preparation of perovskites nanoparticles by doping of rare earth metals

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2. 2
Department of Chemistry
The Islamia University of
Bahawalpur

3. 3
TiTle
of
presenTaTio
n
The effect of Bi and Zr on structural, electrical and
dielectric behavior of nanostructured GdFeO3 perovskites
fabricated via micro-emulsion route.

4. ConTenTs
4

5. nano
 The word ‘ nano ’ is derived from latin, means dwarf.
 A nanometre is a unit of length in the metric system,
equal to one billionth of a meter ( i.e, nm = 10 -9
m).
5
Nano-batteries are 200 nm
in diameter.
2 billion could fit on the
surface of a nickel.

6. WHaT is nanoTeCHnoloGY?
6
Structures
(e.g. materials)
Devices
(e.g. sensors)
Systems
(e.g. NEMS)
Nanotechnology is the
manipulation of matter
at the nanometer scale
to create novel
structures, devices and
systems.

7. nanoparTiCles
 Definition: “ Nanoparticles are sub-nano-sized
colloidal structures composed of synthetic or semi-
synthetic polymers.”
 Amorphous or crystalline forms.
 Size range (1 – 100 nm).
 Size of nanoparticles < wavelength of light.
 Nanoparticles have adverse health effects.
7

8. ClassifiCaTion of nanoMaTerials
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 1 dimension <
100nm
 2 dimensions <
100nm
 Zero or 3
dimensions <
100nm
 nanorods,
nanowires etc.
 Tubes, fibers,
platelets, etc.
 Particles, quantum
dots, hollow
Spheres, etc.
Classification Examples

9. MaTerial seleCTion faCTors
 Material selection for preparation of
nanoparticles depend on following factors
a) Size of nanoparticles required
b) Aqueous solubility and stability
c) Surface characteristics as charge
and permeability
d) Degree of toxicity
e) Structure etc
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Applications
Chemical
Catalysis
MedicalPaints
Nano
Coating
Device
fabrication
s
Cardiac tissue grown with the
help of nanofiber filamentsClear coating gold nanoparticles

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AIMS OF THIS WORK
 To prepare the GdFeO3 perovskites in the nano-regime
size i.e. 1-100 nm.
 To perform successful doping of rare earth metal Bi3+
& Zr+4
in GdFeO3.
 To lower down the dielectric parameters values by
doping of rare earth Bi3+
and Zr+4
ions.
 To increase the resistivity by doping of rare earth Bi3+
and Zr+4
ions.
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12. EXPERIMENTAL WORK
 Samples synthesized by micro-emulsion method.
 Samples prepared by Gadolinium (III) Chloride hexahydrate
(GdCl3.6H2O), Iron (III) Nitrate non-hydrate (Fe(NO3)3.9H2O,
Bismith Nitrate (Bi(NO3)3.5H2O, Zirconyl chloride octahydrate
(Cl2OZr.8H2O), Cetyltrimethylammonium bromide
(C16H33)N(CH3)3Br), Aqueous ammonia (NH4OH), solutions.
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13. RESULTS AND
DISCUSSION
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14. CONTENTS
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 Thermogarvimetric
analysis (TGA)
 X-Ray Diffraction
Analysis (XRD)
 Scanning electron
microscope (SEM)
 Fourier transform
infrared spectroscopy
(FTIR)
 Magnetic measurements
 DC Electrical properties
 Dielectric parameters

15. THERMOGARVIMETRIC ANALYSIS
(TGA)
 TGA analysis carried out to observed the posible changes in phase
development.
 The weight loss changes are determined by TGA analysis.
 The annealing temperature that was estimated from TGA graph.
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16. Miller indices
(hkl)
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X-RAY DIFFRACTION ANALYSIS (XRD)
All peaks of Gd1-xBixFe1-yZryO3 are matched with standard
patterns of GdFeO3 (ICSD-01-072-1155).

17. X-RAY DIFFRACTION ANALYSIS (XRD)
 XRD was used to find structural parameters
(crystallite size, lattice constant, cell volume).
 Peaks confirm crystalline structure.
 Miller indices confirm single phase and orthorhombic
structure
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18. CRYSTALLITE SIZE
 Calculated using Scherer's formula.
 Increase from 24.77 to 52.61nm because Ionic radii
of Bi & Zr are higher than Gd & Fe.
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θβ
λ
Cos
K
D
×
=

19. Paramete
rs
x = 0 x= 0.15 x = 0.30 x = 0.45 x = 0 .60
y = 0 y = 0.15 y = 0.30 y= 0.45 y = 0.60
Lattice
constant
a/Å
5.3477 5.3294 5.4816 5.3672 5.3466
Lattice
constant
b/Å
5.6566 5.6481 5.5929 5.5898 5.6239
Lattice
constant
c/Å
7.5062 7.4619 7.6466 7.6848 7.6478
Cell
Volume/Å
3
227.06 224.61 234.44 230.56 229.96
Crystallit
e Size/nm
24.77 42.11 42.08 30.05 52.61 19
Cell parameters (a, b and c), cell volume and crystallite size
for “Gd1-xBixFe1-yZryo3” nanoparticles

20. SCANNING ELECTRON MICROSCOPE (SEM)
 Shows surface morphology and grain size of particle.
 SEM estimated size of particles also found compatible
with that of the found by XRD data.
 Estimated the average particles size is ~50nm.
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Figure : Typical SEM image of
Gd0.44Bi0.60Fe0.44Zr0.60O3
perovskite nanoparticles.

21. FOURIER TRANSFORM INFRARED SPECTROSCOPY
(FTIR)
 Measurements made in 400–4000 cm-1
frequency range.
 Two strong absorptive bands at about 414.5 and 427.5
were attributed to Fe-O and O-Fe-O (bending)
respectively.
 The IR band at 402 cm-1
is due to Gd-O (steching).
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(Gd-O)
(o-Fe-O)
(Fe-O)

22. MAGNETIC MEASUREMENTS
 Magnetic measurements carried out at room
temperature (VSM lakeshore-74071).
 The magnetization of all the compositions of
nanoparticles recorded against applied magnetic field
in the range of -10,000 to 10,000 G.
 The hysteresis loop of all x and y values exhibited same
behavior that is diamagnetic and paramagnetic.
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23.  Magnetic parameter (coercivity , Magnetization and
retentivity) observed very low from hysteresis loop.
 The magnetic measurements has been inferred that
these materials are not suitable for magnetic data
storage devices applications.
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24. DC ELECTRICAL PROPERTIES
 Electrical resistivity of perovskite nanoparticles was
carried out at variable temperature.
 Two point probe method used.
 Electric resistivity of nanoparticles approximately
becomes constant at high temperature range.
 This behavior suggested that these materials can be
use for fabrication of switching materials.
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At high temperature es exchange Fe+3
to Fe+2
high
And as a result resistivity decrease (becomes constant).
-

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Three-fold increase in resistivity of Gd0.40Bi0.60Fe0.40Zr0.60O3 is
observed which is due to increase in dopant ratio.
Maximum resistivity

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 The variation of dielectric parameters as a function
of frequency from 6 kHz to 5 MHz range.
 At low frequency, high values of dielectric
parameters.
 Dielectric parameters become approximately
constant at higher frequencies.
 The low dielectric loss increase the efficiency and
lower the noise.
 Dielectric properties decrease with increasing
dopant contents.
DIELECTRIC PARAMETERS

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A decrease in the dielectric tangent loss peak with increasing Bi+3
– Zr+4
concentration suggested that the hopping or jump probability between Fe3+
and Fe2+
is reduced.

30. Parameters Frequency x=0 x=0.15 x=0.30 x=0.45 x=0.60
y=0 y=0.15 y=0.30 y=0.45 y=0.60
Dielectric
Constant
0.03 MHz 72.35187 86.54801 35.92825 43.17773 25.21658
2.3 MHz 19.86759 23.82585 26.02859 31.21633 23.15248
4.0 MHz 18.81732 22.58802 25.75161 30.92459 23.06849
5.0 MHz 18.46723 22.14317 25.61189 30.63285 23.0539
Dielectric Loss
0.03 MHz 57.3804 82.36679 10.18469 14.68766 1.76406
2.3 MHz 2.99929 4.31622 1.22997 1.77013 0.34428
4.0 MHz 2.28979 3.29835 0.99047 1.42733 0.30216
5.0 MHz 2.05545 2.95751 0.88704 1.27312 0.25851
Tangent
Loss
0.03 MHz 0.79307 0.95169 0.28347 0.34017 0.06996
2.3 MHz 0.15096 0.18116 0.04725 0.05671 0.01487
4.0 MHz 0.12169 0.14602 0.03846 0.04616 0.0131
5.0 MHz 0.1113 0.13356 0.03463 0.04156 0.01121
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Various dielectric parameters for “Gd1-xBixFe1-yZryO3”
nanoparticles at some selected frequencies

31. CONCLUSION
 The particles of “Gd1-xBixFe1-yZrO3” in the nano-scale range
were successfully synthesized involving simultaneous
double ions substitution philosophy.
 Various experimental techniques like TGA, XRD, FTIR,
SEM and VSM were used to characterize the
nanoparticles. All these techniques results were found
compatible with each other.
 These materials exhibited semiconductor to metal
transition behavior. 31

32.  The resistivity increases as a result dielectric
parameters decreased.
 Potential application of “Gd1-xBixFe1-yZrO3” nanoparticles
in telecommunication devices and fabrication of
switching devices.
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33. PUBLICATION
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This work has been published in ceramics international
journal

34. ACKNOWLEDGEMENT
 The chairman Prof. Dr. Faiz-ul-Hassan Nasim Islamia
University of Bahawalpur
 Dr. Muhammad Farooq Warsi (supervisor)
 Dr. M. Shahid (KAUST-KSA for SEM analysis)
 Zaheer Gilani (Ph.D Scholar), Khawaja Imtiaz (Ph.D
Scholar), Rajjab Ali (Ph.D Scholar)
 QAU for XRD, FTIR and electrical measurements.
 NUST dielectric measurements.
 PU for magnetic measurements.
 All lab fellows, technical and lab staff of the department34

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