Synthesis of polypyrrole/zinc oxide composites and study of their structural, thermal and electrical properties

Intrinsically conducting PPy/ZnO composites were synthesized with varying amounts of zinc oxide (0–20 wt.%) via a facile chemical oxidation polymerization approach. These composites were characterized for their structure, thermal stability, surface morphology and DC electrical conductivity by XRD, FT-IR, TGA, DSC, SEM and four-probe method respectively. FT-IR results show broadening and shifts of peaks towards lower wave numbers in all composites suggesting better conjugation and some chemical interactions between PPy and ZnO particles. Powder X-ray diffraction analysis demonstrated the amorphous nature of PPy and its composites as well with no indication of crystalline peaks. The percolation threshold for conductivity of PPy/ZnO composites was 15 wt.% of the volume fraction of PPy. SEM and TGA data suggest that PPy/ZnO composites have high thermal stability due to better conformation, compactness and reduction of grain boundary volume with zinc oxide particle loading that in parallel enhanced their DC conductivity.