Surface organic modification of SrAl2O4: Eu2+, Dy3+ via coupling agents to enhance hydrolysis resistance

• Published in: Journal of materials science. Materials in electronics 2021-08, Vol.32 (15), p.20804-20816
• Main Authors: Shi, Muyang, Lu, Bohui, Jin, Yang, Ge, Mingqiao
• Format: Article
• Language: English
• Subjects: Aqueous environments; Characterization and Evaluation of Materials; Chemistry and Materials Science; Contact angle; Coupling agents; Crystal structure; Emission analysis; Emission spectra; Europium; Fourier transforms; Gravimetric analysis; Hydrolysis; Infrared spectroscopy; Luminous efficacy; Luminous intensity; Materials Science; Morphology; Optical and Electronic Materials; Organic materials; Phosphors; Photoluminescence; Spectrum analysis; Stability analysis; Surface properties; Thermal analysis
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-021-06594-y

SrAl 2 O 4 : Eu 2+ , Dy 3+ (SAO), an important luminescent material, is widely used in security signs and entertainment because of its high luminous efficiency and a long persistent afterglow. However, the agglomerate behavior and poor hydrolysis resistance of SAO phosphors limit their applications in organic materials, particularly in an aqueous environment. Herein, a facile and effective approach based on the coupling agent for coating SAO phosphors is reported. The surface modification effects were characterized via Fourier transform infrared spectroscopy (FT-IR); the phase and crystal structures were investigated using X-ray diffraction (XRD); and the micro-morphology of phosphors was examined using scanning electron microscopy (SEM). The modified SAO phosphors had a coarse surface. Contact angle and pH analysis indicated that the surface property of the modified SAO phosphors was changed from hydrophilic (20°) to hydrophobic (141°), and a superior hydrolysis resistance was achieved. Thermodynamic stability was analyzed using thermal gravimetric analysis (TGA). Photoluminescence emission spectra and afterglow curve measurements showed that the surface modification only slightly influenced the luminous intensity. Finally, a coated fabric was prepared using the modified SAO phosphors, and it exhibited excellent luminescence and hydrolysis resistance. Thus, the proposed method can be used to obtain surface organic-modified SAO phosphors for various applications.