Wide-bandgap organic photovoltaics on flexible plastic substrates using conducting polymer electrodes

摘要

Single heterojunction and multi-heterojunction, small-molecule organic photovoltaic devices (OPVs) have been prepared on Glass/ITO and fully-flexible thermoplastic substrates using pre-patterned, conducting polymer electrodes (～450Ω/□). OPVs were fabricated via sequential vacuum vapor deposition of layers of the organic electron donating/hole transporting material: N,N'-(α-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine (a-NPD) and the electron accepting/transporting material C_(60). Devices built on glass/ITO substrates operated with a maximum, white-light power conversion efficiency (η_(power)) of 1.1% (AM1.5, 97 mW/cm~2). Analogous devices fabricated on fully-flexible, plastic substrates using conducting polymer transparent electrodes exhibited white-light power conversion efficiencies of ～1%, virtually identical to those fabricated on prepatterned ITO/glass substrates. The glass/ITO cells were further optimized by including an exciton blocking layer of 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and their η_(powerS) exhibited a 30% increase to 1.3%.