High-Resolution X-ray Photoelectron Spectroscopy of an IrO₂(110) Film on Ir(100)

TY - JOUR

T1 - High-Resolution X-ray Photoelectron Spectroscopy of an IrO2(110) Film on Ir(100)

AU - Martin, R.

AU - Kim, M.

AU - Lee, C. J.

AU - Mehar, V.

AU - Albertin, S.

AU - Hejral, U.

AU - Merte, L. R.

AU - Lundgren, E.

AU - Asthagiri, A.

AU - Weaver, J. F.

PY - 2020/9/3

Y1 - 2020/9/3

N2 - High-resolution X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) were used to characterize IrO2(110) films on Ir(100) with stoichiometric as well as OH-rich terminations. Core-level Ir 4f and O 1s peaks were identified for the undercoordinated Ir and O atoms and bridging and on-top OH groups at the IrO2(110) surfaces. Peak assignments were validated by comparison of the core-level shifts determined experimentally with those computed using DFT, quantitative analysis of the concentrations of surface species, and the measured variation of the Ir 4f peak intensities with photoelectron kinetic energy. We show that exposure of the IrO2(110) surface to O2 near room temperature produces a large quantity of on-top OH groups because of reaction of background H2 with the surface. The peak assignments made in this study can serve as a foundation for future experiments designed to utilize XPS to uncover atomic-level details of the surface chemistry of IrO2(110).

AB - High-resolution X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) were used to characterize IrO2(110) films on Ir(100) with stoichiometric as well as OH-rich terminations. Core-level Ir 4f and O 1s peaks were identified for the undercoordinated Ir and O atoms and bridging and on-top OH groups at the IrO2(110) surfaces. Peak assignments were validated by comparison of the core-level shifts determined experimentally with those computed using DFT, quantitative analysis of the concentrations of surface species, and the measured variation of the Ir 4f peak intensities with photoelectron kinetic energy. We show that exposure of the IrO2(110) surface to O2 near room temperature produces a large quantity of on-top OH groups because of reaction of background H2 with the surface. The peak assignments made in this study can serve as a foundation for future experiments designed to utilize XPS to uncover atomic-level details of the surface chemistry of IrO2(110).

UR - http://www.scopus.com/inward/record.url?scp=85090298042&partnerID=8YFLogxK

U2 - 10.1021/acs.jpclett.0c01805

DO - 10.1021/acs.jpclett.0c01805

M3 - Article

C2 - 32787312

AN - SCOPUS:85090298042

VL - 11

SP - 7184

EP - 7189

JO - The Journal of Physical Chemistry Letters

JF - The Journal of Physical Chemistry Letters

SN - 1948-7185

IS - 17

ER -