A novel orange-red emission of Ba2La8(SiO4)6O2: Sm3+ phosphor with good thermal stability and hydrophobicity

In this paper, a new type of Ba2La8(SiO4)6O2: Sm3+ phosphor was synthesized by solid-phase reaction, and the hydrophobic agent was used to restrain the hydrolysis of silicate phosphor. The microstructure, optical properties and electroluminescence properties of the samples were systematically analyzed. The results show that the Ba2La8(SiO4)6O2: xSm3+ phosphors have a strong orange-red emission at 600 nm, which corresponds to the 6G5/2→6H7/2 energy level transition of Sm3+ ions. The optimal luminescence intensity was achieved at the dopant concentration of 10 mol%. The prepared phosphor has good thermal stability, the luminescence intensity at 423 K is still 85% of that at 298 K, and the internal quantum efficiency (IQE) is 22.59%. The ultraviolet-visible-near-infrared (UV–VIS–NIR) spectrum and the density functional theory reveal that the Ba2La8(SiO4)6O2 host can provide an excellent band-gap environment for the luminescent center. In addition, the modified Ba2La8(SiO4)6O2: 0.10Sm3+ phosphor showed excellent hydrophobicity and luminescent properties, with a contact angle of 140.315°, and the luminescent intensity remained 75% of the pre-modified level. The Ba2La8(SiO4)6O2: Sm3+ phosphor has good dispersion in PVA solution and emits bright red light. The above properties indicate that Ba2La8(SiO4)6O2: Sm3+ phosphor has excellent luminescence properties and has broad application prospects.