A Guanidinium-Based Mn4+-Doped Red-Emitting Hybrid Phosphor with High Stability

Great efforts have been put in search of phosphors to fulfill the requirements for phosphor-converted white lightemitting diodes (pc-WLEDs). Herein, a general organic-inorganic hybridization strategy was demonstrated in Mn4+-, Cr3+-, or Eu3+- doped guanidinium-based zero-dimensional hybrid fluorides to find phosphors for pc-WLEDs. Among which, GA(3)AlF(6):Mn4+ (where GA represents the guanidinium cation [C(NH2)(3)](2)) was selected to reveal their crystal structure, local symmetry, and luminescence properties. Density functional theory calculations suggested that GA(3)AlF(6) with a wide band gap (similar to 5.24 eV) and the F-1' interstitials are generated to balance the charge differences caused by non-equivalent doping. The GA(3)AlF(6) :Mn4+ hybrid could sustain similar to 573 K high temperature without degradation and keep 90.1% of the original luminescence intensity at similar to 373 K. A pc-WLED with wide color gamut (108.3%) of National Television System Committee standard was fabricated with GA(3)AlF(6):Mn4+, suggesting its potential in high-quality backlight displays. This work not only brings a brand-new kind of organic-inorganic fluoride phosphor family but also provides great guiding significance for future exploration of fluoride-based functional materials containing a hybrid structure.