TU Darmstadt / ULB / TUbiblio

Magnetic, magnetocaloric and structural properties of manganese based monoborides doped with iron and cobalt – A candidate for thermomagnetic generators

Fries, Maximilian and Gercsi, Zsolt and Ener, Semih and Skokov, Konstantin P. and Gutfleisch, Oliver (2016):
Magnetic, magnetocaloric and structural properties of manganese based monoborides doped with iron and cobalt – A candidate for thermomagnetic generators.
In: Acta Materialia, Elsevier Science Publishing, pp. 213-220, 113, ISSN 13596454,
[Online-Edition: http://dx.doi.org/10.1016/j.actamat.2016.05.005],
[Article]

Abstract

Refractory borides are good candidates for thermomagnetic energy conversion due to their high chemical stability and good magnetic properties. A systematic study focusing on the crystallographic, magnetic and magnetocaloric properties of cobalt and iron substituted MnB was conducted. The pure MnB sample shows an orthorhombic structure with a spontaneous magnetization (Ms) of 156 Am2kg−1 and a sharp magnetic transition (TC) of 567 K that yields a large magnetic entropy change of 7.5 J kg−1K−1 in a 2T field change at this temperature. Both the substitution of Co and Fe elements for Mn were found to effectively modify TC accompanied by a lower magnetization (Ms) leading to a reduced magnetocaloric effect (MCE). The differences in magnetic properties with substitution are described by calculation of the density of states and interatomic distances. It is found that in contrast to the Co atoms the Fe atoms develop large and stable moments similar to the Mn atoms which is consistent with the experimental findings. The sharp and significant change of Ms(T), the very stable nature of these refractory borides and abundant availability makes some of these compositions suitable for thermomagnetic power generation applications.

Item Type: Article
Erschienen: 2016
Creators: Fries, Maximilian and Gercsi, Zsolt and Ener, Semih and Skokov, Konstantin P. and Gutfleisch, Oliver
Title: Magnetic, magnetocaloric and structural properties of manganese based monoborides doped with iron and cobalt – A candidate for thermomagnetic generators
Language: English
Abstract:

Refractory borides are good candidates for thermomagnetic energy conversion due to their high chemical stability and good magnetic properties. A systematic study focusing on the crystallographic, magnetic and magnetocaloric properties of cobalt and iron substituted MnB was conducted. The pure MnB sample shows an orthorhombic structure with a spontaneous magnetization (Ms) of 156 Am2kg−1 and a sharp magnetic transition (TC) of 567 K that yields a large magnetic entropy change of 7.5 J kg−1K−1 in a 2T field change at this temperature. Both the substitution of Co and Fe elements for Mn were found to effectively modify TC accompanied by a lower magnetization (Ms) leading to a reduced magnetocaloric effect (MCE). The differences in magnetic properties with substitution are described by calculation of the density of states and interatomic distances. It is found that in contrast to the Co atoms the Fe atoms develop large and stable moments similar to the Mn atoms which is consistent with the experimental findings. The sharp and significant change of Ms(T), the very stable nature of these refractory borides and abundant availability makes some of these compositions suitable for thermomagnetic power generation applications.

Journal or Publication Title: Acta Materialia
Volume: 113
Publisher: Elsevier Science Publishing
Uncontrolled Keywords: Borides, Transition metals, Magnetic properties, DFT, Thermomagnetic generator
Divisions: 11 Department of Materials and Earth Sciences > Material Science > Functional Materials
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences
Date Deposited: 08 Jul 2016 11:20
Official URL: http://dx.doi.org/10.1016/j.actamat.2016.05.005
Identification Number: doi:10.1016/j.actamat.2016.05.005
Funders: Part of this research has received funding from the European Communitys Seventh Framework Programme FP7/2007–2013 under grant agreement number 310748 (DRREAM)., The DFG (Grant No. SPP 1599) is also acknowledged for financial support., The support from the German federal state of Hessen through its excellence programme LOEWE “RESPONSE” is acknowledged., Z. G. acknowledges the financial support from a Marie Curie Intra European Fellowship within the 7th European Community Framework Programme., Computing resources provided by Darwin HPC and Camgrid facilities at The University of Cambridge and the HPC Service at Imperial College London are gratefully acknowledged.
Export:
Suche nach Titel in: TUfind oder in Google

Optionen (nur für Redakteure)

View Item View Item