Antwi, B.Y.Taylor, R.G.D.Cameron, J.Owoare, R.B.Kingsford-Adaboh, R.Skabara, P.J.2019-04-292019-04-29201620462069doi.10.1039/c6ra22897fvol.6,101http://ugspace.ug.edu.gh/handle/123456789/29650Three simple semiconducting acceptor-donor-acceptor (A-D-A) small molecules based on an electron-rich (3,4-ethylenedioxythiophene) EDOT central core have been synthesised (DIN-2TE, DRH-2TE, DECA-2TE) and characterised. Organic photovoltaic (OPV) devices incorporating these materials have been prepared and evaluated. The physical properties of the molecules were characterised by TGA, DSC, UV/vis spectroscopy and cyclic voltammetry. The optical HOMO-LUMO energy gaps of the molecules in the solid state were in the range 1.57-1.82 eV, and in solution 1.88-2.04 eV. Electrochemical HOMO-LUMO energy gaps determined by cyclic voltammetry were found to be in the range 1.97-2.31 eV. The addition of 1% 1,8-diiodooctane (DIO) to photoactive blends of the A-D-A molecules and PC71BM more than doubled the power conversion efficiency (PCE) in the case of DRH-2TE:PC71BM devices to 1.36%. © 2016 The Royal Society of Chemistry.enArticle