Photoluminescent Anisotropy Amplification in Polymorphic Organic Nanocrystals by Light-Harvesting Energy Transfer

• Published in: Journal of the American Chemical Society Vol. 141; no. 15; pp. 6157 - 6161
• Main Authors: Sun, Meng-Jia, Liu, Yingying, Zeng, Wei, Zhao, Yong Sheng, Zhong, Yu-Wu, Yao, Jiannian
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 17.04.2019; Amer Chemical Soc
• Subjects: anisotropy; Chemistry; Chemistry, Multidisciplinary; energy transfer; nanocrystals; nanorods; photoluminescence; Physical Sciences; platinum; Science & Technology; EXCITON TRANSPORT; NANOFIBERS; STRATEGY; CRYSTALS; EMISSION; DERIVATIVES; PHOSPHORESCENT PLATINUM(II) COMPLEXES
• ISSN: 0002-7863; 1520-5126; 1520-5126
• DOI: 10.1021/jacs.9b02055

Polymorphism and anisotropy are fundamental phenomena of crystalline materials. However, the structure-dependent photoluminescent (PL) anisotropy in polymorphic organic crystals has remained unexplored. Herein, two polymorphic nanocrystals, green-emitting nanorods (PtD-g) and yellow-emitting nanoplates (PtD-y), were obtained from a platinum­(II)−β-diketonate complex. The PtD-y crystals display remarkable PL anisotropy with an anisotropy ratio of up to 0.87 whereas the emission of the PtD-g crystals is nearly unpolarized. The polarization properties are rationalized on the different molecular packing of these crystals. By light-harvesting energy transfer, the PtD-y crystals are successfully used to amplify the emission polarization of a red-emitting platinum acceptor (PtA) doped into the donor crystalline matrix, which is otherwise weakly polarized as pure crystals.