NIRLAMS. NIR Light Harvesting in Artificial Protein-Lipid-Chromophores Coassembled Molecular System

The depleting fossils fuels added by their high carbon emission have been constantly putting pressure on scientific community to find an economic solution in the form of green energy. The utilization of everlasting solar energy is possible solution which has been researched for a long now but has constraints of Shockley Queisser Limit. The recent emergence of photon upconversion has given hope to overcome this limit by upconverting the transmitted sub band gap photons to band gap responsive light. Among the existing UC phenomenon triplet-triplet annihilation based photon upconversion (TTA-UC) leading the way because of its function at sub solar irradiance and 1.5 solar spectrum. Most of the TTA-UC systems are limited to Vis to Vis UC which though have contributed immensely for conceptual development of the filed; however for practical applications in photonic devices NIR to Vis TTA-UC would be more ideal. This is because; (1) NIR is low energy non-invasive light which is useful for biological applications and (2) can overcome the Shockley Queisser Limit of solar cells. On the other hand NIR to Vis TTA-UC systems are although reported they are mostly limited to deoxygenated organic solvents which have limitation of device fabrication. This is due to low solubility of NIR to Vis dyes in synthetic polymers and quenching by molecular oxygen. Therefore, the present proposal is aimed at overcoming these issues by introducing an innovative approach of protein-lipid-chromophores co-assembly both for aqueous and solid state NIR to Vis TTA-UC in oxygenated environment. The proposed approach is supported by the fact that nonpolar domains of protein-lipid coassembly can solubilize the hydrophobic NIR to Vis dyes and thick H-bonding network of protein can prevent oxygen inflow into chromophore region. The proposed project would lead to a new conceptual development for efficient solar upconversion and will broaden the solar light harvesting range for solar energy conversion system