Multi-Mode Photoluminescence Regulation in a Zero-Dimensional Organic-Inorganic Hybrid Metal Halide...

Metal ion-doped zero-dimensional halide perovskites provide good platforms to generate broadband emission and explore the fundamental dynamics of emission regulations. Recently, Sb³⁺-doped zero-dimensional halide perovskites have attracted considerable attention for the high quantum yield of yellow emission; however, the triplet state recombination is activated and the singlet state emission is usually absent. Herein, we fabricate an Sb³⁺-doped zero-dimensional [(CH₃)₄N]₂SnCl₆ perovskite that can induce singlet and triplet emission. Density functional theory calculation shows that there are some overlaps between the highest occupied molecular orbitals and the lowest unoccupied molecular orbitals, which may induce a large energy separation between the lowest excited triplet states (T₁) and the lowest excited singlet states (S₁) [ΔE(S₁ - T₁)], impeding all the carriers' transfer from the singlet state to the triplet state. As a result, the reserved singlet emission together with the triplet emission can be regulated by excitation wavelength in situ. In addition, different Bi³⁺ ratios are co-doped into Sb³⁺@[(CH₃)₄N]₂SnCl₆, resulting in a photoluminescence ex situ regulation. Single-phase white light LED and optical anti-counterfeiting are developed further.