Methanofullerenes, C60(CH2)n (n = 1, 2, 3), as building blocks for high-performance acceptors used in organic solar cells

Org Lett. 2014 Jan 17;16(2):612-5. doi: 10.1021/ol4035275. Epub 2014 Jan 3.

Abstract

Selective preparation of C60(CH2)n (n = 1, 2, 3) was realized via a "Bingel-decarboxylation" route. A 54π-electron derivative of C60(CH2)2, OQBMF, demonstrates an outstanding power conversion efficiency (PCE) of 6.43% (Voc = 0.95 V, Jsc = 9.67 mA cm(-2), FF = 70%) in fullerene:P3HT solar cells since the small CH2 addends lift up fullerene LUMO and increase Voc significantly without decreasing mobility significantly.