Slow Energy Transfer in Self-Doped β-Conformation Film of Steric Polydiarylfluorenes toward Stable Dual Deep-Blue Amplified Spontaneous Emission

M.X. and L.S. contributed equally to this work. The work was supported by the National Natural Science Foundation of China (22075136, 61874053), National Key Research and Development Program of China (2020YFA0709900), Natural Science Funds of the Education Committee of Jiangsu Province (18KJA430009), Natural Science Foundation of Jiangsu Province (BK20200700), “High-Level Talents in Six Industries” of Jiangsu Province (XYDXX-019), Research Innovation in University of Jiangsu Province (KYCX21_0771), the open research fund from State Key Laboratory of Supramolecular Structure, Materials (sklssm202108) and Anhui Province Key Laboratory of Environment-friendly Polymer Materials and and Anhui Province Key Laboratory of Optoelectronic Materials Science and Technology. N.C. received support from an EPSRC Doctoral Training Studentship at the Centre for Plastic Electronics at Imperial College London.