Maria Gomez of Mount Holyoke College is supported by a RUI award for research that aims to understand how dopant size and electronic character affect preferred proton conduction pathways. A systematic study of doped perovskite oxides will be carried out. In particular, minimum energy binding sites, transition state activation energies, and transition state pre-factors will be calculated as a function of dopant. With relative site energies and pre-factors, the energetically and kinetically preferred pathways will be found using adjacency matrices and Kinetic Monte Carlo. From molecular dynamics calculations starting at different binding sites within the preferred conduction pathways, vibrational spectra will be calculated. Comparisons with experiment will help correlate spectral features with OH vibrations and different binding sites. Finally, investigations into how the addition of protons into doped perovskites changes binding energies, transition states, and lowest energy pathways will begin.
Proton conduction in perovskite oxides has potential applications in fuel cell technologies, humidity sensors, and batteries. The knowledge gained from this research is expected to aid in designing efficient proton conducting perovskites. This project has a broader impact in the training of future scientists, and is being carried out entirely with undergraduate student researchers at Mount Holyoke College, the oldest continuing undergraduate liberal arts college for women in the United States. The student participants will present their undergraduate research at national or regional meetings, and co-author publications.