Effect of Processing Parameters on Polymerization of P3HT in Presence of CdS

To achieve better incorporation and distribution of CdS nanoparticles in poly(3-hexylthiophene-2,5-diyl) (P3HT), the in situ methodology for synthesis of P3HT in presence of cadmium sulfide (CdS) was modified. P3HT/CdS composites were synthesized by in situ oxidative polymerization of 3-hexylthiophene monomer in presence of CdS using a 3-hexylthiophene (3HT)/CdS weight ratio of 1/0.21. CdS nanoparticles were added to the monomer solution instead of to the oxidant solution. The products were washed by centrifugation using different methods: (a) with methanol, hydrochloric acid, acetone, ammonium hydroxide, ethylenediaminetetraacetic acid, and distilled water, (b) with all solvents previously mentioned, except hydrochloric acid, and (c) with methanol and acetonitrile. The results revealed a greater incorporation and better distribution of CdS nanoparticles within the P3HT matrix when the synthesis process was modified. The presence of CdS in the P3HT polymer matrix improved the energy conversion efficiency by more than twofold when employing a glass/indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS)/P3HT-CdS:[6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM)/poly[(9,9-bis(3′-( N , N -dimethylamino)- propyl)-2,7-fluorene)- alt -2,7-(9,9-dioctylfluorene)] (PFN)/Field’s metal (FM) device architecture.