Metallated conjugation in small-sized-molecular donors for solution-processed organic solar cells

摘要

Four metallated conjugated oligothiophenes,S-1,S-2,S-3 and S-4,with platinum(II)aryleneethynylenes as the electron-rich building block were synthesized to investigate their physicochemical and photovoltaic properties.These small molecules possess fairly low-lying HOMO energy levels which match with the LUMO energy level of the electron acceptor PC70BM([6,6]-phenyl-C71-butyric acid methyl ester).Using the simple process of spin-coating solution fabrication technique,S-1:PC70BM(1:4,w/w)based organic solar cells exhibiting a high Voc of 0.913 V,with a PCE value of 0.88%were developed.In contrast,the OSC device based on S-2:PC70BM(3:7,w/w)displayed a higher PCE of 1.59%with a higher Jsc value of 5.89m A cm–2.The device based on S-4:PC70BM(1:4,w/w)exhibited a PCE value of 1.56%,with a Voc of 0.917 V.