Hydrogels use sunlight for sustainable hydrogen production
Scientists have long tried to replicate how plants convert sunlight into energy, with the aim of developing renewable energy alternatives through artificial photosynthesis. This process uses sunlight to drive chemical reactions that produce clean energy. Yet developing synthetic systems that mimic natural photosynthesis has remained an elusive goal.
Now, researchers from the Japan Advanced Institute of Science and Technology (JAIST) and the University of Tokyo have introduced a bio-inspired hydrogel that can split water into hydrogen and oxygen using sunlight. This innovation marks significant progress in clean energy research, with hydrogen being recognized as a promising fuel source for the future. Unlike existing methods such as solar photovoltaics and electrolysis, which require external energy, this hydrogel system uses sunlight directly for water splitting, potentially increasing efficiency and reducing costs. The findings were recently published in ‘Chemical Communications’.
The team, led by Associate Professor Kosuke Okeyoshi, PhD student Reina Hagiwara at JAIST, and Professor Ryo Yoshida at the University of Tokyo, designed hydrogels with specialized polymer networks that facilitate electron transfer, a crucial component in water splitting. The hydrogels contain functional molecules, such as ruthenium complexes and platinum nanoparticles, that work together to mimic photosynthesis.
“The biggest challenge was figuring out how to arrange these molecules so that they could transfer electrons smoothly,” says Prof. Okeyoshi. “By using a polymer network, we were able to prevent them from clumping together, which is a common problem in synthetic photosynthetic systems.”
First author and Ph.D. student Reina Hagiwara emphasized: “What is unique here is how the molecules are organized within the hydrogel. By creating a structured environment, we have made the energy conversion process much more efficient.”
A major achievement of this research is the ability of the hydrogels to prevent the aggregation of functional molecules, a long-standing problem in artificial photosynthetic systems. This improvement led to improved hydrogen production, surpassing the performance of previous methods.
This development offers potential for transforming clean energy production. Producing hydrogen using only water and sunlight could pave the way for a sustainable energy future, replacing fossil fuels. “Hydrogen is a fantastic energy source because it is clean and renewable. Our hydrogels offer a way to produce hydrogen using sunlight, which could help sustainably reshape energy technologies,” said Prof. Okeyoshi.
While these findings are promising, the researchers acknowledge that further work is needed. Scaling up hydrogel production and ensuring long-term stability are the next steps. “We have shown the potential, but now we need to refine the technology for industrial use,” added Prof. Okeyoshi. “The possibilities are exciting and we are eager to move forward.”
Future efforts will also focus on improving the design of the hydrogels to further optimize energy conversion efficiency. The team’s commitment to advancing sustainable energy solutions remains steadfast.
Research report:Bioinspired hydrogels: polymeric designs for artificial photosynthesis