Triplet excitons on the interface of Colloidal Quantum Dots and organic molecules

Colloidal Quantum Dots (QDs) have been long-standing candidates for optoelectronic devices and applications, such as solar photovoltaic, light emitting diodes, detectors, and biological sensing. Theyare composed of semi-conductor materials, and are synthesized from solution. Their optical and electronic properties change with their size, shape, composition, and surface. In the up-conversion (UC) process two low frequency photons are converted in to one high energy photon, this can broaden the absorption spectrum and increase the efficiency of optoelectronic devices. One of the steps in the UC process is the transfer of high energy triplet exciton across the interface of colloidal QD/organic molecule. Using electronic structure calculations combined with experimental observations, we study and try to characterize triplet excitons on various QD structures ligated with organic molecules to get a better understanding of the transfer mechanism. We also use Molecular Dynamics simulations to study the morphology of these interfaces.