Structural, optical and electrical properties of Mn-doped ZnFe2O4 synthesized using sol-gel method

Abstract Samples with doping of Mn (0, 2, and 4%) in ZnFe2O4 were prepared by sol-gel chemical route at 80oC. X-ray powder diffraction and Raman spectrum analysis were used to determine the preliminary phase of obtained samples. W-H and SSP plots were used to determine the crystallite size and micro-strain of samples. Using zeta potential and scanning electron microscope, the surface charge and morphology of the prepared samples were studied. The optical bandgap of sample suggested that it was semiconducting. The dielectric characteristics of samples were examined as a function of temperature at various frequencies (1 KHz, 10 KHz, 100 KHz, and 1 MHz) (60-600oC). Dielectric study revealed the presence of interfacial and orientational polarization, with dielectric constants and dissipation factors ranging from (0.7–460) to (0.3–0.8), remain thermally stability up to 300oC. In samples ZF-0, ZF-2, and ZF-4, the thermal dependence of DC conductivity demonstrates Arrhenius transport with one, two, and three regions of conduction, respectively. The sources of charge carrier in samples were Vo,e1 defects (Vo - 2FE2+ Fe3+') and (2M3+ Zn2+ - 2FE2+ Fe3+'). The current work could help identify possible applications in semiconductor devices, thermally stable capacitors, and as mixed ionic electronic conductors in solid oxide fuel cells.

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Dielectric Properties of A, B-Site Mn-Doped LaTiO3+δ

Materials Science Forum ◽

10.4028/www.scientific.net/msf.921.78 ◽

2018 ◽

Vol 921 ◽

pp. 78-84

Author(s):

Yan Chen ◽

Qi Qi Yan ◽

Yi Min Cui

Keyword(s):

Dielectric Properties ◽

Dielectric Response ◽

Low Frequency ◽

Solid State Reaction Method ◽

Dielectric Constants ◽

Conventional Solid State Reaction ◽

Dielectric Characteristics ◽

Low Dielectric ◽

A Site ◽

Mn Doped

A-site Mn-doped La1-xMnxTiO3+δand B-site doped LaMnxTi1-xO3+δ(x = 0.1, 0.2) composites were synthesized by conventional solid-state reaction method. The low-frequency complex dielectric properties of the composites were investigated as functions of temperature (77 K ≤ T ≤ 360 K) and frequency (100 Hz ≤ f ≤ 1 MHz), respectively. The dielectric constants of A-site doped samples are higher than that of B-site doped samples. The loss tangents of the low doped samples are much less than that of the high doped samples. The A-site doped composites exhibit intrinsic dielectric response with a dielectric constant of ~40 in the temperature below 250 K. Interestingly, the dielectric constants of B-site doped composites always increased in the temperature range from 77 to 360 K. And it is clearly observed that extraordinarily low dielectric loss tangents appear in LaMn0.1Ti0.9O3+δ, which are much lower than that of LaMn0.2Ti0.8O3+δ. These changes indicate that the doped content can affect the intrinsic dielectric characteristics significantly.

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Electron microscopy studies of PZT ferroelectric film capacitor structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131450 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1364-1365

Author(s):

V. Kaushik ◽

P. Maniar ◽

J. Olowolafe ◽

R. Jones ◽

A. Campbell ◽

...

Keyword(s):

Electric Fields ◽

Sol Gel ◽

Ferroelectric Material ◽

Dielectric Constants ◽

Dielectric Films ◽

Lead Zirconium Titanate ◽

Si Substrate ◽

Film Capacitor ◽

Pzt Films ◽

High Dielectric

Lead zirconium titanate films (Pb (Zr,Ti) O3 or PZT) are being considered for potential application as dielectric films in memory technology due to their high dielectric constants. PZT is a ferroelectric material which shows spontaneous polarizability, reversible under applied electric fields. We report herein some results of TEM studies on thin film capacitor structures containing PZT films with platinum-titanium electrodes.The wafers had a stacked structure consisting of PZT/Pt/Ti/SiO2/Si substrate as shown in Figure 1. Platinum acts as electrode material and titanium is used to overcome the problem of platinum adhesion to the oxide layer. The PZT (0/20/80) films were deposited using a sol-gel method and the structure was annealed at 650°C and 800°C for 30 min in an oxygen ambient. XTEM imaging was done at 200KV with the electron beam parallel to <110> zone axis of silicon.Figure 2 shows the PZT and Pt layers only, since the structure had a tendency to peel off at the Ti-Pt interface during TEM sample preparation.

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Structural and Magnetic Behavior of Mn Doped Zno Synthesized By Soft Chemical Route

International Journal of Innovative Research in Science Engineering and Technology ◽

10.15680/ijirset.2014.0311008 ◽

2014 ◽

Vol 03 (11) ◽

pp. 17150-17153

Author(s):

Dr. Lata V. Bhandarkar

Keyword(s):

Magnetic Behavior ◽

Chemical Route ◽

Doped Zno ◽

Mn Doped ◽

Soft Chemical Route

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Green Synthesis of Cobalt Oxide Nanoparticles by a Starch-Assisted Method

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681208666180312123055 ◽

2019 ◽

Vol 9 (3) ◽

pp. 362-370 ◽

Cited By ~ 1

Author(s):

D. Vaya ◽

Meena ◽

B.K. Das

Keyword(s):

Photocatalytic Activity ◽

Cobalt Oxide ◽

Sol Gel ◽

Complex Nature ◽

Oxide Nanoparticles ◽

Capping Agent ◽

Chemical Route ◽

Gel Method ◽

Sol Gel Method ◽

Cobalt Oxide Nanoparticles

Background: The properties of the material are altered when material size shifted towards nano-regime. This feature could be used for wastewater treatment process using model pollutant such as dyes. Recently, nanoparticles are synthesized by a green chemical route using different capping agents. This is the reason we adopt starch as green capping agent along with sol-gel method. Objective: To synthesize cobalt oxide nanoparticles by green chemical route and utilized it in degradation of dyes. Methods: Synthesis of cobalt oxide nanoparticles by sol-gel method using starch as a capping agent. The characteristics of surface modifications were investigated by UV-VIS, TEM, SEM, XRD and FTIR techniques. Results: Cobalt oxide nanoparticles synthesized and inhibited photocatalytic activity. Conclusion: Deactivation of photocatalytic activity due to complex nature of starch. This property can be used elsewhere as in light shielding applications to coat and protect surfaces in order to keep them cool and safe from damage as in the painting of vehicles, roofs, buildings, water tanks, etc.

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Valence state and magnetism of Mn-doped PbPdO 2 nanograin film synthesized by sol-gel spin-coating method

Thin Solid Films ◽

10.1016/j.tsf.2016.12.043 ◽

2017 ◽

Vol 623 ◽

pp. 14-18 ◽

Cited By ~ 6

Author(s):

Fenglin Tang ◽

Chao Mei ◽

Peiyu Chuang ◽

Tingting Song ◽

Hailin Su ◽

...

Keyword(s):

Spin Coating ◽

Valence State ◽

Sol Gel ◽

Spin Coating Method ◽

Coating Method ◽

Mn Doped

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Synthesis and characterization of Mg–Zn ferrite based flexible microwave composites and its application as SNG metamaterial

Scientific Reports ◽

10.1038/s41598-021-87100-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Md Atiqur Rahman ◽

Mohammad Tariqul Islam ◽

Mandeep Singh Jit Singh ◽

Md Samsuzzaman ◽

Muhammad E. H. Chowdhury

Keyword(s):

Low Cost ◽

Sol Gel ◽

Microwave Frequency ◽

Dielectric Substrate ◽

Dielectric Constants ◽

Potential Candidate ◽

Flexible Composites ◽

Average Grain Size ◽

Zn Ferrite ◽

High Flexibility

AbstractIn this article, we propose SNG (single negative) metamaterial fabricated on Mg–Zn ferrite-based flexible microwave composites. Firstly, the flexible composites are synthesized by the sol-gel method having four different molecular compositions of MgxZn(1−x)Fe2O4, which are denoted as Mg20, Mg40, Mg60, and Mg80. The structural, morphological, and microwave properties of the synthesized flexible composites are analyzed using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and conventional dielectric assessment kit (DAK) to justify their possible application as dielectric substrate at microwave frequency regime. Thus the average grain size is found from 20 to 24 nm, and the dielectric constants are 6.01, 5.10, 4.19, and 3.28, as well as loss tangents, are 0.002, 0.004, 0.006, and 0.008 for the prepared Mg–Zn ferrites, i.e., Mg20, Mg40, Mg60, and Mg80 respectively. Besides, the prepared low-cost Mg–Zn ferrite composites exhibit high flexibility and lightweight, which makes them a potential candidate as a metamaterial substrate. Furthermore, a single negative (SNG) metamaterial unit cell is fabricated on the prepared, flexible microwave composites, and their essential electromagnetic behaviors are observed. Very good effective medium ratios (EMR) vales are obtained from 14.65 to 18.47, which ensure the compactness of the fabricated prototypes with a physical dimension of 8 × 6.5 mm2. Also, the proposed materials have shown better performances comparing with conventional FR4 and RO4533 materials, and they have covered S-, C-, X-, Ku-, and K-band of microwave frequency region. Thus, the prepared, flexible SNG metamaterials on MgxZn(1−x)Fe2O4 composites are suitable for microwave and flexible technologies.

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