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

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 non- localized 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|MEH- PPV|I2, under AM 1.5 conditions. Incident light to power conversion efficiency of these cells is about 0.6 %.