Quantum dot photocatalysis
Ability to play with the exotic photophysical and surface properties of quantum dots (QDs) have led the way of establishing the material as a potential photocatalyst in last two decades. In the era of global energy crisis, QDs and nanoparticles have proved to open up an efficient pathway for conversion of the solar energy to chemical equivalents. The aim of our work is to diversify the scope of the QD photocatalyzed transformations as well as understand the specific role of the QD surface for determining the fate of a reaction through QD-substrate interactions. Also, keeping the need of hour in mind, the choice of our QD systems is majorly influenced by the factor of lower toxicity of the ingredients towards environment.
In this direction, we have explored the potency of environmentally friendly indium phosphide/zinc sulfide quantum dots (InP/ZnS QDs) to photocatalyze two distinctly different reactions: metal-centred redox and carbon-carbon (C-C) coupling reactions. The surface chemistry of the QDs were successfully tuned to stabilize them in polar as well as in non-polar solvents. The QD was effective in photocatalyzing the metal centred one electron reduction reaction upto multiple cycles in presence of a sacrificial reagent, whereas, the redox neutral C-C coupling reaction was carried out by the QD in absence of any co-catalysts or sacrificial reagents.