Organic Photovoltaic Cell with Donor-Acceptor Double Heterojunctions

Abstract

An organic photocell, which has a multilayer structure consisting of poly(2,5-dioctyloxy-p-phenylenvinylene) (OOPPV)/octaethylporphine (OEP)/backminsterfullerene (C₆₀), has been fabricated. The photocurrent yield spectra are measured in terms of the light absorption in the OEP layer, the exciton migration and the charge generation at both organic heterojunctions. That is, the double heterojunctions OOPPV/OEP and OEP/C₆₀ contribute to the charge generation by excitonic dissociation. The mechanisms of charge generation and photocurrent enhancement are discussed taking the energy band structure and photoinduced charge transfer into consideration.