[Zurück]

J. Redondo, P. Kocán, G. Franceschi, F. Kraushofer, M. Riva, G. Parkinson, M. Schmid, U. Diebold, M. Setvin, I. Sokolovic:
"Investigations of polarons in hematite α−Fe₂O₃(1102) by means of nC-AFM and KMC";
Poster: DPG-Frühjahrstagung (DPG Spring Meeting) of the Surface Science Division, SurfaceScience21, virtual; 03.03.2021.

Polarons are known to strongly influence the catalytic activity and the electronic, magnetic and structural properties of transition metal oxides and halide perovskites. The study of polaron formation and dynamics is fundamental to understanding the actual mechanisms and yields of catalytic reactions in these materials. A new method for the investigation of electron- and hole- polarons is demonstrated. Charge carriers are injected with the atomic force microscope (AFM) tip into the α−Fe2O3(1102) surface. The injected charges form a cloud of charged particles trapped in the lattice. This cloud expands due to electrostatic interactions and thermally activated polaron hopping. Controlled annealing the sample and characterization by Kelvin probe force microscopy (KPFM) provides information on polaron dynamics that is compared to kinetic Monte Carlo (KMC) simulations.