Structure and photoluminescence studies of Rb3GdSi2O7: Eu2+ phosphor used for NUV converted white LEDs

In pursuit of healthy lighting, the exploitation of high-quality Eu 2+ -activated phosphors available for near-ultraviolet light-emitting diode (NUV-LED) chip-based white LED (WLED) has fetched growing interest. Herein, a novel NUV-light excitable Rb 3 GdSi 2 O 7 : Eu 2+ phosphor is successfully synthesized via a high-temperature solid-state reaction method. The crystal structure of Rb 3 GdSi 2 O 7 is found to be hexagonal, belonging to space group P6 3 /mmc. The Rb 3 GdSi 2 O 7 : Eu 2+ phosphor exhibits a broad excitation band in the 300–450 nm wavelength range, and it emits strong yellow-green light with peak at 543 nm upon 365 nm excitation. Benefitting from the high structure rigidity of host matrix, Rb 3 GdSi 2 O 7 : Eu 2+ also possesses a desired luminescence thermal stability (423 K, 85.6%). The WLED device fabricated using a 365 nm chip and a blend of the as-prepared Rb 3 GdSi 2 O 7 : Eu 2+ yellow-green phosphor and commercial BaMgAl 10 O 17 : Eu 2+ blue phosphor displays an excellent color-rendering index of 95.9 at a low correlated color temperature of 4373 K. This work confirms the applicative potential of Rb 3 GdSi 2 O 7 : Eu 2+ in NUV-converted warm WLEDs, which may promote the development of high-color-quality healthy lighting.