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Your search keyword '"Sharma, P."' showing total 4 results
Start Over Author "Sharma, P." Topic doping agents (chemistry) Topic x-ray diffraction
4 results on '"Sharma, P."'

1. Investigation of Magnetic and Optical Properties of Mn-Doped SnO2 at Different Annealing Temperatures.

Author

Sunaina, A. Sharma and Sharma, P.

Subjects
*MAGNETIC properties, *OPTICAL properties, *BAND gaps, *ULTRAVIOLET-visible spectroscopy, *TEMPERATURE, *MAGNETOOPTICS, *TIN oxides, *MANGANESE, *DOPING agents (Chemistry), *COPRECIPITATION (Chemistry), *X-ray diffraction, *SINTERING, *ANNEALING of crystals
Abstract

In this paper, a systematic investigation has been done to study the effect of variation in annealing temperature on magnetic and optical properties of Mn-doped SnO2. Coprecipitation technique has been used to synthesize Sn1-xMnxO2 samples with low Mn concentration (2%). Pristine SnO2 is sintered at 350 °C. Mn-doped SnO2 samples are sintered at 350, 450, 550 and 650 °C. The structures of tetragonal rutile of SnO2 and Mndoped SnO2 have been confirmed by the XRD pattern. Typical ferromagnetic ordering has been observed for Mn-doped SnO2 samples annealed at different temperatures. However, on increasing the annealing temperature saturation magnetization as well as the coercive field decreases, indicating a crucial phase transformation from ferromagnetism to paramagnetism. UV-Vis spectroscopy shows increase in absorbance and a slight shift in the absorption edge with Mn-doping at increasing annealing temperature indicating shifting of absorption peak towards higher wavelength. Tauc's plot has been used to find the optical band gap (Eg). [ABSTRACT FROM AUTHOR]

Published
2020
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2. Synthesis and Structural Study of Cr-Doped BaTiO3 by Xray Diffraction Technique and Williamson-Hall and Size Strain Plot Methods.

Author

Shrivastava, Anshu, Bisen, Supriya, Khan, Mehjabeen, Sharma, P., and Mishra, A.

Subjects
X-ray diffraction, DATA analysis, COMBUSTION, MICROWAVE sintering, TITANIUM dioxide, DOPING agents (Chemistry)
Abstract

X-ray diffraction technique has been employed in the current research work to determine the structure and composition of Cr-doped BaTiO3, because it is a very useful tool to study non-destructively the crystallographic structure, chemical composition and physical properties of BaTiO3. The XRD characterization has been conducted at IUC, UGCDAE CSR. The synthesis of the nano-material has been done using the Sol-Gel Auto Combustion technique. BaTiO3 is a versatile compound, predominantly known for its storage capacity. Thus, serving in innumerable devices such as MLCCs, PTCR and microwave dielectric ceramics. Analysis of the obtained data from the characterization techniques has been done using Origin software. The powder XRD confirms the crystalline compound of Cr-Doped BaTiO3 by comparing 2θ and intensity values with JCPDS values of the same compound. [ABSTRACT FROM AUTHOR]

Published
2019
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3. FTIR, powder XRD, TEM and dielectric studies of pure and zinc doped nano-hydroxyapatite.

Author

Tank, K. P., Sharma, P., Kanchan, D. K., and Joshi, M. J.

Subjects
*FOURIER transform infrared spectroscopy, *X-ray diffraction, *DOPING agents (Chemistry), *ZINC, *NANOPARTICLES, *HYDROXYAPATITE
Abstract

Hydroxyapatite, Ca10(PO4)6(OH)2 or HAP, is an important bio-material, which is having application in bone implants and dentistry. In the present study, zinc doped nano-hydroxyapatite (Zn-HAP) was synthesized via chemical precipitation route using surfactant mediated approach. The doping of zinc was confirmed by EDAX. The powder X-ray diffraction (XRD) pattern revealed the typical hydroxyapatite pattern with broadening and extra peaks were observed for higher concentration. The average crystallite size was calculated by applying the Scherrer's formula to powder XRD pattern and was found in the range of 16 to 33 nm. The morphology of synthesized nano-particles was also confirmed using TEM. FTIR spectroscopy was used to confirm the presence of various bonds. The dielectric study was carried out at room temperature within the frequency range from 102 Hz to 107 Hz and the variations of dielectric constant with frequency of applied field as well as with the concentration of zinc were studied. It was found that as the concentration of zinc increased the dielectric constant increased. The variations of dielectric loss and a.c. conductivity with frequency of applied field were studied. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Published
2011
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4. CaMoO4:Dy3+, K+ near White Light Emitting Phosphor: Structural, Optical and Dielectric Properties.

Author

Sharma, S.K., Dutta, S., Som, S., and Mandal, P.S.

Subjects
CALCIUM compounds, DYSPROSIUM, METAL ions, POTASSIUM isotopes, PHOSPHORS, OPTICAL properties of metals, DOPING agents (Chemistry), INORGANIC synthesis
Abstract

Undoped, Dy3+ doped and Dy3+, K+ codoped calcium molybdate phosphors have been synthesized by solid-state reaction method. X-ray diffraction studies reveal the tetragonal structure of the prepared phosphors having crystallite size 15–50 nm. Scanning electron microscopy (SEM) studies reveal the morphology and crystallite size of the prepared phosphors. Photoluminescence studies indicate that there are blue and yellow emissions at 489 and 576 nm, respectively corresponding to Dy3+ ion. The introduction of K+ ion significantly influences the blue and yellow emissions which causes the near white light emission from this codoped phosphor. The intense absorption peak of the codoped phosphor at 210 nm is attributed to the band gap and a shoulder at 240 nm appears due to charge transfer from oxygen ions to neighbouring molybdenum ions. The band gap of the codoped phosphor is calculated as 5.5 eV from the absorption studies. The dielectric properties such as permittivity and dielectric loss are studied as a function of frequency. [Copyright &y& Elsevier]

Published
2013
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