Surfactant-treated graphene oxide in organic solvents and its application in photovoltaic cells

In this paper, a simple and non-poisonous “surfactant treatment” method to prepare graphene oxide (GO) in organic solvents with good dispersibility was presented. As the surfactant molecules, didodecyldimethyla-mmonium bromide (DDAB) was attached onto the GO sheets via ionic interactions by mild sonication, the obtained GO:DDAB nanocomposites were then blended into copolymer Poly(3-hexylthiophene-2,5-diyl) (P3HT) [6,6]:-Phenyl C61 butyric acid methyl ester (PC61BM) as the active layer to fabricate bulk-heterojunction (BHJ) organic solar cells ITO/PEDOT:PSS/P3HT:PC61BM:(GO:DDAB)/Ca/Al. The concentration of GO:DDAB in the active layer, a maximum power conversion efficiency (PCE) of 3.67% was obtained by blending 0.5 mg/mL GO:DDAB in the active layer, showing an efficiency increment of 13.35% as compared with that of the control device without doping GO:DDAB. The optimized OPVs with PTB7:PC71BM by adding GO:DDAB shows the PCE of 7.96%. Therefore, it paves a way to get high efficiency organic photovoltaic cells by directly blending surfactant-treated graphene oxide in organic solvent. •“Surfactant treatment” method to prepare GO in organic solvents is presented.•DDAB was attached onto the GO sheets via ionic interactions by mild sonication.•A PCE of 3.67% was obtained by doping 0.5 mg/mL GO:DDAB in P3HT:PC61BM.•A PCE of 7.96% was obtained by doping GO:DDAB in PTB7:PC71BM.•Surfactant-treated GO in organic solvent paves a way for high-efficiency OSC.