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Abedul-Samad Jawabreh An najah National Univresity Directed by Dr.Issam Rasheed.

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Presentation on theme: "Abedul-Samad Jawabreh An najah National Univresity Directed by Dr.Issam Rasheed."— Presentation transcript:

1 Abedul-Samad Jawabreh An najah National Univresity Directed by Dr.Issam Rasheed

2 History of Nanotechnology Nanoscale materials Properties of nanomaterials Laser Ablation and Thin-Film Deposition (PLD) Laser Ablation in liquids Applications of Nanotechnology

3 Nanotechnology is beginning to allow scientists, engineers, and physicians to work at the cellular and molecular levels to produce major advances in the life of sciences and healthcare. Nanostructures and nanoparticles differ in their chemical,Optical, magnetic and electric properties from the bulk material of which they are made, and hence enable new application possibilities. the excellent properties of these materials when compared with their bulk counterparts provide a very promising future for their use in many fields The challenge does not focus on the synthesis of nanoparticles but rather on the integration of these nanoparticles into material

4  The first one who discribe the nano scale is Richard Feynman (he has the Nobel )  In 1959 Feynman give a licture about “ There's Plenty of Room at theBottom” “The nanoteqneqe in our life” 1974 – “Nanotechnology” - tanjushee uses the term nanotechnology for the first time to describe the science and technology of processing or building parts with nanometric tolerances.  1982 – scanning tunneling microscope Was invented by the two science Gerd Binnig & Heinrich Rohrer  1985 – “Buckyball” - Scientists at Rice University discover C 60

5 1986 – “Engines of Creation” - First book on nanotechnology by K. Eric Drexler. 1999 – “Nanomedicine” – 1 st nanomedicine book by R. Freitas 2000 – “National Nanotechnology Initiative” gold nano particles

6  Nano = 10 -9 m  Materials with dimensions and range of 100 nm to 0.1 nm  You can put 10^7 H atom side by side in 1 mm  One nanometer spans 3-5 atoms lined up in a row  Human hair is five orders of magnitude larger than nanomaterials

7 1.27 × 10 7 m ww.mathworks.com 0.22 m 0.7 × 10 -9 m Fullerenes C 60 12,756 Km 22 cm 0.7 nm 10 millions times smaller 1 billion times smaller

8 الأبعاد في المقياس 0.1 nm 0.01 mm 10 nm 0.1 μm 100 nm 0.01 mm 10 μm 0.1 mm 100 μm 1 cm 10 mm 10 -2 m 10 -3 m 10 -4 m 10 -5 m 10 -6 m 10 -7 m 10 -8 m 10 -9 m 10 -10 m Visible spectrum 1 nm 1 μm 1000 nm 0.1 cm 1 mm ذرات ومسافات سيليكون ~tenths of nm رأس دبوس 1-2 mm كريات دم حمراء مع كرية بيضاء ~2-5  m DNA ~2.5 nm width شعرة بشرية ~ 60-100  m 1 nanometer (nm) 100 nanometers Virus: 10-100 nm. Hemoglobin: 7 nm. Water (H 2 O): 0.2 nm

9  Color : The colour of a material is determined by the wavelength of light photons absorbed by it. So, the clusters of different sizes will have different energy level separations hence different colours and the size of the cluster can be used to estimate the colour of the material.  Geometric Structure : The geometric structure of large nanoparticles depends on size.  Basic structure : the nanoparticles Metal exist as a group of metal atoms forming a cluster.

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11 The application of laser ablation is called pulsed laser deposition (PLD). laser ablation was mainly used for the analysis of various materials and further development of PLD was slow. After the discovery of high-temperature superconductivity in 1986, the research interest in PLD increased dramatically. The first successful deposition of a YBCO film was made in 1987. The principle of laser ablation is illustrated in Fig. 1.

12  exploit high-power laser pulses, e.g., from an excimer or a Nd:YAG laser.  The focused laser pulses are absorbed in the target surface in a small volume.  high-pressure gas is produced in the surface layer. As a result of the pressure gradient, particles is ejected normal to the target surface.  The particle cloud absorbs a large amount of energy from the laser beam producing an expansion of hot plasma (plume) through the deposition chamber  The ablated species condense on the substrate placed opposite to the target forming a thin film.

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14 The interaction between laser pulses and the target depends strongly on the intensity of the incoming laser beam. There are many different mechanisms through which energy can be transferred to the target and the most important ones is collisional sputtering,

15  The mechanism is of great importance if the incoming beam consists of massive particles, such as ions. In the case of photons, the maximum transfer of energy (E2) is negligible as one can see from the following equation :- E1: the energy of the incoming particles M1: the mass of the incoming particles M2: the mass of the target particles

16  Laser ablation of the target material and creation of plasma  Dynamic of the plasma  Deposition of the ablation material on the substrate  Nucleation and growth of the film on the substrate Surface The process of PLD can generally be divided into four stages:

17 There is an increasing interest in the production and characterization of nanoparticles of different elements and compounds due to their importance in fundamental research as well as in technological applications [Different techniques for the production of nanoparticles have been developed, such as electrochemical deposition, ball milling, sputtering and laser ablation. In the method of production of nanoparticles by laser ablation, nanoparticles are produced around the ablated area or on a suitably chosen substrate either as isolated entities or as a continuous deposit (agglomeration of nanoparticles), by pulsed laser deposition ablation of asolid target in ambient air, vacuum or in a controlled atmosphere of some gas. Alternatively, acolloidal solution of nanoparticles is produced by ablating the target while it is immersed in a liquid solution which may also contain a suitable surfactant to prevent agglomeration of the nanoparticles and increase the stability of the solution

18 Femtosecond laser ablation as a method for the production of nanoparticles offers mainly many advantages : -  the ejected particles do not interact with the laser beam 2. the mechanism of formation of nanoparticles is different as compared to the case of ablation with long pulses.

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20 let’s see the video…

21 There is too many application of nanotechnology includes 1- cosmatics 2- medicin and drugs 3- bio enginearing 4- optical enginearing 5- nano devices 6- energy

22  [1] Wikipedia, There's Plenty of Room at the Bottom,  [2]Richard Feynman, There's Plenty of Room at the Bottom, Zyvex,  [3]Chris Toumey, Apostolic Succession,  [4]. Hirai, H,Toshima, N. Tailored Metal Catalysts; Iwasawa, Y., Ed.; D. Reidel: Dordrecht, pp 87-140, (1986).

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