Solar Energy, Vol.99, 126-133, 2014
Ternary MEH-PPV-CuInS2/ZnO solar cells with tunable CuInS2 content
The paper reports novel ternary MEH-PPV-CuInS2/ZnO solar cells fabricated by incorporating CuInS2 quantum dots (QDs) into pristine MEH-PPV as light-harvester and vertically aligned ZnO nanorod array as electron acceptor. Results show that, MEH-PPV-CuInS2/ZnO solar cells exhibit increased photovoltaic performance compared to MEH-PPV/ZnO devices and the performance dependent on the weight ratio (R) between CuInS2 and MEH-PPV, resulting in a peak power conversion efficiency of 2.48% for R = 0.6 at 15.85 mW/cm(2) monochromatic illumination. It is revealed that the increased J(sc) is due to the improved light-harvesting, additional MEH-PPV/CuInS2 interfaces for exciton dissociation, and the formation of CuInS2 channels for effective charge transport, while the increased V-oc and the decreased charge recombination are attributed to the modification of ZnO surface by CuInS2 QDs which reduces the surface defect concentration of ZnO. However, the decreased J(sc), V-oc, at too high R value are attributed to the serious aggregations of CuInS2 QDs resulting in the inorganic nanocrystals not well dispersed in organic matrix. (C) 2013 Elsevier Ltd. All rights reserved.