SnO2 interlayer effects on the inverted polymer solar cells

Abstract By inserting a tin oxide (SnO2) thin film layer in between Fluorine-doped Tin Oxide (FTO) and titanium dioxide (TiO2) electron-selective layers, the performance of P3HT: PCBM based bulk-heterojunction type inverted polymer solar cells is considerably enhanced. A device with adding SnO2 layer showed a significant increase in PCE of 2.87% with an improved short-circuit current from 6.8 mA/cm2 to 10.40 mA/cm2, compared to a reference device without SnO2 layer (2.18%). The relative increase in PCE value was 31.7%. Such enhancement is assigned to the excellent optical transparency and high electrical conductivity of the wide-band gap of SnO2 thin film layer.