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Abedul-Samad Jawabreh An najah National Univresity Directed by Dr.Issam Rasheed. Production of Nanoparticles by laser. overview.
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Abedul-SamadJawabreh An najah National Univresity Directed by Dr.IssamRasheed Production of Nanoparticles by laser
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 Introduction
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 C60 History of Nanotechnology
1986 – “Engines of Creation” - First book on nanotechnology by K. Eric Drexler. • 1999 – “Nanomedicine” – 1stnanomedicine book • by R. Freitas • 2000 – “National Nanotechnology Initiative” gold nano particles
Nanoscale materials 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
Nanoscale ww.mathworks.com Fullerenes C60 22 cm 0.7 nm 12,756 Km 1.27 × 107 m 0.7 × 10-9 m 0.22 m 1 billion times smaller 10 millions times smaller
100 nanometers 1 nanometer (nm) الأبعاد في المقياس رأس دبوس 1-2 mm 1 cm 10 mm Virus: 10-100 nm. Hemoglobin: 7 nm. Water (H2O): 0.2 nm 10-2 m 0.1 cm 1 mm 10-3 m شعرة بشرية ~ 60-100 m 0.1 mm 100 μm 10-4 m 0.01 mm 10 μm 10-5 m كريات دم حمراء مع كرية بيضاء ~2-5 m 1 μm 1000 nm 10-6 m Visible spectrum 0.1 μm 100 nm 10-7 m DNA ~2.5 nm width 0.01 mm 10 nm 10-8 m 10-9 m ذرات ومسافات سيليكون ~tenths of nm 1 nm 10-10 m 0.1 nm
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. Nanomaterialproperetys
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. Laser Ablation and Thin-Film Deposition (PLD)
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 . The basic idea of the technique
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, Laser-Target Interaction
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
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 PLD The process of PLD can generally be divided into four stages:
There is an increasing interest in the production andcharacterization ofnanoparticles of different elementsand compounds due to their importance in fundamentalresearch as well as in technological applications [Different techniques for the production ofnanoparticles have been developed, such as electrochemical deposition, ballmilling, sputtering and laser ablation. In the method ofproduction of nanoparticlesby laser ablation,nanoparticles are produced around the ablated area oron a suitably chosen substrate either as isolated entitiesor as a continuous deposit (agglomeration ofnanoparticles), by pulsed laser deposition ablation of asolid target in ambient air, vacuum or in a controlledatmosphere of some gas. Alternatively, acolloidal solution of nanoparticles is produced byablating the target while it is immersed in a liquidsolution which may also contain a suitable surfactantto prevent agglomeration of the nanoparticles and increase the stability of the solution NANO-PARTICLE GENERATION BY FEMTO SECOND LASER ABLATION
Femtosecond laser ablation as a method for theproduction of nanoparticles offers mainlymany 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 .
let’s see the video… How to produce nano particles by laser
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 Applications of Nanotechnology
[1] Wikipedia, There's Plenty of Room at the Bottom, <http://en.wikipedia.org/wiki/Plenty_of_Room_at_the_Bottom> [2]Richard Feynman, There's Plenty of Room at the Bottom, Zyvex, <http://www.zyvex.com/nanotech/feynman.html> [3]Chris Toumey, Apostolic Succession, <http://pr.caltech.edu/periodicals/EandS/articles/LXVIII1_2/Feynman.pdf> [4]. Hirai, H ,Toshima, N. Tailored Metal Catalysts; Iwasawa, Y., Ed.; D. Reidel: Dordrecht, pp 87-140, (1986). References
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