Optical properties of Poly-[2-methoxy-5-(2-ethyl-hexyloxy)-phenylene vinylene and its application in photovoltaic cells

Abstract

A conjugated polymer poly[2-methoxy-5-(2-ethyl-hexyloxy)-phenylene vinylene] (MEH-PPV) exhibits unique absorption band in the visible region due to electron transitions between nonlocalized bands and emits light in three different wavelength regions. Doping of iodine increases absorption in the visible region of polymer. MEH-PPV is used as a hole-conductor and a sensitizer in titana based solid-state photovoltaic cells. Maximum photocurrent of 1.3 mAcm -2 and voltage of about 543 mV are observed for a photovoltaic cell with the polymer sensitizing layer. However, slightly higher photocurrent (2.4 mAcm -2 ) with a decrement of voltage (465 mV) is observed for a solid-state cell with a configuration of TiO2|dye|MEHPPV|I2, under AM 1.5 conditions. Incident light to power conversion efficiency of these cells is about 0.6 %.