2013/01/01 by Paul C. Snijders, Min Gao, Hangwen Guo +7
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Catalysis #Chemical physics #Chemistry #Condensed matter physics #Electronic and Structural Properties of Oxides #Epitaxy #Ferromagnetism #Layer (electronics) #Magnetic and transport properties of perovskites and related materials #Manganite #Materials science #Metallurgy #Nanotechnology #Oxide #Oxygen #Physical chemistry #Stoichiometry #Thin film #Transition metal #cond-mat.mtrl-sci
paper · pdf · doi:10.1039/c3nr02343e
published as Nanoscale 5, 9659 (2013)
openalex publication_date 2013/01/01 · arxiv created 2014/01/28 · arxiv updated 2014/01/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The oxygen stoichiometry has a large influence on the physical and chemical properties of complex oxides. Most of the functionality in e.g. catalysis and electrochemistry depends in particular on control of the oxygen stoichiometry. In order to understand the fundamental properties of intrinsic surfaces of oxygen-deficient complex oxides, we report on in situ temperature dependent scanning tunnelling spectroscopy experiments on pristine oxygen deficient, epitaxial manganite films. Although these films are insulating in subsequent ex situ in-plane electronic transport experiments at all temperatures, in situ scanning tunnelling spectroscopic data reveal that the surface of these films exhibits a metal-insulator transition (MIT) at 120 K, coincident with the onset of ferromagnetic ordering of small clusters in the bulk of the oxygen-deficient film. The surprising proximity of the surface MIT transition temperature of nonstoichiometric films with that of the fully oxygenated bulk suggests that the electronic properties in the surface region are not significantly affected by oxygen deficiency in the bulk. This carries important implications for the understanding and functional design of complex oxides and their interfaces with specific electronic properties in catalysis, oxide electronics and electrochemistry.