Morphological modulation of optoelectronic properties of organic–inorganic nanohybrids prepared with a one-step co-fed chemical vapor deposition polymerization process

Abstract

A co-fed chemical vapor deposition polymerization (CVDP) process was developed to successfully prepare poly(p-phenylene vinylene)–CdS (PPV–CdS) nanohybrids in one step. The PPV and CdS were formed from the corresponding precursors, di-chloro-p-xylene and cadmium dipropyldithiocarbamate, respectively. The morphology of the nanohybrids can be readily tuned, from nanocomposites containing well dispersed nanocrystals to continuous bulk heterostructures, by controlling the precursor temperature and carrier gas flow rate, from which the optoelectronic properties of the nanohybrids can be effectively modulated. The p–n junctions formed by the p-type PPV and n-type CdS within the nanohybrids enhanced charge separation, giving rise to a one order of magnitude reduction in photoluminescence (PL) quantum yields and enhancement of current densities. The PL emissions first red-shifted and then blue-shifted back with increasing CdS loading, caused by the competition between the polarization and conjugation length reduction effects. The present work demonstrates a new way of designing organic–inorganic nanohybrids for applications requiring specific optoelectronic properties.