Electronic and chemical structure of the H 2O/GaN(0001) interface under ambient conditions
We employed ambient pressure X-ray photoelectron spectroscopy to investigate the electronic and chemical properties of the H 2O/GaN(0001) interface under elevated pressures and/or temperatures. A pristine GaN(0001) surface exhibited upward band bending, which was partially flattened when exposed to H 2O at room temperature. However, the GaN surface work function was slightly reduced due to the adsorption of molecular H 2O and its dissociation products. At elevated temperatures, a negative charge generated on the surface by a vigorous H 2O/GaN interfacial chemistry induced an increase in both the surface work function and upward band bending. We tracked the dissociative adsorption of H 2O onto the GaN(0001) surface by recording the core-level photoemission spectra and obtained the electronic and chemical properties at the H 2O/GaN interface under operando conditions. In conclusion, our results suggest a strong correlation between the electronic and chemical properties of the material surface, and we expect that their evolutions lead to significantly different properties at the electrolyte/ electrode interface in a photoelectrochemical solar cell.
- Authors:
-
[1]
; [2]
- Univ. of Notre Dame, IN (United States). Notre Dame Radiation Lab. (NDRL); Dept. of Chemistry and Biochemistry
- Univ. of Notre Dame, IN (United States). Notre Dame Radiation Lab. (NDRL); Dept. of Physics
- Publication Date:
- Grant/Contract Number:
- FC02-04ER15533
- Type:
- Accepted Manuscript
- Journal Name:
- Scientific Reports
- Additional Journal Information:
- Journal Volume: 6; Journal ID: ISSN 2045-2322
- Publisher:
- Nature Publishing Group
- Research Org:
- Univ. of Notre Dame, IN (United States). Notre Dame Radiation Lab.
- Sponsoring Org:
- USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE
- OSTI Identifier:
- 1258572
- Free Publicly Accessible Full Text
-
Accepted Manuscript (DOE)
- Publisher's Version of Record
- https://doi.org/10.1038/srep24848