2020/04/24 by Nandhini J. Usharani, Anikesh Bhandarkar, Usharani, Nandhini J. +5 · 1 citation
Engineering · #FOS: Physical sciences #High Entropy Alloys Studies #High-Temperature Coating Behaviors #Laser-Ablation Synthesis of Nanoparticles #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.2004.11684
openalex publication_date 2020/04/24 · openalex created_date 2022/07/23 · openalex updated_date 2026/07/28
For the first time, this study shows that distortion in a crystal structure\ndue to magnetic effect is possible in a lattice with extreme chemical disorder.\nThe multicomponent equimolar transition metal oxide (ME TMO),\n(Co,Cu,Mg,Ni,Zn)O, which is a high entropy oxide, has been attracting a lot of\nattention due to its unique application potential in many fields including\nelectrochemical energy storage. In the present investigation, nanocrystalline\nME TMO was synthesised by three bottom up methods. The presence of distortion\nin the rocksalt crystal structure, revealed by X ray diffraction and Raman\nspectroscopy, and correlated with magnetic measurements from SQUID and EPR\nstudies could be attributed to the additive effects of exchange striction (from\nthe magnetic constituents) and magnetic anisotropy (from the decreased\ncrystallite size). For the first time, iron has been doped into ME TMO, to show\nthat a higher amount of magnetic constituent increases the distortion in the\nlattice. Nanocrystalline ME TMO also showed a core shell magnetic behavior\nbelow the bifurcation temperature arising from the uncompensated or canted spin\nat the surface. Neel temperature of the nanocrystalline ME TMO is reported for\nfirst time to be as high as 700 K. This study helps unravel the structure and\nmagnetic properties of such high entropy materials, and augurs a definite scope\nfor better understanding of the factors influencing the crystal structure in\nhigh entropy oxides.\n