Overview
In the Moreau group, our work falls under four key subareas: actinide nanomaterials, nanoparticles for radiotherapy, crystal nucleation, growth and degradation, and development of X-ray analysis tools.
Actinide nanomaterials
This is the primary thrust area of the group. We are synthesizing actinide nanomaterials using three distinct approaches: 1) colloidal synthesis in organic phase solution, 2) incorporation of nanoparticles into porous templates, focusing on metal organic frameworks, and 3) electrochemical synthesis. Each approach has its own advantages and disadvantages towards studying fundamental properties, surface-based interactions and environmental interface systems. In our group, we take the approach of synthesizing particles not only for functionality, but towards optimizing systems that allow us to best extract their fundamental properties through comprehensive characterization using X-ray focused approaches. X-rays are particularly useful for studying radioactive materials due to the ability to contain samples based on the high penetrating capability of hard X-rays. Fundamental properties and pathways studied will lead to the proposal of advanced nanoscale nuclear fuel materials and improved knowledge of how actinides interact with environmental systems. Rather than collecting and analyzing existing nuclear waste or separations optimization, our approach focuses on deriving the fundamental design rules that govern actinide speciation and mobility from materials development to long-term degradation and storage.
Nanoparticles for radiotherapy
Through incorporation of medical isotopes into nanoparticles, we aim to develop generalized approaches to target tumor sites specifically without exposing other bodily tissue to radiation that can destroy healthy tissue. Isotopes are directly incorporated into the inorganic nanoparticle core rather than surface-bound molecules, in order to better confine them and prevent release. We use approaches that are both based on doping biologically compatible nanoparticles with medical isotopes and approaches that rely on in-situ activation of material to create radioisotopes. This latter approach involves fundamental studies of how radiation interacts with materials and if nanoscale effects affect these processes.
Crystal nucleation, growth and degradation
More broadly within the field of nanotechnology, we are interested in the parameters that define nanoparticle nucleation, growth and transformation pathways. In particular, reduction kinetics within metal nanoparticles and between relative alloy species are of interest. A primary focus is also on understanding the chemistry of the surface species that stabilize high-energy interfaces. Through using an X-ray spectroscopy-focused approach on ultra-small nanoparticles we can extract surface charge and binding characteristics as a function of surface ligand species and track how this changes through ligand exchange processes. In some cases we are exploring these parameters within the realm of actinide particles developed, but we are also fundamentally exploring nanoparticles from various parts of the periodic table where surface chemistry and growth affects are relevant to their intended application.
Development of X-ray analysis tools
The Moreau group specializes in X-ray spectroscopy and X-ray scattering tools. In addition to using these tools to probe structural and electronic attributes of nanoparticle systems, the group puts efforts towards increasing the accessibility of these tools towards solving challenging problems within nanomaterials characterization and radiological materials characterization. This includes development of code and methodology to extract SAXS patterns for samples with complex backgrounds, evaluating limits of detection of secondary phases via X-ray spectroscopy, and determining new methods of conducting materials surface analysis. Additionally, the group works to design and fabricate sample cells that are both functional and enable safe measurement of radioactive isotopes.
