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 A2SnCl6 (A = K, Rb, and Cs) have attracted wide attention because of their unique optoelectronic properties and excellent stability. However, Sb3+-doped A2SnCl6 generally exhibits poor emission intensity. To overcome this, we take the all-inorganic A2SnCl6 as the conformational model and utilize a universal supramolecular assembly strategy to develop three different organic metal halides with dumbbell structures of (KC)2SnCl6:Sb3+, (RbC)2SnCl6:Sb3+, and (CsC)2SnCl6:Sb3+ (C = 18-crown-6). Compared with Sb3+-doped A2SnCl6 shows poor emission intensity, Sb3+-doped (AC)2SnCl6 exhibits the efficient tunable white emission with photoluminescence quantum yield (PLQY) of 86.7% for (KC)2SnCl6:Sb3+, 81.6% for (RbC)2SnCl6:Sb3+, and 89.8% for (CsC)2SnCl6:Sb3+, which stems from Sb3+-induce Jahn-Teller-like singlet and triplet self-trapped excitons (STEs) emission. Particularly, there eruptive PLQY obtained in Sb3+-doped (AC)2SnCl6 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)2SnCl6 facilitate the expression of Sb3+ 5s2 lone pairs. Moreover, Sb3+-doped (AC)2SnCl6 also has an excellent chemical- and photo-stabilities. Finally, taking Sb3+-doped (KC)2SnCl6 as an example, we further demonstrated its applications in single-compound white light-emitting diodes (WLED) at room temperature, multiple-mode optical anti-counterfeiting, and information encryption.