The effect of molybdenum oxide interlayer on organic photovoltaic cells

Polymer solar cells (PSCs) have attracted increasing attention due to their inexpensive, flexible, light weight and large area device fabrication. However, the efficiency of PSCs is still not yet sufficient for large scale implementation. Many approaches have been proposed to enhance the efficiency of PSCs. In addition to using new materials and new device structure, the performance of polymer solar cells can also be improved using efficient interface layer between the electrode and active layer. Here, we studied the effect of MoO3 as an anode interlayer on both small molecule and polymer photovoltaic cells. Significant improvement has been observed in the performance of PSCs and the power conversion efficiency (PCE) of the cell with a MoO3 interlayer can be enhanced by ~15% comparing to the cells with a PEDOT:PSS interlayer. This improved device performance is attributed to the combined effect of efficient charge extraction and the reduction in series resistance of device.