The oxidation of chromium in air at 700 °C was investigated with a focus on point defect behavior and transport during oxide layer growth. A comprehensive set of characterization techniques targeted characteristics of chromium oxide microstructure and chemical composition analysis. TEM showed that the oxide was thicker with longer oxidation times and that, for the thicker oxides, voids formed at the metal/oxide interface. PAS revealed that the longer the oxidation time, there was an overall reduction in vacancy-type defects, though chromium monovacancies were not found in either case. EIS found that the longer oxidized material was more electrochemically stable and that, while all oxides displayed p-type character, the thicker oxide had an overall lower charge carrier density. Together, the results suggest anion oxygen interstitials and chromium vacancy cluster complexes drive transport in an oxidizing environment at this temperature, providing invaluable insight into the mechanisms that regulate corrosion.
Auguste, R., et al. "A multimodal approach to revisiting oxidation defects in Cr2O3." npj Materials Degradation, vol. 6, no. 1, Jul. 2022. https://doi.org/10.1038/s41529-022-00269-7
Auguste, R., Chan, H. L., Romanovskaia, E., Qiu, J., Schoell, R., Liedke, M. O., Butterling, M., Hirschmann, E., Attallah, A. G., Wagner, A., Selim, F. A., Kaoumi, D., Uberuaga, B. P., Hosemann, P., & Scully, J. R. (2022). A multimodal approach to revisiting oxidation defects in Cr2O3. npj Materials Degradation, 6(1). https://doi.org/10.1038/s41529-022-00269-7
Auguste, R., Chan, H. L., Romanovskaia, E., et al., "A multimodal approach to revisiting oxidation defects in Cr2O3," npj Materials Degradation 6, no. 1 (2022), https://doi.org/10.1038/s41529-022-00269-7
@article{osti_1877955,
author = {Auguste, R. and Chan, H. L. and Romanovskaia, E. and Qiu, J. and Schoell, R. and Liedke, M. O. and Butterling, M. and Hirschmann, E. and Attallah, A. G. and Wagner, A. and others},
title = {A multimodal approach to revisiting oxidation defects in Cr2O3},
annote = {Abstract The oxidation of chromium in air at 700 °C was investigated with a focus on point defect behavior and transport during oxide layer growth. A comprehensive set of characterization techniques targeted characteristics of chromium oxide microstructure and chemical composition analysis. TEM showed that the oxide was thicker with longer oxidation times and that, for the thicker oxides, voids formed at the metal/oxide interface. PAS revealed that the longer the oxidation time, there was an overall reduction in vacancy-type defects, though chromium monovacancies were not found in either case. EIS found that the longer oxidized material was more electrochemically stable and that, while all oxides displayed p-type character, the thicker oxide had an overall lower charge carrier density. Together, the results suggest anion oxygen interstitials and chromium vacancy cluster complexes drive transport in an oxidizing environment at this temperature, providing invaluable insight into the mechanisms that regulate corrosion.},
doi = {10.1038/s41529-022-00269-7},
url = {https://www.osti.gov/biblio/1877955},
journal = {npj Materials Degradation},
issn = {ISSN 2397-2106},
number = {1},
volume = {6},
place = {United Kingdom},
publisher = {Nature Publishing Group},
year = {2022},
month = {07}}