Document Type
Thesis
Date of Award
2023
Degree Name
Master of Science (MS)
Department
Chemistry
First Advisor
Chaoyang Jiang
Abstract
As counterfeited goods appear in the consumer market through various trade routes, unsuspecting buyers are left with products that are potentially dangerous and in poor quality. Products intended for the automotive and aerospace industry are often counterfeited due to their easy market accessibility. Once these products make their way into the supply chain, it leaves the end users with a significant risk due to voided warranties and inferior product quality and design. Therefore, advanced anti-counterfeiting measures need to be developed to assure the products are genuine, as well as allow the end users to authenticate the product. Luminescent materials have already been routinely used by state and federal government agencies for security of documentation and currency. Quite often, fluorescence features are the only mode for the function of these luminescent materials. Furthermore, there have been few studies on the study of dynamic luminescence properties for security materials. In this work, we explored the feasibility of using a metal doped calcium zinc germanate (CZGO) for the applications in multi-level dynamic anti-counterfeiting labels. The CZGO materials were synthesized by a high temperature solid state reaction. A systematic study of the material crystallinity was conducted on CZGO phosphors that are synthesized with various reaction times, temperatures, and dopant concentration. With the optimized synthetic conditions, photoluminescence properties of the metal doped-CZGO were investigated using fluorophotometry. Tunable dynamic fluorescence and phosphorescence were studied in detail, and its luminescence mechanism was proposed. Finally, examples of using the metal doped-CZGO in anti-counterfeiting labels were demonstrated. This work has demonstrated a great potential of using the newly developed CZGO materials as a new generation of anti-counterfeiting labels with multi-level dynamic optical features.
Subject Categories
Chemistry
Keywords
DYNAMIC LUMINESCENCE, LEAD DOPED, CALCIUM ZINC GERMANATE, ANTI-COUNTERFEITING
Number of Pages
68
Publisher
University of South Dakota
Recommended Citation
Spencer, Levi, "DYNAMIC LUMINESCENCE OF LEAD DOPED CALCIUM ZINC GERMANATE FOR ANTI-COUNTERFEITING" (2023). Dissertations and Theses. 187.
https://red.library.usd.edu/diss-thesis/187