Single‐Component 0D Metal–Organic Halides with Color‐Variable Long‐Afterglow toward Multi‐Level Information Security and White‐Light LED

Abstract The optical anti‐counterfeiting science and technology are currently restricted by the limited information loading capacity, and thus development of multi‐level and high‐security systems is urgently needed but still challenging. Herein, anti‐counterfeiting design strategies (including ASCII/5D codes and dynamic information storage) are reported by incorporation of abundant multi‐central luminescence and time‐resolved, excitation‐dependent ultralong phosphorescence. Self‐assembly of new single‐component 0D organic–inorganic metal halides (OIMHs) are facilely achieved, which exhibit divisible ultralong all‐phosphorescence, thermally activated delayed fluorescence, and single‐molecule white‐light emission, as proved by experiments and theoretical calculations. Interestingly, combing advantages of both inorganic cluster and π‐conjugation in OIMHs, the time‐dependent afterglow affords color‐variable emission in a wide wavelength range larger than 100 nm, providing extra color‐time dimensions for information encryption compared to traditional single‐color fluorescent anti‐counterfeiting. Moreover, white light‐emitting diode device is further developed to show high lighting ability for the single‐component OIMH. Therefore, this study paves an effective way to fabricate cluster‐based single‐component hybrids by equipping different emitters to confer diverse photoluminescence manners and satisfy down‐to‐earth application requirements.