Enhanced fluorescence and water stability of Zr4+ ion-doped Cs2SnCl6: 5 %Te phosphors for high-performance WLEDs

Recently, vacancy-ordered double perovskite phosphors have garnered significant attention due to their high quantum efficiency, elevated carrier mobility, and favorable fluorescence properties. Vacancy ordered double perovskite phosphors has poor fluorescence properties due to the high number of vacancies. The fluorescence characteristics and stability can be enhanced through strategic ion doping. This study synthesized Zr 4+ ion-doped Cs 2 SnCl 6 : 5 %Te using hydrochloric acid-assisted precipitation method. The inclusion of Zr 4+ ions in proper proportions facilitated Jahn-Teller structural distortion in Te 4+ , thereby enhancing the generation of bright yellow-green emission. The photoluminescence quantum yield (PLQY) achieved a peak of 70.9 % at a Zr 4+ ion doping level of 15 %. Furthermore, a water stability test was conducted on the phosphors. At 15 % doping with Zr ions, The Cs 2 Zr 0.15 Sn 0.8 Cl 6 : 5 %Te phosphors demonstrated a remarkable stability, which maintained 100 % of its initial fluorescence intensity after immersion in water for 14 h, proving the excellent stability of the phosphors against water exposure. A white light-emitting diode (WLED) with color coordinates of (0.3486, 0.364), a correlated color temperature of 4915 K, and a color-rendering index (Ra) of 86 was prepared using Cs 2 Zr 0.15 Sn 0.8 Cl 6 : 5 %Te phosphor. This development offers a novel and eco-friendly approach to solid state lighting.