Probing the real-time photocatalytic activity of CdS QDs sensitized conducting polymers: Featured PTh, PPy and PANI

In the present work, we first synthesized widely used conducting polymers like polythiophene (PTh), polypyrrole (PPy) and polyaniline (PANI) by oxidative coupling method. Later, we have in-situ grown cadmium sulfide (CdS) quantum dots (QDs) in presence of these conducting polymers to form CdS/polythiophene (CdS/PTh), CdS/polypyrrole (CdS/PPy) and CdS/polyaniline (CdS/PANI) hybrid nanocomposites. All characterization techniques confirm the formation of hybrid nanocomposites while also highlights the interaction of CdS with conducting polymers. Thereafter, as synthesized conducting polymers and their hybrid nanocomposites were employed as photocatalyst for degradation of methylene blue (MB) dye under direct sun light (light intensity = 75000-90000 Lux). Here, CdS plays a key role to enhance the photocatalytic activity of overall composite due to effective charge transfer with these conducting polymers. The in-depth comparative study of photocatalytic activity was performed for these hybrid nanocomposites and the effectiveness with respect to stability is reported. The role of CdS QDs as sensitizer is proposed on the basis of synergetic effect between CdS and PTh, PPy or PANI polymers.