Effect of textured electrodes with light-trapping on performance of polymer solar cells

Abstract

Textured electrodes with rough surface in combination with reflective back contacts provide efficient light-trapping by light scattering and multiple reflections to increase the path length of the light, and the resulting enhanced efficiency of organic photovolatics. In this paper, the effect of textured electrodes with different surface morphology on the performance of polymer solar cells was investigated. Two kinds of textured SnO2:F (FTO) electrodes possessing “V” (V-FTO) and “U” (U-FTO) topography, respectively, were used as the front electrodes of polymer solar cells. Due to the enhanced light absorption in active layer, the resultant cells with U-FTO and V-FTO showed 9% and 6% improvement in short current density (Jsc), respectively, compared with the flat FTO electrode. The U-FTO electrode was amenable to coating a conformal buffer layer and preferred to obtain high efficient cells. However, the enhanced Jsc of the V-FTO cells did not contribute to the improved efficiency for the decreased fill factor and open circuit voltage.