Understanding the Impacts of Impurities on Processing

点击翻译按钮获取中文摘要

NON-TECHNICAL DESCRIPTION: Impurities exist in almost all raw materials and precursors and the removal of such impurities can be time-consuming, energy intensive and very costly. In contrast, this project is to investigate the positive impacts impurities can have to promote the development of high energy crystal facets, and surface and bulk defects in a model system, vanadium pentoxide, with much desired chemical, electrochemical, and catalytic properties for energy conversion and storage. These impurities can modify the bulk and surface chemistry, morphology, crystallinity, and the physical properties of the resulting crystallites, and thereby significantly impact their performance and applications. Although the doping in semiconductors (at the electronic grade or ppm level) and the doping in oxides for ionic conductors (at metallurgical grade or a few percent) have been well studied and understood, there is limited information on the impacts of impurities on the processing, morphology, and properties of the resulting crystallites that are widely used in energy conversion and storage as well as many other applications including environment monitoring and remediation. TECHNICAL DETAILS: This project is to investigate the influences and impacts of impurities on the processing, morphology and properties of inorganic materials with vanadium pentoxide as a model system, focusing on submicrometer or nanometer sizes, and their applications in energy conversion and storage. Impurities, often accompanied with other defects such as oxygen vacancies may also be incorporated into the crystal lattice or reside on the surface. Such impurities can modify the bulk and surface chemistry, crystallinity, morphology, and the physical properties of the resulting crystallites away from thermodynamic equilibrium and, thus, significantly impact on their performance and applications with much reduced processing cost. The results generated by this project will enrich the fundamental understanding of the impurities on the processing, morphologies and properties of materials. Broader impacts are envisioned through the recruitment of diverse students; fostering a positive culture that accepts, respects, and tolerates differences of others; training of both undergraduate and graduate students; incorporating recent research results into courses; and working cooperatively with Pacific Northwest National Laboratory (PNNL).