Large [6,6]-phenyl C61 butyric acid methyl (PCBM) hexagonal crystals grown by solvent-vapor annealing

We propose that solvent-vapor annealing is an efficient method for fabricating large [6,6]-phenyl C-61 butyric acid methyl (PCBM) single crystals. The morphology and size of PCBM crystals are influenced by different substrates and annealing solvents. Hexagonal PCBM crystals > 150 mu m in size were obtained when crystallization was performed on bare SiO2 substrate under the saturated vapor of chloroform for annealing. The proposed method was also applied to a bi-component system, which led to the spontaneous formation of PCBM and dioctylbenzothienobenzothiophene single crystals. (C) 2014 Elsevier B.V. All rights reserved.