Combined alternative electrodes for semi-transparent and ITO-free small molecule organic solar cells

► Different electrodes for semi-transparent and ITO-free OPV cells are demonstrated. ► Free combination of bottom and top electrodes by using small molecules and doping. ► Thin Ag films, ITO, PEDOT:PSS, and Ag nanowires are employed as bottom electrodes. ► Thin Ag layers and free-standing carbon nanotube sheets are used as top electrodes. ► The combination of Ag nanowires and thin Ag top-layer is particularly efficient.