SYNTHESIS AND OPTICAL CHARACTERIZATION OF PYROELECTRIC NANOPOWDERS BASED ON PZT (95/5)

Pb(Zr1-x, Tix)O3 (x = 0.05) with pyroelectric properties have been synthesized by sol–gel technique at low temperatures. XRD results indicate that the powder has perovskite structure without secondary phases and the average of particle size was estimated to be about 40 nm in diameters. The optical constants such as refractive index, n, extinction coefficient, k, and the dielectric function of PZT nanopowders have been investigated by Fourier transmittance infrared (FTIR) spectrum and Kramers–Kronig (KK) analysis program. The use of the KK method to analyze the normal incidence infrared (IR) reflectance spectra with a single resonance has also been described. The results indicated that the optical constant increases slowly as temperature of calcinations increases.

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SYNTHESIS AND STRUCTURE OF PURE AND Mn-DOPED ZINC OXIDE NANOPOWDERS

International Journal of Nanoscience ◽

10.1142/s0219581x1000648x ◽

2010 ◽

Vol 09 (01n02) ◽

pp. 19-28 ◽

Cited By ~ 14

Author(s):

M. EBRAHIMIZADEH ABRISHAMI ◽

S. M. HOSSEINI ◽

E. ATTARAN KAKHKI ◽

A. KOMPANY ◽

M. GHASEMIFARD

Keyword(s):

Optical Constants ◽

Magnetic Impurity ◽

Sol Gel ◽

Optical Characterization ◽

Secondary Phases ◽

X Ray Diffraction ◽

X Ray ◽

Gel Technique ◽

Size And Morphology ◽

Mn Doped

Zn 1-x Mn x O (x = 0, 0.02, 0.06, 0.10, 0.15) nanopowders were synthesized by the sol–gel technique calcinated at low temperatures. By decreasing the grain size in ZnO , the solubility of magnetic impurity has been increased and no detectable secondary phases were observed even in the high Mn -doping samples. The phase formation, size and morphology of nanoparticles were investigated using X-ray diffraction and SEM observations. The samples were ferromagnetic and the Curie point was found in the range 150–170 K for Zn0.94Mn0.06O and 135–150 K for Zn0.98Mn0.02O . Optical characterization and the effect of doping were carried out by means of Fourier transform infrared (FTIR) spectroscopy. Kramers–Kronig analysis was employed to evaluate the optical constants of pure ZnO and ZnO:Mn nanopowders.

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CHARACTERIZATION OF ZINC OXIDE NANOPOWDERS DOPED WITH MnO

Modern Physics Letters B ◽

10.1142/s0217984910022822 ◽

2010 ◽

Vol 24 (08) ◽

pp. 749-760 ◽

Cited By ~ 1

Author(s):

M. EBRAHIMIZADEH ABRISHAMI ◽

E. ATTARAN KAKHKI ◽

S. M. HOSSEINI ◽

A. KOMPANY

Keyword(s):

Optical Constants ◽

Optical Band Gap ◽

Sol Gel ◽

Secondary Phase ◽

Band Gap Energy ◽

Gel Technique ◽

Size And Morphology ◽

Mn Doped ◽

Compositional Characterization

Pure ZnO and Zn 1-x Mn x O (x=0.02 and 0.06) nanopowders have been synthesized by sol–gel technique at low temperatures. XRD results indicated that the crystal structure is hexagonal and there is no secondary phase. The compositional characterization of Mn -doped samples was investigated by EDX spectra. The size and morphology of nanoparticles were obtained by SEM and TEM images. Optical constants such as refractive index and extinction coefficient were evaluated from transmittance spectrum in UV region. The optical band gap energy showed a red-shift from 3.22 eV to 3.14 eV for pure and Zn 0.94 Mn 0.06 O , respectively. The Curie temperature of Mn -doped ZnO samples were determined and at room temperature no ferromagnetism state was observed.

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