Synthesis of organic-inorganic hybrid nanoparticles and their application in additive manufacturing
In recent years, organic-inorganic hybrid nanoparticles (OIHNs) have caught the attention of both academia and industry since well-established classes of materials, such as metals, polymers, and ceramics, maybe limited in their properties. These traditional materials cannot satisfy the requirements needed for many novel applications, such as sensor biohybrid materials, and photonic devices. OIHNs, on the other hand, have properties unique to inorganic nanoparticles, such as chemical resistivity, as well as the easy processability of organic materials. For example, OIHNs created in our group by integrating organic ligands with low extreme ultraviolet (EUV) radiation absorption, together with high-absorption metal-oxide nanoparticles, such as ZrO2- and HfO2-, may be useful as a future material for EUV lithography. Chapter 1 focuses on the synthesis of hairy nanoparticles (HNPs). Specifically, silica- poly(methyl methacrylate) (SiO2-PMMA) nanoparticles were synthesized using an Activator Regenerated by Electron Transfer - Atomic Transfer Radical Polymerization (ARGET-ATRP) in mini-emulsion. The influence of Sample parameters such as MMA concentration and MMA feeding rate, as well as the roles of acetone and tetra-n-butylammonium bromide (TBAB) on the brush canopy size, graft density, Mn of the grafted polymer chains, and Sample kinetics, were investigated. In the future, the resulting, well-defined HNPs may serve as important building blocks in the creation of functional superlattices by tailoring polymer entanglement and interactions between HNPs. Chapter 2 highlights a specific application of OIHNs. The surfaces of zinc oxide nanoparticles were modified with photosensitive ligands for the purpose of three-dimensional (3D) printing. These zinc oxide nanoparticles were used as nano-building blocks to enable the fabrication of complex, arbitrary 3D geometries at room temperature using Digital Light Processing (DLP) stereolithography, with a resolution approaching 50 μm. Moreover, the electronic properties of the 3D metal oxide structure remaining after calcination were studied by transmission line measurement. These proof-of-concept results open up a broad opportunity space for 3D printing zinc oxide mesostructures in applications such as optoelectronics.
Ober, Christopher Kemper
Materials Science and Engineering
M.S., Materials Science and Engineering
Master of Science
dissertation or thesis