Polypyrrole/Metal Sulphide Hybrid Nanocomposites: Synthesis, Characterization and Room Temperature Gas Sensing Properties

Abstract

Abstract The present research work explores the room temperature gas sensing ability of hybrid nanocomposites of metal sulphide nanoparticles with polypyrrole (PPy) matrix. Sonochemically synthesized both silver sulphide (Ag2S) and cadmium sulphide (CdS) nanoparticles were mixed in varying ratios with PPy matrix by in-situ oxidative polymerization route. The resulting PPy/(Ag2S:CdS) hybrid nanocomposites were analyzed by characterizing them using FTIR and UV-Visible spectroscopy, XRD, SEM, four-probe conductivity method and gas sensing ability by two-probe gas sensing setup. The current-voltage (I-V) characteristics of the PPy hybrid nanocomposites revealed their semiconducting nature with an electrical conductivity in the range of 10−4 to 10−3 S/cm. As compared to pure PPy, their hybrid PPy/(Ag2S:CdS) nanocomposites showed an enhancement in sensitivity towards ammonia gas detection. The results clearly indicated a synergistic effect between the Ag2S:CdS nanoparticles and the PPy matrix.

Keywords

• Metal sulphide nanoparticles
• Hybrids
• Polypyrrole
• Gas sensing