Thermal-responsive multicolor emission of single NaGdF 4 :Yb/Ce/Ho upconversion nanocrystals for anticounterfeiting application

Nanophotonics

article

Yanqing Hu¹  Qiyue Shao¹  Xinyi Deng¹  Jianqing Jiang¹ 

[1] School of Materials Science and Engineering, Jiangsu Key Laboratory for Advanced Metallic Materials, Southeast University;School of Mechanical and Electronic Engineering, Nanjing Forestry University

关键词: anticounterfeiting;    luminescence;    nanocrystals;    quenching;    upconversion;   

DOI  :  10.1515/nanoph-2020-0136

学科分类：社会科学、人文和艺术（综合）

来源: De Gruyter

【 摘 要 】

This study presents a novel and high-level anticounterfeiting strategy based on Ce/Yb/Ho triply-doped NaGdF 4 nanocrystals with temperature-responsive multicolor emission. A critical factor leading to the multicolor emission is confirmed by comparing the luminescence thermal behaviors of nanocrystals in various atmospheres. Through analyzing the temperature-dependent lifetimes of Yb 3+ ions in air, we demonstrate that thermally-induced multicolor emission mainly originates from the gradually-attenuated H 2 O quenching effect. Because the cross-relaxations between Ce 3+ and Ho 3+ ions and the nonradiative transitions of Yb 3+ ions create plenty of phonon heat, the multicolor emission of nanocrystals can be achieved under 975 nm excitation at a relatively low power density. This recognition method is efficient and convenient for security authentication. The as-synthesized core nanocrystals can be directly used to fabricate anticounterfeiting ink without further processing (e.g. core/shell or hybrid). Therefore, the small-sized β-NaGdF 4 :Yb/Ce/Ho nanocrystals are promising candidate for security application.

【 授权许可】

CC BY