title: Effect of TiO2 nanoparticles on self-assembly behaviors and optical and photovoltaic properties of the P3HT-b-P2VP block copolymer.
abstract: An ordered nanostructure can be created from the hybrid materials of self-assembly poly(3-hexyl thiophene-b-2-vinyl pyridine) and nicotinic acid-modified titanium dioxide nanoparticles (P3HT-b-P2VP/TiO(2)). TEM and XRD analyses reveal that the TiO(2) nanoparticles (NPs) are preferentially confined in the P2VP domain of P3HT-b-P2VP whereas TiO(2) NPs interact with either pure P3HT or a blend of P3HT and P2VP to produce microsized phase segregation. The morphologies of lamellar and cylindrical structures are disturbed when the loading of TiO(2) NPs is 40 wt % or higher. Cylindrical P3HT-b-P2VP/TiO(2) exhibits a small blue shift in absorption and photoluminescence spectra with increasing TiO(2) loading as compared to P3HT/TiO(2). The NPs cause a slightly misaligned P3HT domain in the copolymer. Furthermore, the PL quenching of P3HT-b-P2VP/TiO(2) becomes very large as a result of efficient charge separation in the ordered nanodomain at 16 nm. Solar cells fabricated from self-assembly P3HT-b-P2VP/TiO(2) hybrid materials exhibit a >30 fold improvement in power conversion efficiency as compared to the corresponding 0.3P3HT-0.7P2VP/TiO(2) polymer blend hybrid. This study paves the way for the further development of high-efficiency polymer-inorganic nanoparticle hybrid solar cells using a self-assembled block copolymer.
authors.affiliation: Institute of Polymer Science and Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Wei-Che
authors.initials: WC
authors.lastname: Yen
authors.forename: Yi-Huan
authors.initials: YH
authors.lastname: Lee
authors.forename: Jhih-Fong
authors.initials: JF
authors.lastname: Lin
authors.forename: Chi-An
authors.initials: CA
authors.lastname: Dai
authors.forename: U-Ser
authors.initials: US
authors.lastname: Jeng
authors.forename: Wei-Fang
authors.initials: WF
authors.lastname: Su