Synthesis and Characterization of Cobalt Oxide Perovskites

Abstract

Cobalt-containing materials host a wide range of exotic electronic and magnetic phenomena. Understanding the behavior of these materials under varying conditions may provide clues to the fundamental chemistry which directs cobalt’s unusual behavior. In these experiments, I looked to synthesize and characterize materials which would result in a non-standard cobalt oxidation state or coordination environment. To this end, I focused on synthesizing Y1-xCaxCoO3, YIn1-xCoxO3 and REIn0.95Co0.05O3. I report successful synthesis of single phase YIn1−xCoxO3 for 0.025 < x < 0.075. These doped materials were a rich green color and showed diamagnetic and paramagnetic behavior. However, the magnetic response of these compounds was very weak and requires additional magnetic analysis. In addition, I successfully synthesized REIn0.95Co0.05O3 (RE = Eu, Gd, Tb, Dy). These materials showed spin frustration, in accordance with reported magnetic behavior of undoped REInO3 in the literature. Synthesis of Y1-xCaxCoO3 was unsuccessful in this study. Future work on these projects may involve additional structural analysis to determine the nuances of the cobalt coordination environment, additional characterization of these materials’ electronic and magnetic properties, and synthesis of related compounds to better isolate and understand the effects of cobalt in these systems.