School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Key Lab of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, Shanghai, 200240, China.
State Key Laboratory of Superhard Materials, Jilin University, Changchun, 130012, China.
Small. 2020 Dec;16(49):e2005035. doi: 10.1002/smll.202005035. Epub 2020 Nov 9.
The rational modulation of the nontraditional intrinsic luminescence (NTIL) of nonconventional luminophores remains difficult, on account of the limited understanding on the structure-property relationships and emission mechanisms. Herein, the effective modulation of NTIL is demonstrated based on a group of nonaromatic anhydrides and imides. Mutual bridging of isolated subgroups effectively promotes intramolecular through-space conjugation (TSC), leading to red-shifted emission, enhanced efficiency, and prolonged persistent room-temperature phosphorescence (p-RTP). The substitution of heteroatoms from oxygen to nitrogen drastically changes the TSC and enhances intermolecular interactions, resulting in enhanced emission efficiency. In addition, upon freezing, compression, or embedding into polymer matrices, the emission intensity and color remain well regulated. These results shed new light on the rational modulation of the NTIL and p-RTP of nonconventional luminophores.
非传统本征发光（NTIL）的非传统发光体的合理调制仍然很困难，这是由于对结构-性质关系和发光机制的理解有限。在此，基于一组非芳香酐和酰亚胺证明了 NTIL 的有效调制。孤立亚基的相互桥接有效地促进了分子内的通过空间共轭（TSC），导致发射红移、效率提高和延长室温磷光（p-RTP）。从氧到氮的杂原子取代从根本上改变了 TSC 并增强了分子间相互作用，从而提高了发射效率。此外，在冷冻、压缩或嵌入聚合物基质时，发光强度和颜色仍能得到很好的调节。这些结果为非传统发光体的 NTIL 和 p-RTP 的合理调制提供了新的思路。
