Lead-Free Tin(IV)-Based Organic–Inorganic Metal Halide Hybrids with Excellent Stability and Blue-Broadband Emission

Lead-free zero-dimensional (0D) organic-inorganic metal halide hybrids have recently attracted special attention as luminescent materials. However, their structural stability is still a challenge for the further development. Here, we select Sn⁴⁺ as the B-site inorganic cation and obtain a new tin(IV)-based organic-inorganic metal halide hybrids (C₆N₂H₁₆Cl)₂SnCl₆ with remarkable air stability. (C₆N₂H₁₆Cl)₂SnCl₆ exhibits a blue broadband emission originating from self-trapping excitons (STEs) and the emission intensity remains stable for over three months. When the temperature rises to 450 K, the intensity of photoluminescence can maintain about 50%, indicating the good thermal stability of (C₆N₂H₁₆Cl)₂SnCl₆. This work presents a new strategy toward the tin(IV)-based photoluminescent organic-inorganic metal halide hybrids with environmentally friendly, high stability characteristics.