Multifunctional Materials: Synthesis and Optical Properties of Rare-Earth Nanocrystals for Technological Applications
Multifunctional photonic nanomaterials are of great interest for a wide range of technological and medical applications, ranging from optoelectronic devices and data transmission, to medical imaging and therapy. Key interests in recent times have been in combining functionalities to produce more versatile materials, as well as increasing performance and efficiency, and developing cost-effective, scalable, and efficient synthesis processes. In particular, rare-earth based nanomaterials have been studied due to their extraordinary optical and magnetic properties. In this dissertation, multiple methods are explored to optimize synthesis routes and improve performance of these materials. The use of unconventional energy transfer between co-doped rare-earths has shown a significant improvement in optical emissions of NaGdF4 :Nd3+ ,Yb3+ nanoparticles. The synthesis of Er3+ -doped Yttrium Aluminum Garnet nanocrystals is shown to provide excellent optical properties compared to their single crystal and polycrystalline ceramic counterparts, with a simpler and more efficient synthesis method. Au and Ag alloyed yolk-shell structures have been successfully synthesized, which can be combined with rare-earth-based nanomaterials where localized surface plasmon resonance can be used to further enhance the optical properties of rare-earths.