Synthesis of surface-modified colloidal semiconductor nanocrystals and study of photoinduced charge separation and transport in nanocrystal-polymer composites

This paper provides an overview of semiconductor nanocrystals, which were synthesized either by an aqueous technique in the presence of different thiols as stabilizing agents (CdS, CdSe, CdTe, CdxHg1−xTe and HgTe) or via organometallic reactions (CdSe, CdTe, InP and InAs). In all cases, successful wide-range tuning of the semiconductor band-gap energies was achieved by the control of the nanocrystal size. In addition, the surface properties of the nanocrystals can be controlled by the exchange of the capping ligand. Blends of nanocrystals and conducting polymers, were prepared using CdTe nanocrystals and polyaniline, polypyrrole or poly(3,4-ethylenedioxythiophene) (PEDT), and considered with respect to possible optoelectronic applications. The photoinduced charge separation and transport in the CdTe–PEDT composites was investigated by photoelectrochemical methods.