Analyzing morphological and optical properties of poly(3-hexylthiophene) (P3HT) via emitted light’s polarization

With the improvement in synthetic methodologies, polythiophenes and specifically poly(3-hexylthiophene) (P3HT) have become forerunners in the field of conjugated polymers. We study P3HT’s morphological and optical properties via measurements of absorption and polarization-resolved photoluminescence via Stokes spectroscopy. Our recent results show that P3HT’s aggregation behaviors change drastically when using chloroform stabilized and non-stabilized by amylene. Specifically, P3HT drop-cast films made from stabilized chloroform presented H-aggregates, while similar samples using non-stabilized chloroform exhibited J-aggregates. Here, we hypothesize that the amylene from stabilized chloroform induces a higher probability for the stacked coupling of isolated chains via weak van-der-Waals force leading to the formation of H-aggregates. To rule the influence of amylene out, we are currently performing a set of analyses and experiments consisting of temperature-dependent measurements, thermal annealing, various P3HT chain sizes, and blended MeOH@Chloroform solvents.