Electrochemical Tuning of Magnetism in Nanoporous Systems - Oxidation, Hydrogenation and Surface Charging

Markus Gößler, Eva-Maria Steyskal, Heinz Krenn, Jörg Weißmüller, Lukas Lührs, Roland Würschum

Research output: Contribution to conferenceAbstract

Abstract

Nanoporous materials have attracted considerable interest in the scientific community as functional materials with a broad variety of applications, including catalysis and sensing. Owed to their high surface-to-volume ratios it is possible to alter bulk properties via surface modifications.

Electrochemical reactions represent a versatile method to achieve defined surface states with controlled chemical composition and charging state. Magnetic properties of metals and alloys are highly sensitive to both chemical environment and electronic structure, which motivated our investigations.

Metal and alloy electrodes were prepared via electrochemical dealloying, a selective dissolution process from binary or ternary alloys, respectively. By exposing the precursor to an etching agent, the least noble component of the alloy is gradually removed, while enhancing the surface diffusivity of the more noble compound(s) [1]. Appropriate processing conditions enable the formation of nanoporous structures, with the main benefit being adjustable pore sizes. Nanoporous palladium (npPd) and nanoporous copper-nickel alloys (npCuNi) were used as model systems, amongst other promising candidates.

Magnetic tuning experiments were performed in an electrochemical cell, designed for special use in a SQUID (Superconducting Quantum Interference Device) magnetometer. This enables sensitive in situ measurements of the changes in magnetic moment upon various electrochemical treatments and a direct assignment of chemical reactions to magnetic behaviour [2].

Alterations of the magnetic moment of more than 20% were measured for npCuNi upon surface oxidation in aqueous electrolyte, which will be discussed in terms of a perturbation of the magnetic order of the nickel atoms. Furthermore, changes in magnetisation upon surface charging and hydrogenation of npPd are presented.

This work is financially supported by the Austrian Science Fund (FWF): P30070-N36.

[1] I. McCue et al., Ann. Rev. Mater. Res. 46 (2016) 263
[2] E.-M. Steyskal et al., Beilst. J. Nanotech. 4 (2013) 394

Original languageEnglish
Publication statusPublished - 2018
Event68th Annual Meeting of the Austrian Physical Society - Technische Universität Graz, Graz, Austria
Duration: 11 Sep 201814 Sep 2018
Conference number: 68
https://www.tugraz.at/events/oepg2018/home/

Conference

Conference68th Annual Meeting of the Austrian Physical Society
Abbreviated titleÖPG
CountryAustria
CityGraz
Period11/09/1814/09/18
Internet address

Fields of Expertise

  • Advanced Materials Science

Fingerprint Dive into the research topics of 'Electrochemical Tuning of Magnetism in Nanoporous Systems - Oxidation, Hydrogenation and Surface Charging'. Together they form a unique fingerprint.

  • Projects

    Activities

    • 1 Talk at conference or symposium

    Electrochemical Tuning of Magnetism in Nanoporous Systems - Oxidation, Hydrogenation and Surface Charging

    Markus Gößler (Speaker), Eva-Maria Steyskal (Contributor), Heinz Krenn (Contributor), Lukas Lührs (Contributor), Jörg Weißmüller (Contributor), Roland Würschum (Contributor)
    11 Sep 2018

    Activity: Talk or presentationTalk at conference or symposiumScience to science

    Cite this

    Gößler, M., Steyskal, E-M., Krenn, H., Weißmüller, J., Lührs, L., & Würschum, R. (2018). Electrochemical Tuning of Magnetism in Nanoporous Systems - Oxidation, Hydrogenation and Surface Charging. Abstract from 68th Annual Meeting of the Austrian Physical Society, Graz, Austria.