Apparent Oxygen Uphill Diffusion in La0.8Sr0.2MnO3 Thin Films upon Cathodic Polarization

• DOI: 10.1002/celc.201500167
• Publication Date: 2015-07-24T14:56:52Z
• Authors: Tobias M. Huber; Edvinas Navickas; Gernot Friedbacher; Herbert Hutter; Jürgen Fleig
• Keywords: Stoichiometry; Rutherford backscattering spectrometry; Biasing

Abstract The impact of cathodic bias on oxygen transport in La 0.8 Sr 0.2 MnO 3 (LSM) thin films was investigated. Columnar‐grown LSM with different microstructures were deposited by pulsed laser deposition. 18 O tracer experiments performed film microelectrodes an applied −300 or −450 mV, and the subsequently analyzed time‐of‐flight secondary ion mass spectrometry. concentration cathodically polarized strongly increased relative to that thermally annealed (without bias). Most remarkable, however, appearance a pronounced fraction maximum center films. This depended microstructure layers. unusual shape depth profiles caused combination Wagner–Hebb‐type stoichiometry polarization bulk, fast grain boundary voltage‐induced modification incorporation kinetics,