Finely Controlled Circularly Polarized Luminescence with Multimode Dynamic Response of Hybrid Metal Chlorides for Circularly Polarized White Light-Emitting Diode and Programmable Information Encryption

Stimulus-responsive materials that exhibit efficient circularly polarized luminescence (CPL) have gained much interest for application in advanced smart photonics. Herein, the CPL-active enantiomorphic 0D Sb 3+ -doped (R/S) 2 InCl 7 (R/S = R/S-2-methylpiperazine) are synthesized via a solution method. They show efficient broadband yellow emission with a near-unity photoluminescence quantum yield and a CPL asymmetry factor of 1.7 × 10 −3 . Their fascinating chiroptical activity should be attributed to the chirality transfer and self-trapped exciton emission caused by strong electron–phonon interaction. Particularly, H 2 O-induced structural transformation is demonstrated to obtain non-emission of Sb 3+ -doped (R/S) 2 InCl 7 ·H 2 O after exposure to a humid environment. Importantly, Sb 3+ -doped (R/S) 2 InCl 7 exhibits unique nonlinear optical responses, and the rotation angle between the quarter-wave plate and linearly polarized plate can regulate the reversible switching of Sb 3+ -doped (R/S) 2 InCl 7 between yellow emission and negligible luminescence. Moreover, a circularly polarized white light-emitting diode is fabricated by combining blue phosphors BaMgAl 10 O 17 :Eu 2+ , and the device exhibits tunable switching control of positive and warm white light by regulating the rotation angle of linear polarizer plate. Based on the tunable optical responses of Sb 3+ -doped (R/S) 2 InCl 7 , a programmable multi-mode fluorescence encoding system is constructed, and four-level information encryption and three-level encrypted 3D color codes are also realized in a further proof-of-concept experiment.