Herein, a new red phosphor Na 3GaF 6:Mn 4+ has been designed and synthesized by a facile two-step co-precipitation method at room temperature.
Herein, a new red phosphor Na 3GaF 6:Mn 4+ has been designed and synthesized by a facile two-step co-precipitation method at room temperature. Single crystal X-ray diffraction analysis reveals that the fluoride Na 3GaF 6 crystallizes in the P2(1)/ n space group with a = 5.4760 Å, b = 5.6862 Å, c = 7.9009 Å, β = 90.309°, and z = 2. Upon blue or UV light excitation, the obtained phosphor Na 3GaF 6:Mn 4+ emits intense and pure red fluorescence. The effects of raw materials, doping concentration and environmental temperature on its luminescence properties and crystal structure have been investigated and discussed in detail. Such a newly synthesized red phosphor shows excellent anti-thermal quenching behavior (∼118.8% of emission intensity at 150 °C relative to 25 °C) and good color stability upon blue light (∼467 nm) excitation. By using the Na 3GaF 6:Mn 4+ phosphor as a red light component, a high-power stable warm white light-emitting diode (WLED, R a = 81, CCT = 2966 K, luminous efficacy = 56.73 lm W −1) was fabricated, further evidencing the potential of the as-synthesized Na 3GaF 6:Mn 4+ phosphor for white LED applications.