Band engineered p-type RGO–CdS–PANI ternary nanocomposites for thermoelectric applications†
A ternary hybrid nanocomposite of RGO–CdS–polyaniline (PANI) is prepared by a simple two stage in situ method for its thermoelectric studies. For this purpose, CdS quantum dots were first prepared with varying concentrations in the presence of reduced graphene oxide to form RGO–CdS nanocomposites using 3-mercaptopropionic acid as a linker. Polyaniline was then prepared in situ in the presence of RGO–CdS nanocomposites to eventually obtain RGO–CdS–PANI nanocomposites. The electrical conductivity, Seebeck coefficient and power factor of the RGO–CdS–PANI nanocomposites were calculated with various loadings of RGO–CdS nanocomposites in PANI. The final RGO–CdS–PANI nanocomposites delivered a high electric conductivity in the order of 105 S m−1 and showed strong re-dispersion in DMF and ethanol. The effective band alignment and decreased thermal conductivity in RGO–CdS–PANI nanocomposites resulted in p-type behaviour and a high power factor value.