Small molecules based difluoroquinoxaline for organic solar cells

A new accepter unit, 2,3-didodecyl-6,7-difluoroquinoxaline, was prepared and utilized for the synthesis of electron acceptor–donor–acceptor materials for organic solar cells. 2,3-Didodecyl-6,7-difluoroquinoxaline unit was designed to introduce electron-withdrawing F atom in quinoxaline unit to improve deeper HOMO energy levels and higher VOC of the materials. The thienothiophene in conjugated materials has more excellent electron-donating ability to decrease of HOMO energy levels, which improves efficiency by increasing the VOC values.