Photoconductivity of CdS nanocluster-doped polymers

We report the first demonstration of photoconductivity of a polymer film doped with nanometer-sized semiconductor clusters (quantum dots). In such a composite, the semiconductor cluster acts as a sensitizer for the photogeneration of carriers and the polymer serves as the carrier-transporting medium. In this study we have measured the wavelength and field dependence of the charge generation efficiency of a polyvinylcarbazole film doped with ≈ 16 Å CdS clusters and discussed the mechanism for photoconduction. We believe this approach may be extended to include many other semiconductor nanoclusters to create a novel class of photoconductive material.