%0 Journal Article
%A Cerc Korošec, Romana
%A Umek, Polona
%A Gloter, Alexandre
%A Padežnik Gomilšek, Jana
%A Bukovec, Peter
%T Structural properties and thermal stability of cobalt- and chromium-doped α−MnO<sub>2</sub> nanorods
%J Beilstein journal of nanotechnology
%V 8
%@ 2190-4286
%C Frankfurt, M.
%I Beilstein-Institut zur Förderung der Chemischen Wissenschaften
%M PUBDB-2017-09669
%P 1032 - 1042
%D 2017
%X α-MnO<sub>2</sub>  nanorods were synthesized via the hydrothermal decomposition of KMnO<sub>4</sub> in an acidic environment in the presence of Co<sup>2+</sup> and Cr<sup>3+</sup> ions. Reactions were carried out at three different temperatures: 90, 130 and 170 °C. All prepared samples exhibit a tetragonal MnO<sub>2</sub> crystalline phase. SEM–EDS analysis shows that cobalt cations are incorporated to a higher degree into the MnO<sub>2</sub> framework than chromium ions, and that the content of the dopant ions decreases with increasing reaction temperature. The oxidation of Co<sup>2+</sup> to Co<sup>3+</sup> during the reaction was proved by an XANES study, while EXAFS results confirm that both dopant ions substitute Mn<sup>4+</sup> in the center of an octahedron. The K/Mn ratio in the doped samples synthesized at 170 °C is significantly lower than in the undoped samples. Analysis of an individual cobalt-doped α-MnO<sub>2</sub>  nanorod with HAADF-STEM reveals that the distribution of cobalt through the cross-section of the nanorod is uniform. The course of thermal decomposition of the doped nanorods is similar to that of the undoped ones. Dopant ions do not preserve the MnO<sub>2</sub> phase at higher temperatures nor do they destabilize the cryptomelane structure.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000406241500001
%$ pmid:28546897
%R 10.3762/bjnano.8.104
%U https://bib-pubdb1.desy.de/record/390612