using an innovative n-i-p heterojunction architecture, consisting of stacked n-type TiO2, intrinsic (undoped) Si, and p-type NiO semiconductor layers, which work together to enhance charge separation and transport efficiency.
The materials were deposited using magnetron sputtering, a scalable and industry-ready technique that ensures precision and efficiency. This thoughtful engineering approach allowed better light absorption, faster charge transport, and reduced recombination loss, key ingredients for efficient solar-to-hydrogen conversion.
“This is more than just a lab success. The device achieved an excellent surface photovoltage of 600 mV and a low onset potential of around 0.11 VRHE, making it highly effective at generating hydrogen under solar energy. Even more impressively, it showcased exceptional long-term stability, operating continuously for over 10 hours in alkaline conditions with only a 4 percent performance drop, a rare feat in Si-based photoelectrochemical systems,” noted a release by the Ministry of Science and Technology.
It further added that this new device is attractive for several reasons, including high efficiency, low energy input, robust durability, and cost-effective materials, all in one package. “It even demonstrated successful performance at a large scale, with a 25 cm2 photoanode delivering excellent solar water-splitting results,” it said.
Dr. Singh said, “By selecting smart materials and combining them into a heterostructure, we have created a device that not only boosts performance but can also be produced on a large scale. This brings us one step closer to affordable, large-scale solar-to-hydrogen energy systems.”
The work has been published in Journal of Materials Chemistry A, published by the Royal Society of Chemistry, and the researchers believe this is just the beginning. With further development, the technology could fuel hydrogen-based energy systems, from homes to factories, all powered by the sun.
