Effect of vanadium doping on structural and magnetic properties of defective nano-nickel ferrite

This paper describes the composition-dependent microstructural, magnetic and dielectric properties of vanadium ions doped nickel ferrite nanoparticles. All the nanoferrite samples (NiV x Fe 2-x O 4 : x = 0.00, 0.05, 0.10 and 0.15) were prepared using conventional co-precipitation method. X-ray diffraction patterns verified the single cubic spinel phase formation and achievement of nano-sized ferrite particles with a homogeneous distribution, which was also supported by HRTEM micrographs. Mean crystallite diameter was seen in the range of 05 nm to 12 nm as evaluated from Williamson-Hall (W-H) curves for the different doped samples. A compressive nature microstrain was noticed in all the samples and was also seen to reduce with the enhancement of vanadium ions content. A blue shift was detected in the indirect band gap for higher vanadium doped samples. Magnetization at the saturation point as well as coercive field both were observed to reduce at room temperature with increasing vanadium concentration in nanosized nickel ferrites. Room temperature dielectric characteristics of all the synthesized samples ensured that the elementary charge conduction process was governed by the hopping of electrons. Cole-Cole plots also showed that the grain boundaries play an important task in deciding the dielectric responses.

Section: Magnetic Studiesmentioning

confidence: 61%

“…Paramagnetic vanadium (V 3+ ) ions have been selected as the dopant. Few articles on vanadium doped spinel ferrite nanoparticles were reported till now [15,16]. Most of the researchers were unable to prepare impurities free spinel ferrite samples [17].…”

Section: Introductionmentioning

confidence: 99%

Tailoring the microstructural, magnetic and dielectric properties of vanadium ions substituted nickel ferrite nanocrystals

Tanbir

Ghosh

Kar

et al. 2021

“…The four weak bands have been explained as follows. Bands ν3 and ν4 at ~820 cm −1 and 865 cm −1 correspond to Fe 4+ [51,52] and Ni 3+ [53,44] bonds, respectively. The absorption bands ν5 and ν6 at 950 and 980 cm 1 probably originate from Ni 4+  and Co 4+ oxygen bonds.…”

Section: Structural Propertiesmentioning

confidence: 99%

The impact of cation distribution on the structural and magnetic properties of nonstoichiometric Co0.5Ni0.5+xFe2−xO4 nanoferrites

Wahba

Moharam

Mahmoud

2021

Self Cite

In this work, the impact of nonstoichiometric substitution of Fe 3+ cations by Ni 2+ ones on the structural and magnetic properties of Co0.5Ni0.5+xFe2xO4 (0.0 ≤ x ≤ 0.4) nanoferrites synthesized by citric autocombustion method. The cubic phase purity for sintered samples were verified by XRD patterns and FTIR spectra. The crystallite size and microstrain were deduced using Williamson-Hall method. The estimated crystallite size ranges from 55 to 89 nm in agreement with TEM microimages. Hysteresis loops traced using VSM prevailed a regular reduction of saturation magnetization with Ni substitution. Relied on the experimental data of XRD, FTIR, and VSM, cation distribution has been suggested, according to which the nonstoichiometric substitution was compensated by the appearance of higher valance states of Fe, Ni, and Co cations. The suggested cation distribution successfully explained the recorded data of lattice parameter, crystallite size, IR frequencies, magnetization and coercivity.

“…Doping can change the lattice constant and also induce some structural defects in the host material. In this context, addition of V element in the nickel ferrite has been reported to be a good strategy to enhance properties of resultant V-doped ferrite [8]. In addition, the NiFe 2 O 4 has a low electrical conductivity which can be tuned with the help of charge exchanging behaviour between multiple valence states of V ion at equivalent lattice sites [9].…”

Section: Introductionmentioning

confidence: 99%

Effect of Vd-doping on dielectric, magnetic and gas sensing properties of nickel ferrite nanoparticles

Manikandan¹,

Petrila

Kavita

et al. 2020

Pristine and vanadium-doped nickel ferrite (NiFe 2 O 4 ) nanoparticles (NPs) were prepared by a chemical co-precipitation method. They were characterized by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy to explore their crystallinity, morphology and chemical states. Dielectric constant and dielectric loss properties were studied as a function of frequency and temperature and it was found that V-doping resulted in the enhancement of the dielectric properties. Both pristine and V-doped ferrites showed superparamagnetic nature and zero coercivity and retentivity. However, the saturation magnetization was decreased after V-doping, suggesting presence of superexchange interaction between A-B sites. Both pristine and V-doped NiFe 2 O 4 NPs were also used for NO sensing studies and it was revealed that V-doped gas sensor revealed a better sensing performance (response of 5 s and sensitivity of 43 to 200 ppm NO gas) than pristine one (response of 9 s and sensitivity of 37 to 200 ppm NO gas).