Design, Synthesis, and Characterization of a Novel Blue-Green Long Afterglow BaYAl₃O₇:Eu²⁺, Nd³⁺ Phosphor and Its Anti-Counterfeiting Application

• Published in: Nanomaterials
• Main Authors: Jiao Wu, Quanxiao Liu, Peng Gao, Jigang Wang, Yuansheng Qi, Zhenjun Li, Junming Li, Tao Jiang
• Format: Article
• Language: English
• Published: MDPI AG 2023-08-01
• Subjects: long afterglow; BaYAl₃O₇:Eu²+, Nd³+; screen printing; anti-counterfeiting
• Online Access: https://www.mdpi.com/2079-4991/13/17/2457

Herein, a series of novel long afterglow nanophosphors BaYAl₃O₇:Eu²⁺, Nd³⁺ was synthesized by the combustion method. The investigation encompassed the characterization of X-ray diffraction, morphology, chemical valence, elemental composition, and photoluminescence behavior of BaYAl₃O₇:Eu²+ and BaYAl₃O₇:Eu²⁺, Nd³⁺ nanoparticles. Under 365 nm excitation, BaYAl₃O₇:Eu²⁺ and BaYAl₃O₇:Eu²⁺, Nd³⁺ show emission bands centered at 497 nm and 492 nm, which are attributed to the 4f⁶5d→4f⁷ transition of Eu²⁺ ions. The optimal samples of BaYAl₃O₇:0.03Eu²⁺ and BaYAl₃O₇:0.03Eu²⁺, 0.02Nd³⁺ have average fluorescence lifetimes of 850 ns and 1149 ns, respectively. The co-doping of Nd³+ ions as the trap centers produced long afterglow luminescence properties, and the afterglow time could reach up to 8 min. Furthermore, the fluorescent powder can be mixed with polyacrylic acid to prepare anti-counterfeiting inks; a clover pattern and snowflake pattern have been successfully printed using screen printing technology, proving its potential application in the field of anti-counterfeiting.