ALUMINA NANO PARTICLES
A presentation by:
SAMAR NOURELDIN
OMER MOHAMMED
MARAM FARAH
Alumina can called :
aloxide
aloxite,
 alundum
depending on particular forms or
applications.
Alumina nanoparticles applications
 alumina are Thermal insulator, High Temperature
Stability will allow it to use in man...
Sol-Jel method.
emulsion combustion method (ECM).
Spray Pyrolysis method(hot wall aerosol
synthesis method ).
Hydrothe...
Here we will explain only the three
most important methods
• nanoscale alpha-alumina (α-Al2O3) powder is
smaller than (Nano-Al2O3) but it’s difficult to obtain
due to :
α-Al2O3 is ...
Sol-Jel
method
 uses relatively low temperature.
 can create very fine powder.
the possibility to obtain high purity materials.
Sol-ge...
• There are different precursors used in the
synthesis of alumina by sol-gel method were of
different chemical nature such...
Particle synthesis
Particle characterization
The produced particles
characterized by, X-ray diffraction
The produced particles
characterized by SEM micrographs
the particle become finer
and less agglomerated until
48 hour stirring. The particle
started to agglomerate and
to be more...
TEM analysis
figure” a”
The size of particle
after 24 hours of
stirring in range of
270–320 nm and
had a lot of
agglomeration.
Figure” b”
the size of particles,
after 36 hours of
stirring, fell in the
range of 250–
300 nm, and had a
lot of agglomera...
Figure”c”
the size of particles,
after 48 hours of
stirring, fell in the
range of 20-30 nm,
and had a good
quality of disp...
Figure (d)
after 60 hours of
stirring, the sizes of
particles were in
the range of 150–
200 nm and a lot of
agglomeration ...
Spray
Pyrolysis
method
Its main application
In metal-matrix composites for
nanoreinforcements
Method description
• it’s based on ultrasonic generation of
micrometric-sized aerosol droplets and their
decomposition at ...
Particle synthesis
 An aqueous precursor solution prepared by dissolving the corresponding
amount of aluminium nitrate no...
 The amorphous and polycrystalline character of the particles.
 Initially the particle morphology does not change signif...
Experimental X-ray diffraction patterns
SEM
micrograph of
“as-prepared”
Al2O3
particles,
TEM
analysis(secondary
particles)
(ECM)
method
this method was originally developed in
1997 in Japan.
It is compination of :
emulsion process + combustion
technology
...
produce high performance ceramic
powders
Its main application
An isolated small reaction field.
Short reaction period ” less than half a second”.
gives synthesize fine and chemicall...
Particle formation
mechanism(synthesis)
it is simmillary like the Hollow particles have been
synthesized by spray pyrolys...
collection of the ceramic powder produced
combustion of the atomized emulsion
preparation of an emulsion “ An aqueous solu...
Particle characterization
 The particles are spherical in shape.
 their diameters in the range 200–800 nm.
 The particl...
TEM image of the
typical alumina
powder
synthesized by
the
ECM(1mikro.m)
XRD profile of alumina
powder
03/05/2014 copyright 2006 www.brainybetty.com ALL RIGHTS RESERVED. 40
Nanotechnology Alumina Nano particles
Nanotechnology Alumina Nano particles
Nanotechnology Alumina Nano particles
of 40

Nanotechnology Alumina Nano particles

Alumina Nano particles
Published on: Mar 3, 2016
Published in: Engineering      Technology      Business      
Source: www.slideshare.net


Transcripts - Nanotechnology Alumina Nano particles

  • 1. ALUMINA NANO PARTICLES A presentation by: SAMAR NOURELDIN OMER MOHAMMED MARAM FARAH
  • 2. Alumina can called : aloxide aloxite,  alundum depending on particular forms or applications.
  • 3. Alumina nanoparticles applications  alumina are Thermal insulator, High Temperature Stability will allow it to use in many industrial and institutional work.  in ceramic industry.  In polishing/abrasive applications.  as an absorbent.  in the refractories  as catalysts.  wear resistant coating.  medium for chemical chromatography
  • 4. Sol-Jel method. emulsion combustion method (ECM). Spray Pyrolysis method(hot wall aerosol synthesis method ). Hydrothermal method. Co-Precipitation method. Mechanical milling. Vapour phase reaction and Combustion method. Methods of preparation
  • 5. Here we will explain only the three most important methods
  • 6. • nanoscale alpha-alumina (α-Al2O3) powder is smaller than (Nano-Al2O3) but it’s difficult to obtain due to : α-Al2O3 is in a stable phase after calcining at high temperature. α-Al2O3 particles tend to aggregate during dehydration process in wet chemistry method. Sol-gel method can solve these problems
  • 7. Sol-Jel method
  • 8.  uses relatively low temperature.  can create very fine powder. the possibility to obtain high purity materials. Sol-gel method advantages
  • 9. • There are different precursors used in the synthesis of alumina by sol-gel method were of different chemical nature such as: inorganic – aluminium chloride (AlCl3) . organic– aluminium triisopropylate (C3H7O)3Al. Aluminum isopropoxide Al (OC3H7)3
  • 10. Particle synthesis
  • 11. Particle characterization
  • 12. The produced particles characterized by, X-ray diffraction
  • 13. The produced particles characterized by SEM micrographs
  • 14. the particle become finer and less agglomerated until 48 hour stirring. The particle started to agglomerate and to be more dense in structure at 60 h.
  • 15. TEM analysis
  • 16. figure” a” The size of particle after 24 hours of stirring in range of 270–320 nm and had a lot of agglomeration.
  • 17. Figure” b” the size of particles, after 36 hours of stirring, fell in the range of 250– 300 nm, and had a lot of agglomeration.
  • 18. Figure”c” the size of particles, after 48 hours of stirring, fell in the range of 20-30 nm, and had a good quality of dispersion.
  • 19. Figure (d) after 60 hours of stirring, the sizes of particles were in the range of 150– 200 nm and a lot of agglomeration and only little dispersion were observed
  • 20. Spray Pyrolysis method
  • 21. Its main application In metal-matrix composites for nanoreinforcements
  • 22. Method description • it’s based on ultrasonic generation of micrometric-sized aerosol droplets and their decomposition at intermediate temperatures (400-800ºC). • it possible to control important particle properties (size, morphology, chemical composition, etc.) simply by controlling the process parameters (residence time, decomposition temperature).
  • 23. Particle synthesis  An aqueous precursor solution prepared by dissolving the corresponding amount of aluminium nitrate nonahydrate (Al(NO3)3·9H2O.  The initial solution was atomized using an ultrasonic vibrating frequency of 2.1·106 s-1.  The aerosol transported into a reaction zone and decomposed at 700°C.  Air used as a carrier gas .  the powders were isothermally annealed in air at 800 - 1300 oC for 12 hours (chamber furnace CHESA) to promote phase crystallization.  The particles water collected at exhaust “.  The predicted particle size, Dp, can be expressed as a function of the droplet size, Do.
  • 24.  The amorphous and polycrystalline character of the particles.  Initially the particle morphology does not change significantly with annealing.  As the temperature of thermal treating increase , the η-Al2O3 phase continues and the particles tends to form the peaks (alfa-Al2O3 phase) and loss there spherical shape .  there is a contamination of SiO2 from the quartz tube.  particles obtained by aerosol decomposition are spherical, smooth, non-aggregated and relatively uniform in size(≤ 400 nm).  confirm high compositional uniformity and the exclusive presence of the constitutive elements (Al and O). Particle characterization
  • 25. Experimental X-ray diffraction patterns
  • 26. SEM micrograph of “as-prepared” Al2O3 particles,
  • 27. TEM analysis(secondary particles)
  • 28. (ECM) method
  • 29. this method was originally developed in 1997 in Japan. It is compination of : emulsion process + combustion technology The ECM is classified into liquid phase syntheses but it also has the features of gas phase syntheses.
  • 30. produce high performance ceramic powders Its main application
  • 31. An isolated small reaction field. Short reaction period ” less than half a second”. gives synthesize fine and chemically homogeneous metal oxide powders. It’s a continuous fabrication procedure which contributes to lower production costs. (ECM)method advantages
  • 32. Particle formation mechanism(synthesis) it is simmillary like the Hollow particles have been synthesized by spray pyrolysis where the aqueous droplets containing metal ions are rapidly heated at their surface. but here the surface of emulsion droplets is rapidly heated by the combustion of the surrounding kerosene film.  The fast heating rate results in the unusually thin shell structure .
  • 33. collection of the ceramic powder produced combustion of the atomized emulsion preparation of an emulsion “ An aqueous solution W/O type Preparation procedures
  • 34. Particle characterization  The particles are spherical in shape.  their diameters in the range 200–800 nm.  The particles exhibited the unique characteristics of hollow structure with extremely thin (10 nm) shell.  The specific surface area is 56m2/g.  In XRD profile of the hollow alumina powder The broad peaks are identified with gamma phase alumina.
  • 35. TEM image of the typical alumina powder synthesized by the ECM(1mikro.m)
  • 36. XRD profile of alumina powder
  • 37. 03/05/2014 copyright 2006 www.brainybetty.com ALL RIGHTS RESERVED. 40

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