Electron tunneling characteristics on La[subscript 0.7]Sr[subscript 0.3]MnO[subscript 3] thin-film surfaces at high temperature
We report on the electron tunneling characteristics on La0.7Sr0.3MnO3 (LSM) thin-film surfaces up to 580 °C in 10[superscript −3] mbar oxygen pressure, using scanning tunneling microscopy/spectroscopy (STM/STS). A thresholdlike drop in the tunneling current was observed at positive bias in STS, whic...
| Main Authors: | , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
American Institute of Physics
2011
|
| Online Access: | http://hdl.handle.net/1721.1/67334 https://orcid.org/0000-0002-2688-5666 |
| Summary: | We report on the electron tunneling characteristics on La0.7Sr0.3MnO3 (LSM) thin-film surfaces up to 580 °C in 10[superscript −3] mbar oxygen pressure, using scanning tunneling microscopy/spectroscopy (STM/STS). A thresholdlike drop in the tunneling current was observed at positive bias in STS, which is interpreted as a unique indicator for the activation polarization in cation-oxygen bonding on LSM cathodes. Sr-enrichment was found on the surface at high temperature using Auger electron spectroscopy, and was accompanied by a decrease in tunneling conductance in STS. This suggests that Sr-terminated surfaces are less active for electron transfer in oxygen reduction compared to Mn-terminated surfaces on LSM. |
|---|