Hydrothermal synthesis of narrow-band red emitting K2NaAlF6:Mn4+phosphor for warm-white LED applications

The truncated octahedron shaped K₂NaAlF₆:Mn⁴⁺was preparedviahydrothermal route, which emits red light under blue light radiation. Warm WLEDs fabricated by the obtained red phosphor show lower color temperature and higher color rendering index.