LAUSR

β-Sialon:Eu2+ has been reported to be the most promising narrow-band green phosphor for wide color gamut LCD backlights, but the coexistence of the Eu3+ luminescence killer with the Eu2+ luminescence center limits its luminescence performance to a great extent. In this study, we propose a direct reduction strategy to successfully realize the reduction of Eu3+ to Eu2+ and, finally, increase the effective concentration of Eu2+ in the crystal lattice and greatly minimize the amount of Eu3+ on the particle surface. As a result, the luminescence of treated β-sialon:Eu2+ is enhanced by 2.3 times, and the internal quantum efficiency significantly increases from 52.2 to 96.5%. The mechanisms for such large enhancements in luminescence are clarified by investigating the microstructure, luminescence spectra, valence state, concentration, and distribution of Eu using a variety of chemical analyses. We find that the low efficiency is ascribed to the coexistence of the Eu3+ luminescence killer with the Eu2+ luminescen...