Inverted Polymer Solar Cells with Reduced Interface Recombination

Abstract

Conjugated polymer solar cells are attractive as a source of renewable energy due to their compatibility with low cost rollto- roll printing processes. [ 1 ] The most effi cient of these polymer cells utilize a bulk heterojunction (BHJ) morphology, most often fabricated by blending a light-absorbing, electron-donating, and hole-transporting polymer with an electron-accepting fullerene derivative to form an active layer, which separates and transports charge carriers to the electrodes. While conventional BHJ cells are fabricated with a top cathode which requires a low work function metal for effi cient electron extraction, [ 2-5 ] this device architecture is not viable for large area processi..