Effect of Cu substitution on magnetic and DC electrical resistivity properties of Ni–Zn nanoferrites

Author(s):  
K. Chandramouli ◽  
P. Anantha Rao ◽  
B. Suryanarayana ◽  
Vemuri Raghavendra ◽  
Shaik Jesus Mercy ◽  
...  
2021 ◽  
Vol 127 (5) ◽  
Author(s):  
P. Himakar ◽  
K. Jayadev ◽  
D. Parajuli ◽  
N. Murali ◽  
Paulos Taddesse ◽  
...  

2018 ◽  
Vol 16 (38) ◽  
Author(s):  
Amal K. Jassim

Samples of Bi1.6Pb0.4Sr2Ca2Cu3O10+δ superconductor were prepared by solid-state reaction method to study the effects of gold nanoparticles addition to the superconducting system, Nano-Au was introduced by small weight percentages (0.25, 0.50, 0.75, 1.0, and 1.25 weight %). Phase identification and microstructuralcharacterization of the samples were investigated using XRD and SEM. Moreover, DC electrical resistivity as a function of the temperature, critical current density Jc, AC magnetic susceptibility, and DC magnetization measurements were carried to evaluate the relative performance of samples. x-ray diffraction analysis showed that both (Bi,Pb)-2223 and Bi-2212 phases coexist in the samples having an orthorhombic crystal structure. Both the onset critical temperatures Tc (onset) and zero electrical resistivity critical temperatures Tc (R=0) of the samples were determined from the DC electrical resistivity measurements. An improvement of the superconducting transition temperature of 6.36 % was obtained with increasing Au nanoparticles to x = 1.25 wt.%, while the critical current density is improved by 220 %. AC magnetic susceptibility measurement showed that the diamagnetic fraction and intergranular coupling of the x = 1.25 wt.% sample are greater than those of the others. The variation of magnetization with temperature (M-T curve) of the samples was measured by cooling the sample in zero fields (ZFC) and an applied field of 10 Oe (FC). The results of AC magnetic susceptibility and DC magnetization measurements were in good agreement with DC electrical resistivity measurement.


2011 ◽  
Vol 323 (16) ◽  
pp. 2115-2121 ◽  
Author(s):  
M. Siva Ram Prasad ◽  
B.B.V.S.V. Prasad ◽  
B. Rajesh ◽  
K.H. Rao ◽  
K.V. Ramesh

2018 ◽  
Vol 29 (11) ◽  
pp. 2601-2607 ◽  
Author(s):  
A. Ramakrishna ◽  
N. Murali ◽  
S.J. Margarette ◽  
Tulu Wegayehu Mammo ◽  
N. Krishna Joythi ◽  
...  

2009 ◽  
Vol 92 (10) ◽  
pp. 2425-2428 ◽  
Author(s):  
Prita Pant Sarangi ◽  
Sampat Raj Vadera ◽  
Manoj Kumar Patra ◽  
Chandra Prakash ◽  
Narendra Nath Ghosh

1988 ◽  
Vol 21 (2) ◽  
pp. 378-381 ◽  
Author(s):  
J A Veira ◽  
J Maza ◽  
F Miguelez ◽  
J J Ponte ◽  
C Torron ◽  
...  

2011 ◽  
Vol 34 (6) ◽  
pp. 103763
Author(s):  
L. D. Suits ◽  
T. C. Sheahan ◽  
Yves-Laurent Beck ◽  
Sérgio Palma Lopes ◽  
Valéry Ferber ◽  
...  

2013 ◽  
Vol 202 ◽  
pp. 173-192 ◽  
Author(s):  
Sonal Singhal ◽  
Santosh Bhukal

Nano-crystalline Co0.6Zn0.4Cu0.2CrxFe1.8-xO4 (x = 0.2, 0.4, 0.6 and 0.8), have been synthesized using a citrate sol-gel auto combustion method and annealed at different temperature 400 °C, 600 °C, 800 °C and 1000 °C. The effect of chromium substitution on the structural, magnetic and dielectric properties of cobalt-zinc-copper ferrite has been studied. The structural and magnetic characteristics have been studied by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and Vibrating Sample Magnetometer (VSM) techniques. The X-ray diffractogram of all the annealed samples confirm the formation of single phase with Fd-3m space group. The crystalline sizes have been found to increase (from ~15 nm – to 60 nm) with the annealing temperature. The DC electrical resistivity of all the ferrites has been measured using a two-probe method between temperature range of 30 °C to 100 °C. The DC electrical resistivity of all the samples decrease with increase in temperature indicates semiconducting nature. However, the DC resistivity increase as the Cr3+ concentration increases because the Cr3+ ions enter the octahedral sites and reduce the electron exchange between Fe2+ and Fe3+ causing a decrease in polaron hopping of Fe2+-Fe3+ions. The value of the Seebeck coefficient (S) for all the ferrites is found to be positive indicating that all the ferrite samples behave as p-type semiconductors. The effect of copper chromium cation distribution among the tetrahedral (A) and octahedral (B) sites of Co-Zn substituted ferrite on magnetization and coercivity field have been investigated using VSM (vibrating sample magnetometer) technique. The decrease in the saturation magnetization (Ms) with increasing chromium content may be attributed to the copper and chromium enters into the octahedral site of the Co-Zn ferrite.


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