Gabriel Caruntu is supported by the Macromolecular, Supramolecular and Nanochemistry (MSN) and EPSCoR programs in a CAREER award investigating the survival of ferroelectricity and geometrical ordering of the polarization at sub-micrometer length scales. These still remain elusive despite the tremendous increase in the technological importance of ferroelectric ceramics in the past decades. This CAREER project is aimed at developing a robust predictive methodology of polar ordering in nanoscale perovskites by correlating the intimate relationship between their structural, vibrational, electronic and other macroscopic properties. To this end, Prof. Caruntu designed a comprehensive experimental framework to investigate the complex interrelations between the atomic level distortions, phase transitions, evolution of microstructures, polarization reversal and switching mechanisms using aggregate-free monodisperse perovskite nanocrystals chosen as model systems. The ultimate goal is to predict the extent to which the polar ordering can be induced and manipulated at nanometer scales by finely tuning the composition, surface structure, lateral dimensions and spatial ordering of tri-dimensionally confined perovskites. The knowledge obtained from this work will conceptually broaden the field of nanoscale ferroelectrics, thereby providing new insights into size effects and surface curvature on the polar ordering in these materials. This can potentially result in the improvement of the actual design technologies in smart perovskite materials with programmable ferroelectric, dielectric and piezoelectric properties. Also, this is critical for understanding how the polar distortion and the surface structure influence the spontaneous polarization and the way the atomic dipoles are organized in ferroelectric perovskite quantum dots. Success in this research is therefore expected to extend this methodology to other metal oxide systems and inspire the implementation of these nanostructures in energy harvesting, water splitting and other energy and/or environmental-related technologies.
The societal and educational impacts of this project are strong, taking into account the technological importance of perovskite-based materials. The experimental methodology established in the group will lay a solid foundation for the development of ferroelectric-based functional nanomaterials with controlled shape/morphology and predictable properties. The research is by nature inter-disciplinary, requiring expertise from materials and computational chemistry, device design, vibrational spectroscopy, electron holography, scanning probe microscopy and colloid and surface science. Besides these fields, the project's outcomes will have a significant impact on inter-related disciplines such as energy conversion, piezoelectricity and nanomaterials design. The educational component of this project is strong and varied. The integration of research and educational components will generate broad outreach and educational activities aimed at inspiring young students to consider education and careers in chemistry, materials sciences and nanotechnology, introducing high school students, K-12 teachers, undergraduate and graduate students to the interdisciplinary field of ferroelectrics and broadening the participation of underrepresented minorities. Students will be trained in a combination of nanomaterials synthesis, physical characterization, data analysis and measurement of the physical proprieties of perovskite nanostructures. The work will also lead to the development of new courses and synergistic undergraduate and high school classroom modules that demonstrate the broad possibilities of perovskite nanomaterials for integration into different technological applications. The educational objective of this project is to train undergraduate and graduate students for future jobs in materials science, both through mentoring students from freshman to graduate level in research and by integrating the research into undergraduate and graduate level courses.
