Mn and Cu codoped CsZnBrmetal halide with multiexcitonic emission toward anti-counterfeiting.

The growing demand for optical anti-counterfeiting technology requires the development of new environmentally-friendly smart materials with single-component, multimodal fluorescence. Herein, CsZnBr:0.3Mn&0.15Cu, as an efficient multimodal luminescent material with excitation-wavelength-dependent emission is reported. Under 365 nm and 254 nm UV light excitation, CsZnBr:Mn&Cuemits mutually independent green light at 525 nm and blue light at 470 nm, which origin from the emission of Mnand the Cuenhanced self-trapped excitons of CsZnBr, respectively. Furthermore, the multiexcitonic emission is applied to anti-counterfeiting applications and information encryption and decryption engineering. This codoped strategy provides a colorful step to expand the new metal halide materials in fluorescent anti-counterfeiting and information encryption and decryption.