Photovoltaic Cells with TiO2 Nanocrystals and Conjugated Polymer Composites

Various compositional photovoltaic cells based on the blend of poly(3-hexylthiophene) (P3HT) as donors and TiO2 nanocrystals as acceptors are fabricated and investigated. It is demonstrated that the blend ratio of P3HT and TiO2 nanocrystals could greatly influence the performance of the photovoltaic cells. The maximum of 0.411% in power conversion efficiency under AM 1.5, 100mW/cm2, and 44.4% of fill factor are obtained in the solar cell with the blend weight ratio 1:1 of P3HT and TiO2 nanocrystals. The function of nanocrystal composition is discussed in terms of the results of photoluminescence spectroscopy, atomic force microscopy, transmission electron microscopy, and charge transport I-V curve.