Hierarchical Uniform Crystalline Nanowires of Wide Bandgap Conjugated Polymer for Light-Emitting Optoelectronic Devices

The realization of robust luminescence in crystalline and anisotropic nanowires of wide bandgap light-emitting conjugated polymers (LCPs) is challenging. Compared to the periodic arrangements in conventional crystalline nanostructure, hierarchical uniform structures will provide an electronic landscape to obtain excellent optoelectronic behaviors, which are desirable for polymer light-emitting diodes (PLEDs) and polymer lasers. Here, we construct a range of robust hierarchical uniform crystalline nanowires of wide bandgap polydiarylfluorenes for light-emitting optoelectronic applications. Steric hindrance interactions of the bulky groups enable these nanowires to show a robust deep-blue emission, due to the suppression of interchain aggregation. Therefore, efficient deep-blue nanowire-based PLEDs with an intrachain excitonic behavior are fabricated. Moreover, our β-conformational hierarchical uniform nanowires present a low-threshold deep-blue lasing behavior. To the best of our knowledge, this is the first deep-blue organic nanolaser based on LCPs self-assembled nanowires by constructing hierarchical uniform crystalline structure.