Atomic-Scale Structure of the Hematite α-Fe₂O₃(1102) "R-Cut" Surface.

ABSTRACT: The α-Fe₂O₃(11̅02) surface (also known as the hematite r-cut or (012) surface) was studied using low-energy electron diffraction (LEED), X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), scanning tunneling microscopy (STM), noncontact atomic force microscopy (nc-AFM), and ab initio density functional theory (DFT)+U calculations. Two surface structures are stable under ultrahigh vacuum (UHV) conditions; a stoichiometric (1 × 1) surface can be prepared by annealing at 450 °C in ≈10^-6 mbar O₂, and a reduced (2 × 1) reconstruction is formed by UHV annealing at 540 °C. The (1 × 1) surface is close to an ideal bulk termination, and the undercoordinated surface Fe atoms reduce the surface bandgap by ≈0.2

SUBMITTER: Kraushofer F 

PROVIDER: S-EPMC5823487 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature