Phosphor-in-glass with full-visible-spectrum emission based on ultra-low melting Sn-F-P-O glass pumped by NUV LED chips

Herein, the phosphor-in-glass (PiG) with full-visible-spectrum emission has been successfully fabricated by incorporating SrSi₂O₂N₂: Eu²⁺ (SSON:Eu) and CaAlSiN₃: Eu²⁺ (CASN:Eu) phosphors in ultra-low melting Sn-F-P-O glass using one-step sintering method. The Sn²⁺ ions show intense blue-green emission characteristics under the excitation of NUV chips, which are highly dependent on its coordination environment in Sn-F-P-O glass. Then, it was investigated in detail for the first time that fluoride from Sn-F-P-O glass substrate migrates and gathers around the embedded phosphors, which is closely related to the emission performance of Sn²⁺ activators in the PiG. Furthermore, the mechanism of enhancing the PL intensity of Sn²⁺ ions by embedded phosphors is proposed. As a result, the PiG with full-visible-spectrum emission can be achieved under 370 nm excitation. Importantly, the PiG pumped by NUV LED chips shows excellent-quality white-light with high CRI (Ra = 91) and lower CCT (4993 K). The WLED based on this PiG has been demonstrated as a promising candidate for solid warm light source in the future because of the excellent optoelectronic performance and easy-preparation process.