Heterovalent Doping in CsCdCl3 Enabled Tunable Multimode Luminescence and Photochromism Toward Multilevel Anti-Counterfeiting

Authors：Zhou, Xinquan; Zhang, Shuai; Han, Kai; Jin, Jiance; Sun, Yongsheng; Xia, Zhiguo^*

Source：Advanced Optical Materials, 2023.

DOI：10.1002/adom.202302429

• defect levels
• multimode luminescence
• photochromism
• self-trapped excitons
• trap

Integrating self-trapped excitons (STEs), dopants, and defect levels in a single-component metal halide perovskite will be of significance for tunable multimode luminescence and photochromism. Here, a platform utilizing interactions of STEs, defects, and alien dopants in CsCdCl3 by a heterovalent doping strategy is demonstrated, in which the photoluminescence quantum efficiency is improved, and more importantly, the emissions can be manipulated statically and dynamically by dopants and changing excitation wavelength/irradiation time. Meanwhile, the presence of carrier trapping and de-trapping processes leads to bright orange-near-infrared persistent luminescence and photochromic behaviors, which can be quickly erased by white light, enabling visual displays and codable in dark and bright dual-fields. Inspired by these versatile optical characteristics of doped luminescent metal halides, a multilevel encryption and anti-counterfeiting platform with the advantages of nondestructive and convenient authentication is constructed.