Realizing Red Mechanoluminescence of ZnS: Mn<sup>2+</sup> Through Ferromagnetic Coupling
Hongzhen Liu, Yuantian Zheng, Shengqiang Liu, Jing Zhao, Zhen Song, Dengfeng Peng, Quanlin Liu
Abstract
Abstract Self‐recoverable mechanoluminescence (ML) is becoming a novel technology widely used in the fields of sensing, display, and artificial intelligence. The dominant ML material, ZnS: Mn 2+ , is reported to solely present a yellow emission color, which limits the applications of self‐recoverable ML materials to a large extent. Herein, an effective strategy to extend the ML emission range of ZnS: Mn 2+ by the ferromagnetic coupling of Mn 2+ ions are reported. Under the thermal carbon‐reduction atmosphere (TCRA), the emission ranges of ML, photoluminescence (PL), and persistent luminescence spectra of ZnS: Mn 2+ phosphors are all successfully broadened from yellow to red. Furthermore, as for the PL and ML intensities of ZnS: Mn 2+ , they are intensified to 1.76 and 3.23 folds larger under the TCRA treatment than those in pure nitrogen, respectively. Various spectra and magnetic test results reveal that the red emission bands of ZnS: Mn 2+ @TCRA phosphors originate from the ferromagnetic coupling of Mn 2+ ions. This study is the first to realize strong red emission and tunable multicolor luminescence in the conventional ZnS‐based phosphors, which introduces opportunities for discovering the multiband emissions of Mn 2+ ion in other compounds. Brightly multicolored ZnS: x Mn 2+ @TCRA elastic films have been fabricated to demonstrate their anti‐counterfeiting and security applications.