Light harvesting studies: Control over photophysical properties
A thorough understanding of the functioning of natural photosynthetic reaction centers reveals an important message: it is the assembly of different light-harvesting materials that participates in photosynthesis, rather than a single champion material. Inspired by this, our group is interested in creating an assembly of light-harvesting materials to maximize the efficiency of photophysical process. In such hybrid light-harvesting systems, it is important to control the interparticle interactions, as most of the photophysical processes are highly sensitive to the distance between the donor and the acceptor. A small change in the donor−acceptor distance (on the scale of a few angstroms) can have a big influence on the final outcome of a particular photophysical process. We aim to decorate the surface of quantum dots (QDs) with “ligand of choice” to control their interactions with other light-harvesting materials, and try to improve different fundamental photophysical processes such as energy & electron transfer, triplet-triplet annihilation, photoconductivity and so on.
As it is obvious by now, all the intriguing processes and functions reported in traditional QDs (Cd, Te, Se, Pb, etc.- based QDs) should be replicated in QDs containing environmentally friendly ions to realize practical applications from them. The impact of surface ligands and interparticle forces in controlling the direction of energy and electron flow in environmentally friendly InP and CuInS2 QDs has been demonstrate by our group. Along with regulating the efficiency of photophysical processes, a fine-control over electrostatic interactions helped in coupling both energy and electron transfer processes in a single QD nanohybrid system, which paved the way for the creation of high-contrast multicolor luminescent patterns.
The ultimate goal is to utilize the optimized materials and interactions to fabricate low cost & highly efficient light harvesting devices.
Students in-charge: Pradyut Roy