Hole transport mechanism in organic/inorganic hybrid system based on in-situ grown cadmium telluride nanocrystals in poly(3-hexylthiophene)ud

摘要

The present manuscript demonstrates the hole transport mechanism in an organic/inorganic hybridudsystem based on in-situ grown cadmium telluride (CdTe) nanocrystals in a poly(3-hexylthiophene)ud(P3HT) matrix. The increase of hole current in the hybrid system is correlated with the formation ofuda host-guest (P3HT-CdTe) charge transfer complex duly supported by photoluminescenceudquenching. The hole transport mechanism in P3HT is governed by a space charge limited currentudwith temperature, carrier density, and field dependent mobility. Incorporation of CdTe nanocrystalsudin a polymer matrix results in enhancement in the value of trap density Hb from 2.8 Â 1018 toud5.0 Â 1018 cmÀ3 and reduction in activation energies from 52 meV to 11 meV. At high trap density,udtrap potential wells start overlapping; this results in decrease of activation energies.ud