Research Projects

Water electrolysis powered by renewable energy sources produces green hydrogen and it is estimated that to produce one kg of green hydrogen, it needs nine liters of clean water. These increasing global demand for clean water and sustainable energy require innovative technologies/systems capable of addressing these critical challenges simultaneously. Solar-driven photothermal systems, which make use of solar energy to produce local heat, have emerged as promising solutions for water purification and hydrogen production. Among these systems, plasmonic materials typically composed of noble metals such as gold, silver, or other nanostructures, have attracted significant attention due to their unique optical properties, which enable efficient light absorption to heat conversion, and enhanced catalytic activity. These materials exhibit localized surface plasmon resonance (LSPR), a phenomenon that enhances light absorption at specific wavelengths, this feature makes plasmonic systems highly efficient for dual functionalities such as photocatalytic hydrogen production and converting sunlight into thermal energy for photothermal applications In our previous reports, we have shown that the highly lossy non-metallic plasmonic titanium nitride (TiN) decorated porous alumina have more than 90% efficiency for solar to heat conversion and produce 1.5 L/h/m2 clean water from seawater area under 1 Sun illumination. Because of lossy nature of this TiN, it is capable of to produce local heat more than 200 oC by LSPR effect. Thus these lossy non-metallic plasmonic materials have great potential to produce clean water using solar-driven photothermal conversion processes. We have also developed a two-dimensional hydrogen boride (HB) nanosheets with unique structural feature and having 8.5 wt% hydrogen gravimetric capacity for on-board generation and storage of hydrogen at 200-250 oC. However, it requires external heater to raise the temperature of HB to produce the hydrogen and further we can regenerate hydrogen by treating it with water vapors. To generate and storage of hydrogen in HB nanosheets, it require high temperature and water vapors. In this work, we propose the development of a solar-driven plasmonic nanoheaters made up of lossy non-metallic material self-assemble sponge sheets capable of producing local temperature more than 250 oC. This plasmonic nanoheaters sponge will be used to produce the clean water and also by modifying this sponge sheet with HB or hydrogen releasing materials such as ammonia borane etc. to generate and store the hydrogen. By integrating photothermal conversion and catalytic hydrogen generation, this approach offers a sustainable, cost-effective, and environmentally friendly solution to global challenges. This study aims to optimize the design and performance of the plasmonic materials, maximize solar energy utilization, and ensure scalability and adaptability for real-world applications.