Improvement of the performance of inverted polymer solar cells with a fluorine-doped tin oxide electrode

► Inverted polymer solar cells on FTO electrode with various buffer and SAM layers. ► TiO2, WO3, and WOx films were used as selective charge transport layers. ► WOx film is good for low cost, easy fabrication and large area solar cells. ► The self-assembled molecular layer of PCBA and N719 on top of TiO2 improves the PCE.