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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
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Interface Structure, Band Alignment, and Built-In Potentials at LaFeO_{3}/n-SrTiO_{3} Heterojunctions
Ryan Comes1,2, Scott Chambers1
1Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
Physical Review Letters
|December 8, 2016
Summary
Interface polarity in oxide heterostructures like LaFeO3/n-SrTiO3 significantly impacts electronic properties. Engineered interfaces show similar band offsets but differing potential gradients, potentially aiding photocatalysis applications.
Area of Science:
- Solid State Physics
- Materials Science
- Surface Science
Background:
- Interface structure is crucial for emergent phenomena in oxide heterostructures.
- The LaFeO3/n-SrTiO3 system serves as a model for polar-nonpolar interfaces.
Purpose of the Study:
- To investigate the influence of interface polarity on electronic properties of LaFeO3/n-SrTiO3 heterojunctions.
- To correlate interface engineering with potential applications in photocatalysis.
Main Methods:
- Epitaxial growth of LaFeO3/n-SrTiO3(001) heterojunctions.
- High-energy-resolution X-ray Photoemission Spectroscopy (HER-XPS) for electronic structure analysis.
Main Results:
- Engineered interfaces with opposite polarities exhibited similar band offsets and potential gradients within LaFeO3 films.
- Significant differences in potential gradients were observed within the SrTiO3 layer based on interface polarity.
Conclusions:
- Interface polarity critically influences the electronic band structure and potential gradients in oxide heterostructures.
- Tailoring the potential gradient in SrTiO3 may enhance hole diffusion for improved photocatalysis.
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