A universal supramolecular assembly strategy for achieving efficient tunable white emission and anti-counterfeiting in antimony doped tin(IV)-based vacancy-ordered double perovskites

Recently, Sb3+-doped all-inorganic vacancy-ordered double perovskites A(2)SnCl(6) (A = K, Rb, and Cs) have attracted wide attention because of their unique optoelectronic properties and excellent stability. However, Sb3+-doped A(2)SnCl(6) generally exhibits poor emission intensity. To overcome this, we take all-inorganic A(2)SnCl(6) as the conformational model and utilize a universal supramolecular assembly strategy to develop three different halide perovskite materials with dumbbell structures of (KC)(2)SnCl6:Sb3+, (RbC)(2)SnCl6:Sb3+, and (CsC)(2)SnCl6:Sb3+ (C = 18-crown-6). While Sb3+-doped A(2)SnCl(6) shows poor emission intensity, Sb3+-doped (AC)(2)SnCl6 exhibits efficient tunable white emission with a photoluminescence quantum yield (PLQY) of 86.7% for (KC)(2)SnCl6:Sb3+, 81.6% for (RbC)(2)SnCl6:Sb3+, and 89.8% for (CsC)(2)SnCl6:Sb3+, which stems from Sb3+-induced Jahn-Teller-like singlet and triplet self-trapped exciton (STE) emission. Particularly, the eruptive PLQY obtained in Sb3+-doped (AC)(2)SnCl6 can be attributed to the strong supramolecular interactions increasing the structural rigidity and thus inhibiting non-radiative transitions. Longer Sb-Sb distances in Sb3+-doped (AC)(2)SnCl6 facilitate the expression of Sb3+ 5s(2) lone pairs. Moreover, Sb3+-doped (AC)(2)SnCl6 also exhibits excellent chemical- and photo-stabilities. Finally, taking Sb3+-doped (KC)(2)SnCl6 as an example, we further demonstrated its applications in single-component white light-emitting diodes (WLEDs) at room temperature (RT), multiple-mode optical anti-counterfeiting, and information encryption.