Journal Article

IMPULSE-2025-00081

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Understanding the Role of Hydrogen and Oxygen in Electronic Phase Changes of Nickelates

Guasco, L.MLZ* ; Pons, R. ; Cortie, D. ; Bannenberg, L. J. ; Wochner, P. ; Goering, E. ; Nagel, P. ; Schuppler, S. ; Hayashida, S. ; Merkle, R. ; Keimer, B. ; Keller, T.MLZ* ; Benckiser, E.

2025
Wiley-VCH Weinheim

Please use a persistent id in citations: doi:10.1002/adfm.202419253

Abstract: Many electronic and electrochemical devices rely on the exchange of light elements such as hydrogen and oxygen with the environment. Understanding and tailoring the device functionality requires accurate information about the concentration and chemical bonding of such species inside a solid, which is particularly difficult if several species are exchanged. In LaNiO3 thin films in situ transport experiments reveal a re-entrant metal–insulator transition upon hydrogen exposure. The origin of this unusual behavior can be understood by combining information about the stoichiometry and chemical bonding of hydrogen and oxygen as determined by neutron reflectometry and x-ray absorption spectroscopy, respectively. In addition to the metallic parent phase, an insulating phase with composition LaNiO2.65 and a re-entrant metallic phase with composition LaNiO2.15(OH)0.5 are identified. They can be inter-converted by redox reactions in different external environments. The methodology employed offers new insights into the mechanisms underlying the influence of hydrogen in functional devices.

Keyword(s): Engineering, Industrial Materials and Processing (1st) ; Condensed Matter Physics (2nd) ; Materials Science (2nd)

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Contributing Institute(s):

1. NREX (NREX)

Experiment(s):

1. NREX: Neutron reflectometer with X-ray option (NL1)

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Electronics and Telecommunications Collection ; Current Contents - Engineering, Computing and Technology ; Current Contents - Physical, Chemical and Earth Sciences ; DEAL Wiley ; Ebsco Academic Search ; Essential Science Indicators ; IF >= 15 ; JCR ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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