Next Article in Journal
Water Structures and Packing Efficiency in Methylene Blue Cyanometallate Salts
Previous Article in Journal
Local Vibrational Mode Analysis of π–Hole Interactions between Aryl Donors and Small Molecule Acceptors
Open AccessArticle

Oxygen Inhomogeneity and Reversibility in Single Crystal LaNiO3−δ

1
Materials Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
2
Institute of Crystal Materials, Shandong University, Jinan, Shandong 250100, China
3
Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA
*
Author to whom correspondence should be addressed.
Crystals 2020, 10(7), 557; https://doi.org/10.3390/cryst10070557
Received: 19 May 2020 / Revised: 8 June 2020 / Accepted: 14 June 2020 / Published: 30 June 2020
(This article belongs to the Special Issue Single Crystal Growth of Metal Oxides)
LaNiO3−δ single crystals have been obtained via high pressure floating zone growth under 149 bar of oxygen pressure. We find a radial gradient in the magnetic properties of specimens extracted from the as-grown boule, which we correlate with the appearance of ordered oxygen vacancy structures. This radial oxygen inhomogeneity has been characterized systematically using a combination of magnetization and X-ray scattering measurements. We establish the presence of rhombohedral ( R 3 ¯ c ), oxygen stoichiometric specimens at the periphery of the boule and the presence of a dilute concentration of ordered oxygen-deficient orthorhombic La2Ni2O5 in the center. Furthermore, we demonstrate that the as-grown, oxygen-deficient central regions of the crystal can be annealed under high oxygen pressure, without loss of crystallinity, into fully oxygenated LaNiO3, recovering magnetic properties that are characteristic of stoichiometric specimens from the exterior region of the crystal. Thus, single crystals of LaNiO3−δ possess oxygen content that can be reversibly modified under oxidizing and reducing conditions. View Full-Text
Keywords: nickelates; crystal growth; oxygen deficiency; diffraction nickelates; crystal growth; oxygen deficiency; diffraction
Show Figures

Figure 1

MDPI and ACS Style

Zheng, H.; Wang, B.-X.; Phelan, D.; Zhang, J.; Ren, Y.; Krogstad, M.J.; Rosenkranz, S.; Osborn, R.; Mitchell, J.F. Oxygen Inhomogeneity and Reversibility in Single Crystal LaNiO3−δ. Crystals 2020, 10, 557.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop