Document Type


Date of Award


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Chaoyang Jiang


Counterfeiting poses a significant threat to public health and safety, necessitating robust measures to combat it. Addressing this challenge requires the development of advanced materials and techniques, coupled with a comprehensive understanding of the obstacles inherent in anti-counterfeiting endeavors. Our study delved into two approaches for crafting anti-counterfeiting technologies: plasmonic and luminescence materials. We thoroughly examined the challenges associated with each method and proposed viable solutions. Notably, we devised a streamlined process for producing inkjet printable Surface-enhanced Raman Scattering (SERS) ink, enabling the creation of low-cost covert quick response (QR) codes with a high storage capacity. Access to the encoded information from the QR codes is restricted to using a confocal Raman microscope so that the security level is strengthened. In addition, our research demonstrated that multiple QR codes could be printed on the same security label, further enhancing their complexity. In the second approach, we engineered two types of germanate phosphor materials that have novel and lesser-known optical properties, such as photostimulated luminescence (PSL) and dynamic fluorescence. We systemically synthesized metal-doped germanate with various dopant concentrations and studied these materials' optical properties. The mechanism of PSL and dynamic fluorescence were proposed based on the observed experimental results. These phosphor materials were then utilized to fabricate several anti-counterfeiting applications, demonstrating their high security and exceptional versatility. The verification process of these luminescence-based anti-counterfeiting applications involves using a UV light and/or an iPhone, thereby offering a portable and user-friendly approach to anticounterfeiting. Overall, our research provides invaluable insights that can promote the development and implementation of novel anti-counterfeiting strategies.

Subject Categories



Counterfeiting, Plasmonic materials, Luminescence materials, Surface-enhanced Raman Scattering (SERS) ink, Quick response (QR) codes, Confocal Raman microscope, Photostimulated luminescence (PSL), UV light

Number of Pages



University of South Dakota

Available for download on Sunday, April 26, 2026

Included in

Chemistry Commons