CAREER: Correlating the Microstructure with the Physical Properties of Perovskite and Related Oxide Materials

Southern University, Baton Rouge LA

Investigators

Abstract

This CAREER project focuses on understanding the mechanisms that govern ion transport in perovskites and related oxides (PRO) with interesting and useful ionic transport properties. Specifically, this project will investigate the correlation of microstructure of PRO's with their physical properties to elucidate the structural and compositional factors that influence the ionic conductivity. The project involves the low temperature synthesis of nanocrystalline PRO's such as La0.6Sr0.4MnO3 with varying compositions and crystallite sizes using the novel 3,3',3"-nitrilotripropionic acid precursor gel method and the characterization of the nanocrystalline PRO's using X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) in conjunction with impedance spectroscopy to investigate the relationship between structure, composition, and physical properties (ion transport in particular). Structural and conductivity data will be analyzed and correlated to determine the relationship between grain size, grain boundaries, defects and vacancies on bulk ion diffusion. Undergraduate students will participate significantly in the synthesis, characterization, and physical analysis of these oxide-conducting materials. This CAREER project will yield new insights into the mechanisms that govern ion transport in PRO's. Since the possible composition of perovskites and their electronic and ionic transport properties remain relatively unexplained, the successful investigation of the structural and compositional factors that influence the ionic conductivity in nanocrystalline PRO ion conductors in this study will represent a relatively significant contribution to the area of solid-state PRO conductors. A better understanding of ionic transport in PRO's will have a significant impact on the economic and commercial barriers in a multitude of applications ranging from portable devices to homes and vehicles. Additionally, this project will also have a significant impact on under-represented minority students at Southern University, a Historically Black College and University and a Primarily Undergraduate Institution, by exposing them to materials science-related research, a field where the numbers of minority students are very scarce. Students will be given the opportunity for hands-on experience that results in a more meaningful undergraduate research experience.