Authors: P.R. Koushalya; K.N. Anuradha
Addresses: Department of Physics, Don Bosco Institute of Technology, Bangalore, 560074, India ' Department of Physics, Dr. Ambedkar Institute of Technology, Bangalore, 560056, India
Abstract: In this paper, we study the enhanced grain surface effect on the magnetic properties of Pr0.57Ca0.43MnO3 (PCMO) nanomanganites. Nanoparticles OF PCMO were prepared by low cost sol-gel route and bulk sample was prepared by solid state reaction method. Crystallite size and structure of the samples were studied by X-ray diffraction (XRD) method. Surface morphology and compositional analysis were studied by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). Magnetisation measurements were carried out using superconducting quantum interference magnetometer (SQUID) in the temperature range of 10-300 K. The temperature dependence of field cooled magnetisation of bulk sample show charge order (CO) peak around 240 K and antiferromagnetic (AFM) transition at 170 K. Interestingly the charge order peak was found to be absent in 17 nm and 21 nm particles and both samples show ferromagnetic (FM) transition (TC) at 60 K and 90 K respectively. Melting of charge order and appearance of ferromagnetism in PCMO nanoparticles will be discussed with the help of core-shell model.
Keywords: charge order; nanomanganite; nanoparticles; core shell.
International Journal of Nanotechnology, 2017 Vol.14 No.9/10/11, pp.907 - 914
Received: 08 May 2021
Accepted: 12 May 2021
Published online: 25 Jun 2017 *