Electrical and Gas Sensing Behaviour of Polypyrrole/silver Sulphide Nanocomposites

Abstract

We investigated the room temperature NH3 sensing performance of polypyrrole/silver sulphide (PPy/Ag2S) nanocomposites (NCs). Sonochemically synthesized Ag2S nanoparticles (80-100 nm) were incorporated into the PPy matrix via ultrasound-assisted in-situ polymerization. The resulting PPy/Ag2S NCs were evaluated based on structural, morphological, and electrical properties. Microscopy results revealed a uniform dispersion of Ag2S nanoparticles in the PPy matrix. We studied the effect of Ag2S nanoparticle concentration on the electrical properties and gas sensing performance of the PPy/Ag2S NCs. The current-voltage (I-V) characteristics revealed the semiconducting nature of the PPy/Ag2S NCs. An improvement in the electrical conductivity was observed for the PPy/Ag2S NC with 3 wt% Ag2S nanoparticle content. PPy/Ag2S NCs were further tested for detection of NH3 in ambient conditions. The PPy/Ag2S NCs exhibited excellent sensor response towards 100 ppm NH3 concentration at room temperature.