Charge compensation engineering for high-performance dolomite-type BaTi(BO3)2:Eu3+ red-emitting phosphor for backlight display applications with a wide color gamut

Abstract

Exploiting high color purity phosphors is a core problem in the development of phosphor conversion light-emitting diodes (pc-LEDs) for display devices. Eu³⁺-activated BaTi(BO₃)₂ (BTB) red-emitting phosphors were first synthesized via a solid-state reaction at low temperature and alkali metal ions Na⁺ were co-doped in BTB:xEu³⁺ to improve the luminescence properties. The occupation of the Eu³⁺ ions and the enhancement principles of the Na⁺ ions and their effect on the photoluminescence properties of the BTB:xEu³⁺ phosphors are discussed in detail. The BTB:xEu³⁺,Na⁺ system demonstrated a strong thermal stability (68.4% at 150 °C), low color temperature (about 1940–1950 K) and high color purity (almost 90%). Furthermore, the prototype LED device can emit a bright white light, has a stable luminous efficiency and color rendering index, and the color gamut reaches 115.5% of the NTSC standard. Therefore, the BTB:xEu³⁺,Na⁺ series phosphors provide a better choice for the development of lighting and display devices with a wide color gamut.