Cs 2 MnCl 4 :Eu 2+ : A Near-Violet Light-Triggered Single-Component White Light Emitter.

Single-component white-light luminescent materials are considered an economical and facile choice for phosphor-converted white light-emitting diodes (pc-WLEDs). Here, a new single-component white-light-emitting material Cs 2 MnCl 4 :Eu 2+ based on the combination of a lead-free halide structure and a rare-earth ion is first reported. Benefiting from the smart dilution-sensitization design strategy, white light composed of dual broad emission originating from Eu 2+ (blue light, 444 nm, 4f 6 5d 1 → 4f 7 ) and Mn 2+ (yellow light, 566 nm, 4 T 1g → 6 A 1g ) was successfully realized under near-ultraviolet light (404 nm) radiation with a high photoluminescence quantum yield of 66%. Based on the single-source Cs 2 MnCl 4 :Eu 2+ phosphor, a pc-WLEDs device with "eye-friendly" white light production was successfully fabricated. The pc-WLEDs exhibit suitable color coordinates of (0.3294, 0.2746) and a high color rendering index of 82.3, demonstrating the potential in the future health-conscious illumination application by reducing the risk of eye strain and high-energy blue-light damage. This work achieves a new single-component white-light-emitting Mn-based halide phosphor and provides a new path for the design of single-component white light sources in Mn-based halides.