Electrochemical stability of (La,Sr)CoO3−δ in (La,Sr)CoO3−δ/(Ce, Gd)O2−δ heterostructures

• Published in: Nanoscale Vol. 11; no. 6; pp. 2916 - 2924
• Main Authors: Lucía dos Santos-Gómez, Sanna, Simone, Norby, Poul, Pryds, Nini, Losilla, Enrique R, Marrero-López, David, Esposito, Vincenzo
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 14.02.2019
• Subjects: Chemical properties; Confining; Crystal structure; Electrical properties; Electrical resistivity; Electronic properties; Gadolinium; Heterostructures; Lanthanum; Multilayers; Organic chemistry; Pulsed laser deposition; Pulsed lasers; Single crystals; Stability; Substrates; Thin films
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/c8nr08528e

A modulated coherent (La,Sr)CoO3−δ/(Ce,Gd)O2−δ heterostructure is characterized for the first time for its electronic and chemical properties. 2D-multilayer architectures are deposited on NdGaO3 (110) single crystal substrate by pulsed laser deposition, resulting in epitaxial structures with in-plane lattice rotation that, via the metal oxides’ interfaces, induces mutual structural rearrangements. Our results show that (La,Sr)CoO3−d thin films of 10–100 nm are chemically unstable when exposed to air at 600 °C during electrical cyclic stress-tests. Conversely, improved stability is achieved confining LSC in the nanometric heterostructure. Remarkably, the chemical stabilization occurs without compromising substantially the electrical properties of the LSC component: the heterostructures show unexpected electrical behaviour with dominant electronic contributions, fast conductivity and mixed ionic-electronic properties, depending on the number of interfaces and the nano-scaled layers.