Enhanced Efficiency of Polymer: Fullerene Bulk Heterojunction Solar Cells with the Insertion of Thin TiO2 Layer near the LiF/Al Electrode
-
Abstract
The insertion layer of TiO2 between polymer-fullerene blend and LiF/Al electrode is used to enhance the short-circuit current I sc and fill factor (FF). The solar cell based on the blend of poly2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene (MEH-PPV) and C60 with the modifying layer of TiO2 (about 20nm) shows the open-circuit Voc of about 0.62V, short circuit current Isc of about 2.35mA/cm2, filling factor FF of about 0.284, and the power conversion efficiency (PCE) of about 2.4% under monochromatic light (500nm) photoexcitation of about 17mW/cm 2. Compared to cells without the TiO2
layer, the power conversion efficiency increases by about 17.5%. Similar effect is also obtained in cells with the undoped MEH-PPV structure of ITO/PEDOT:PASS/MEH-PPV/(TiO2)LiF/Al. The improved solar cell performance can be attributed to enhanced carrier extraction efficiency at the active layer/electrode interfaces when TiO2 is inserted.
Article Text
-
-
-
About This Article