Excitation-Dependent Tunable White Light of ns² Ions Doped Rb₂SnCI₆ Vacancy Ordered Double Perovskite

Single-matrix white light-emitting diodes are still a challenge. Achieving tunable white light emission from lead-free perovskites attracts much attention. Herein, nanoscale Rb2SnCl6 (RSC) vacancy ordered double perovskite were synthesized by an optimized precipitation method. Further, using ns(2) ions (Bi3+, Te4+, and Sb-3(+)) doped RSC vacancy ordered double perovskite to obtain broadband blue, yellow-green, and orange-red emission. The color temperature adjustable high-quality white light emission based on the codoping strategy is obtained by controlling the doping ratio of Bi3+ and Te4+. Additionally, the white light-emitting diodes encapsulated by this single matrix white luminescent material exhibit excellent stability. Combined with theoretical calculations, it is elucidated that these high-efficiency emissions are not only derived from the unique electronic transition of ns(2) ions but also related to the energy band properties and the crystal field. This work shows that ns(2) ions doped RSC vacancy ordered double perovskite can meet the needs of different luminous colors and color temperature tunable white light emission. Meanwhile, it is a strong competitor to replace the lead-based perovskite.