Recently, Prof. Wei Huang from Institute of Flexible Electronics of Northwestern Polytechnical University and Prof. Zhongfu An from Institute of Flexible Electronics of Northwestern Polytechnical University and Prof.Xiaogang Liu from National University of Singapore, have made a great breakthrough in the field of Organic Long Persistent Luminescence. The related results under the title“Colour-tunable ultra-long organic phosphorescence of a single-component molecular crystal”were published online on April 8 in the top international academic journal -- Nature Photonics .

Materials exhibiting long-lived, persistent luminescence in the visible spectrum are useful for applications in the display, information encryption and bioimaging sectors. Herein, the paper reported the development of several organic phosphors that provide colour-tunable, ultra-long organic phosphorescence (UOP). The emission colour can be tuned by varying the excitation wavelength, allowing dynamic colour tuning from the violet to the green part of the visible spectrum. Our experimental data reveal that these organic phosphors can have an ultra-long lifetime of 2.45 s and a maximum phosphorescence efficiency of 31.2%. Furthermore, the paper demonstrated the applications of colour-tunable UOP for use in a multicolour display and visual sensing of ultraviolet light in the range from 300 to 360 nm. The findings open the opportunity for the development of smart luminescent materials and sensors with dynamically controlled phosphorescence.