Organic single crystals have highest purity and long-range molecular packing, exhibiting better electronic performances. The exciton diffusion length is much longer than that of their amouphous ones. From this point of view, we prepared donor-acceptor single-crystalline heterojunctions from a single-step solution method and obvious photovoltaic behavior was recorded.

 H. Y. Li, C. C. Fan, W. F. Fu, H. L. Xin, H. Z. Chen, Angew Chem. Int. Edn. 2015, 54, 956-960.