CAREER: Investigating Inversion in High Entropy Oxide Spinels- Unraveling Structural Dynamics for Advanced Materials Design

About This Grant

NON-TECHNICAL SUMMARY: This research project investigates how disorder at the atomic level in materials can be deliberately controlled to create new and customizable properties for technological application. The focus is on high entropy oxides, a unique class of materials formed by combining multiple chemical elements in unconventional combinations. By examining how this disorder influences magnetic and electronic behaviors, the research uncovers strategies for designing advanced materials tailored for technologies like energy storage, electronics, and data storage. A central question in materials science is how much atomic-level disorder can be manipulated to achieve specific, desired properties. This project addresses that question, providing crucial insights into the relationship between disorder and material performance. It also develops an understanding of how different processing conditions can fine-tune these properties, paving the way for practical applications in cutting-edge technologies. This project fosters education in science and engineering through the development of online learning tools to support graduate students from various academic backgrounds, hands-on research opportunities for undergraduates, and community outreach programs that spark interest in science among middle and high school students. By advancing the ability to engineer materials through controlled disorder and promoting STEM education, this work drives technological innovation while inspiring and preparing the next generation of scientists and engineers. TECHNICAL SUMMARY: This project investigates the influence of compositional complexity on cation inversion in high entropy spinel oxides (HESOs) and its impact on their magnetic and electronic properties. High entropy spinel oxides are a class of materials stabilized by high configurational entropy, enabling unique combinations of cation site occupancy. The research aims to test the hypothesis that compositional complexity and processing conditions can be used to finely control cation inversion, enabling tailored functional properties such as tunable magnetism and electronic behavior. The research addresses three key questions: (1) how does increasing the number of components in high entropy compositions affect cation inversion; (2) how does variation in component ratios influence inversion trends; and (3) how do synthesis and processing conditions, such as temperature and pressure, impact inversion and functional properties? The scope of the work includes synthesizing bulk, single-phase HESO compositions with varying degrees of configurational complexity through solid-state processing methods. Combinations of laboratory-based and synchrotron characterization techniques, including but not limited to X-ray diffraction, X-ray absorption spectroscopy, magnetometry, and computational modeling, are employed to investigate the structure-process-property relationships. This approach provides insight into how entropic contributions can overcome conventional crystal field stabilization energies, influencing site occupancy and property tunability. The findings will contribute to the broader understanding of thermodynamic behavior and disorder in HESOs and the tunability of said disorder, while supporting data generation for machine learning applications in complex materials. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.