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arXiv · 1708.09255

Nanoscale X-ray investigation of magnetic metallofullerene peapods

Fabian Fritz·Rasmus Westerström·Aram Kostanyan·Christin Schlesier·Jan Dreiser·Benjamin Watts·Lothar Houben·Martina Luysberg·Stanislav M Avdoshenko·Alexey A Popov·Claus M Schneider·Carola Meyer
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Abstract

Endohedral lanthanide ions packed inside carbon nanotubes (CNTs) in a one-dimensional assembly have been studied with a combination of high resolution transmission electron microscopy (HRTEM), scanning transmission X-ray microscopy (STXM), and X-ray magnetic circular dichroism (XMCD). By correlating HRTEM and STXM images we show that structures down to 30 nm are resolved with chemical contrast and record X-ray absorption spectra from endohedral lanthanide ions embedded in individual nanoscale CNT bundles. XMCD measurements of an Er$_3$N@C$_{80}$ bulk sample and a macroscopic assembly of filled CNTs indicates that the magnetic properties of the endohedral Er3+ ions are unchanged when encapsulated in CNTs. This study demonstrates the feasibility of local magnetic X-ray characterization of low concentrations of lanthanide ions embedded in molecular nanostructures.

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Fabian Fritz, Rasmus Westerström, Aram Kostanyan, Christin Schlesier, Jan Dreiser, Benjamin Watts, Lothar Houben, Martina Luysberg, Stanislav M Avdoshenko, Alexey A Popov, Claus M Schneider, Carola Meyer. 2017-08-30. Nanoscale X-ray investigation of magnetic metallofullerene peapods. https://doi.org/10.1088/1361-6528/aa8b4c

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