Exploring Rare Earth-Based Nanoparticles for Use in Textiles: Integration, Optical Properties, and Potential Applications

Nanoparticles (NPs) which encompass both fluorescent and optically active types are increasingly finding applications in everyday products due to improving production efficiency and cost-effectiveness. Rare earth elements, also known as lanthanides, are widely employed for their unique optical characteristics across various fields, including optical communications, energy storage, digital displays, and bio-imaging. Although silver NPs have been effectively employed in clothing for their antimicrobial attributes, there has been limited exploration into rare earth-doped NPs as they are integrated into textiles and fabrics, which could be of significant interest to multiple industries. In this study, we focus on the integration of rare earth-based persistent luminescent NPs into textiles using various methods including spray-on, electrospinning, injection molding, and extrusion methods. These NPs were synthesized using a two-step hydrothermal synthesis followed by high-temperature sintering in an atmospheric environment. During the final sintering step at sufficiently high temperatures, additional oxygen vacancies are generated within the host crystal structure. This enables energy storage and gradual release, observed as persistent luminescence. Visible and near-infrared spectroscopy was used to assess NP emissions under ultraviolet excitation, while varying the NP loading percentage to optimize emission intensity without compromising fabric strength.