Synthesis, characterization and photovoltaic properties of novel molecules based on triarylamine dyes

We report the synthesis, electrochemical and photovoltaic properties of triphenylamine based novel organic sensitizer, comprising donor, electron-conducting and anchoring group. Different triphenylamines were synthesized as donor unit and connected to cyano-acidic acid acceptor over vinyl group. In this work, we studied on two novel dyes (TPA2, TPA3) by attaching methyl to m-position and diphenylamine to p-position of the basic triphenylamine structure, respectively. All derivatives absorb at visible region of solar spectrum in the range of 350-632 nm. By introducing strong electron injection groups to triphenylamine ring, band gap becomes narrower while E-HOMO-E-LUMO levels are tuned. All current voltage (I-V) measurements were done under 100 mW/cm(2) light intensity and AM 1.5 conditions. TPA3 chromophore with the lowest band gap shows the best cell performance with an efficiency (eta) of 4.12%, a short-circuit photocurrent density (I-sc) of 8.07 mA/cm(2), an open-circuit voltage (V-oc) of 714 mV and a fill factor (FF) of 0.72. (c) 2009 Elsevier B.V. All rights reserved.