Effects of Hole and Electron Transporting Interlayers for Inverted Polymer Solar Cells

Abstract

An efficient inverted polymer solar cell (PSC) with a transparent amorphous titanium oxide (TiOx) as an electron transporting layer (ETL) between bottom electrode and photo-active layer, and a tungsten oxide (WO3) inserted as a hole transporting layer (HTL) was fabricated. Introducing of ETL and HTL results in increases in the open circuit voltage (V-oc), short circuit current (J(sc)) and the fill factor (FF). The inverted PSC device with TiOx and WO3 layer showed the higher power conversion efficiency (PCE) than that of conventional PSC. The PCE of 3.73% was achieved at inverted device, and was retained over 87% of its initial efficiency after 25 days in the ambient air without encapsulation.