Polymer Photovoltaic Cells Based on Blend of MEHPPV:C_(60) Derivatives

摘要

Photoinduced electron transfer from conjugated polymer poly(2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) to C_(60) has been reported [1,2]. In blends made with such two components, microscopic phase separation occurs at the donor (MEHPPV) and the acceptor (C_(60)) interface and interpenetrating bi-continuous network (IPN) forms in the blend films [3]. Such polymer films can be used in fabricating high energy conversion efficiency (ECE) polymer photovoltaic cells [3]. In this paper we study the effect of structure modification of C_(60) derivatives on the performance of PV cells. A series of PCBM (1-(3-(methoxycarbonyl)propyl)-1-phenyl[6,6]C61), derivatives with different alkyl chain length (C1-C16) were synthesized. Their molecular structures are shown in Fig. 1. We fabricated photovoltaic cells with structure of ITO/PEDOT (70nm)/doped MEH-PPV blend(100nm)/Ba/Al, where dopant for MEH-PPV is PCBM derivatives.