Enhanced photoelectrical conductivity of poly (3-hexylthiophene) by incorporation of ZnS nanoparticles

This paper reports an enhanced photoconduction behaviour of organic (poly 3-hexylthiophene)–inorganic (zinc sulphide) hybrid system. Poly (3-hexylthiophene) (P3HT) and ZnS nanoparticles have been synthesized by chemical route at 0 °C and 80 °C, respectively. The separately prepared organic–inorganic materials were blended in a nanohybrid system and coated over to ITO electrodes to forms different samples with different concentrations (5–15 wt%) of ZnS nanoparticles. The UV–visible spectra of these hybrid materials show an increase in the FWHM with ZnS nanoparticles, attributing to the enhanced optical properties. The photoconduction behaviour of the prepared samples has been investigated through current–voltage (I–V) measurements carried out under dark and light with fixed intensity (∼4.0 W/m2) of tungsten lamp. It is observed that photocurrent increases with ZnS concentration. Also, quenching has been observed for the samples having higher concentration of ZnS nanoparticles, in P3HT matrix. The temperature dependence of electrical current in dark and light shows that the decrease in the resistivity with the temperature is more pronounced in the presence of light, indicating a photon activated process.