Powder X-ray Diffraction for Geosciences and Innovative Materials

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Powder X-ray diffraction (PXRD) is a powerful and indispensable analytical tool in modern materials and geosciences. It allows to establish structure-property relationship needed to design next-generation materials, is key to unlock solutions to waste management in mining, understand environmental contaminant cycling, access engineering properties of soil, and for advanced building applications. The uOttawa X-ray Core Facility houses a - Ultima IV system with a Cu source, diffracted-beam monochromator and scintillation detector. Yet, this configuration prevents progress for the applicants' research programs. Hence, this proposal aims to equip the system with a fast silicon-strip detector (Rigaku D/teX Ultra) and a temperature-controlled sample chamber (Rigaku SHT1500). The applicants urgently need these components to support specific aspects of their research and HQP training: 1. Hemmer's research focuses on the design of next-generation optical and magnetic rare-earth-based materials including chemically-controlled synthesis and establishment of structure-property relationships. The D/teX Ultra's low detection limits are needed to detect and identify secondary phases and to correlate crystal structure with material performance. 2. Al's research aims to prevent contamination of natural waters by transforming soluble As2O3 mine waste to low solubility compounds. PXRD must be conducted with low detection limits and rapid acquisition times to identify the products and quantify the reaction kinetics, enabled with the D/teX Ultra and the SHT1500 chamber. 3. Fortin studies the properties of natural ferrihydrite and how it affects environmental contaminant cycling. Natural ferrihydrite contains impurities. To unveil the effect of these impurities on contaminant cycling, XRD analyses must be conducted with the mineral in the natural hydrated state and at temperatures that simulate seasonal variations. The ultra-sensitive detector and the inert chamber will make this possible. 4. Vanapalli seeks to understand how Microbially- and Bacterial-Enzyme-Induced Calcite Precipitation can be used to improve the strength of soils and to develop erosion control measures. The D/teX Ultra's low detection limits are critical to the success of this research. 5. Foruzanmehr's research focuses on the modification of cellulosic materials for advanced building applications. Finding the crystallinity index of semi-crystalline materials is a key indicator for the degradation of natural fibers in these materials. Without the D/tex detector and SHT1500 chamber, index values are imprecise and erroneous, making the equipment an urgent need. Moreover, transforming the existing into a state-of-the-art PXRD will benefit the entire user community at uOttawa by expanding capabilities and increasing sample throughput.