Investigation of Acceptor Layer in Inverted Organic Multifunction Diodes

Organic multifunction diodes with light-emitting, photovoltaic, and photo sensing functions were demonstrated using a stack of N, N’-ditridecylperylene-3,4,9,10-tetracarboxylic diimide and 2,7-di(9H-fluoren-2-yl)benzo[lmn][3,8]-phenanthroline-1,3,6,8(2H,7H)-tetraone as an electron transporter/acceptor and rubrene as an emitter/donor. Polyethylenimine ethoxylated as an electron injection layer was introduced in an inverted-structured device. By using the inverted structure and introducing HFl-NDI to reduce the absorption in the acceptor layer, an increase in the emission and an increase in the short-circuit current density in the organic solar cell were obtained.