Three novel Mn2+-based halides: Heat/acid-induced structural transformation and luminescent conversion

Mn2+-based halides show great promise for solid-state lighting and display applications owing to their structural flexibility and excellent luminescence properties. Herein, three hybrid manganese halides (N-AEP)[MnBr3(H2O)3]2·Br (1), [(N-AEP)2MnBr6]·2Br (2) and [(N-AEP)2MnBr4]·3Br(H2O) (3) with the same organic ligand have been successfully synthesized by adjusting various HBr level or temperature of growth solutions. Systematic characterizations of halides including crystal structure, thermal and photophysical properties were carried out. Their distinct inorganic groups lead to the various luminescence colors: purple-red light in 1, orange-red light in 2 and green light in 3. Some interesting physicochemical features, for 1 the temperature-dependent emission properties, 2 the satisfactory thermostability with higher PLQY (13.36%), and 3 the weak ferromagnetic coupling effect, broaden their application prospects. This paper offers sufficient synthetic experiences for Mn2+-based halides with different inorganic groups in detail, and provides a reasonable research scheme for their optical properties.