Researchers from the Centre for Nano and Soft Matter Sciences (CeNS), Bengaluru, an autonomous institute under the Department of Science and Technology, have developed a novel metal-free approach for green hydrogen production through solar-driven water splitting. The team integrated naturally occurring aspartic acid with a light-absorbing organic molecule called perylene diimide (PDI), allowing the molecules to spontaneously organize through supramolecular self-assembly into highly ordered two-dimensional nanosheets in water.
The research demonstrated that this molecular reorganization dramatically broadened light absorption, enhanced charge separation, reduced energy losses, and increased the accessible surface area for catalytic reactions without altering the molecule's chemical composition. The self-assembled material generated nearly 18% higher photocurrent than its bulk counterpart during solar-driven water splitting experiments. Advanced electrochemical measurements together with density functional theory calculations revealed that self-assembly promotes more efficient charge transport, while the amino acid increases the molecular dipole moment, facilitating effective separation of photo-generated charges that drive hydrogen evolution.
This breakthrough represents a significant advancement in developing efficient, environmentally friendly, and metal-free photocatalysts for solar energy conversion, potentially reducing dependence on costly and scarce metals. The work was published in the Journal of Materials Chemistry A, a leading Royal Society of Chemistry journal, with the research team led by Dr. Goutam Ghosh and Dr. Ashutosh K. Singh, along with researchers Sourav Moyra, Kumar Shubham, and Athira Chandran M. Such materials could contribute to future technologies for green hydrogen production, artificial photosynthesis, solar fuel generation, and next-generation renewable energy devices.