Photovoltaic characteristics of TCNQ-incorporated CuPc-poly(p-phenylene) composite films

Composite films (CuPc-PPP-TCNQ) were produced by simultaneous deposition using copper phthalocyanine (CuPc) as a carrier generation material, poly(p-phenylene) (PPP) as a hole transport material, and tetracyanoquinodimethane (TCNQ) as a incorporation material. Schottky barrier photovoltaic cells, consisting of a semitransparent aluminum and the CuPc-PPP-TCNQ composite films, were fabricated. The junction properties and the photovoltaic properties on Al/CuPc-PPP-TCNQ/ITO sandwich cells were investigated. As well as a composite film of the CuPc and the PPP (CuPc-PPP), the conductivity of the CuPc-PPP-TCNQ composite film is improved as the TCNQ is simultaneously deposited in the CuPc-PPP composite film. Therefore, it is proven that the short circuit photocurrent density (J^sub sc^) and the photovoltaic property increases significantly. The J^sub sc^ of the Al/CuPc-PPP-TCNQ/ITO cell is 2.60 μA/cm^sup 2^, and it is found that the J^sub sc^ is about 20 times that of an Al/CuPc/ITO cell and double that of an Al/CuPc-PPP/ITO cell. Consequently, the power conversion efficiency of the Al/CuPc-PPP-TCNQ/ITO cell obtained was 3.68%.[PUBLICATION ABSTRACT]