title: Tuning optical properties of poly(3-hexylthiophene) nanoparticles through hydrothermal processing.
abstract: Poly(3-hexylthiophene) (P3HT) nanoparticles (NPs) were prepared by a reprecipitation method. Hydrothermal processing applied external pressure to the pristine P3HT NPs at temperatures ranging from 60 to 150 °C. Optical absorption and photoluminescence (PL) spectra for the hydrothermally treated P3HT NPs varied markedly with the processing temperature. With increasing treatment temperature, the absorption peak broadened and the peak position shifted from 510 to 623 nm; moreover, the intensity ratio of the 0-1 to 0-0 emission varied. These changes were caused by interactions between the P3HT main chains and alkyl side groups and conformational modifications induced by the high pressure during the hydrothermal process. The evolution of the optical absorption spectra of the P3HT NPs during the hydrothermal processing was strongly correlated with the variation of PL excitation spectra and with the PL emission spectra of a single NP.
authors.affiliation: Department of Physics, Korea University, Seoul 136-713, Korea.
authors.forename: Seok Ho
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Physics, Korea University, Seoul 136-713, Korea.
authors.forename: Yong Baek
authors.initials: YB
authors.lastname: Lee
authors.affiliation: Department of Physics, Korea University, Seoul 136-713, Korea.
authors.forename: Dong Hyuk
authors.initials: DH
authors.lastname: Park
authors.affiliation: Department of Physics, Korea University, Seoul 136-713, Korea.
authors.forename: Mi Suk
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Physics, Korea University, Seoul 136-713, Korea.
authors.forename: Eun Hei
authors.initials: EH
authors.lastname: Cho
authors.affiliation: Department of Physics, Korea University, Seoul 136-713, Korea.
authors.forename: Jinsoo
authors.initials: J
authors.lastname: Joo
keywords: hydrothermal process; interchain interaction; nanoparticles; optical absorption; photoluminescence; poly(3-hexylthiophene)