Abstract

A functionalized fulleropyrrolidine derivative of 4, 7-di (thiophen-2-yl)-2, 1, 3-benzothiadiazole (F-DTBT) was designed and synthesized by 1, 3-dipolar cycloaddition reaction. This thermally stable fullerene derivative exhibits an absorption peak at 425nm along with the characteristic peak of fullerene. This functionalized derivative shows deeper HOMO level, -6.16eV and higher LUMO level -3.6eV compared to C60PCBM. Bulk heterojunction solar cells were fabricated using F-DTBT as the acceptor and P3HT as the donor material. The preliminary result shows a power conversion of efficiency of 1.1% with a Voc of 0.61V, a Jsc of 6.1mAcm^-2 and a fill factor of 29%. This functionalized DTBT with fullerene could be a stronger acceptor moiety compared to PCBM and could be a promising candidate for organic photovoltaics

Keywords: Fullerene functionalization; Bulk heterojunction; Organic photovoltaics