Enhanced Photovoltaic properties of P3HT/Cr-TiO2 bilayer film heterojunction solar cells

The simple bilayer solar. cells, composed of poly (3-hexylthiophene-2,5-diyl) (P3HT) and chromium doped titanium dioxide (Cr-TiO2) nanocrystal films, were fabricated by sal-gel method. The performances of structurally identical polymer-inorganic heterojunction solar cells Cu/Cr-TiO2/P3HT/FTO/Glass with various Cr3+ doping concentration were systematically investigated and compared. The results indicate that the samples' open-circuit voltage is remarkably enhanced from 0.42 V to 0.99 V, and short-circuit photocurrent increases at first and then reduces, with the increase of Cr3+ doping concentration. The enhancement mechanism of photovoltaic properties is discussed in detail. (C) 2013 Elsevier Ltd. All rights reserved.