Hmmv jalandhar presented

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Hmmv jalandhar presented

  1. 1. DESIGNING NANOMATERIALS: NOVEL APPROACHES SHRIRAM INSTITUTE FOR INDUSTRIAL RESEARCH 19, UNIVERSITY ROAD, DELHI-110 007 Email : sridlhi@vsnl.com Website : www.shriraminstitute.org Presented by : Dr. R.K. KHANDAL
  2. 2. OUTLINE Scope Opportunities Challenges Nanomaterials SRI & Novel Nanomaterials  Classification  Size Effects  Shape Effects  Approaches  Novel Architecture
  3. 3. Nanomaterials: Materials consisting of particles of the size of nanometer Volume = Surface Area * Thickness  For a given volume:  Surface area Thickness  More atoms at surface than in the interior  Extraordinary activity SCOPE: DEFINITION
  4. 4. SCOPE : DOMAIN Keywords Domain Particle size Distribution in the continuous phase Modification of surfaces Interfacial tension Surfaces Interfaces Rising volume fraction Homogeneity of phases of dispersing phase  Domain of Nanotechnology: Multi-phase systems  Liquid : Liquid  Solid : Liquid  Surfaces and interfaces involving different phases  Gas : Liquid  Gas : Solid
  5. 5. Systems Process Emulsion Macro Micro Dispersion Coarse Fine Solution Colloid SCOPE: PROCESS A process to create a continuous dispersed phase as fine as possible for homogeneity with the dispersing phase (Liquid / Liquid; Gas/Liquid) (Solid / Liquid) (Solid / Liquid; Liquid/Liquid) Solubilization
  6. 6. SCOPE : DIMENSIONS What Happens Dimensions  Particle size More from less  Surface area Enhanced coverage  Activity Novel products  Efficiency Improved performance per unit mass  Maximum possible benefits from minimum possible inputs  Effecting changes through and at atomic scale
  7. 7. NANOSCIENCE TO NANOTECHNOLOGY“MACRO TO NANO” MATERIALS Copper Macro PROPERTIES Nano Opaque Transparent Platinum Catalyst Aluminium Stable Combustible Inert Gold Inert Catalyst  Unique properties at the nanoscale are the driving force for exploitation of nanomaterials
  8. 8. NANOSCIENCE TO NANOTECHNOLOGY NANOSCIENCE NANOTECHNOLOGYBiology Chemistry Physics Value Addition Performance Diversification  Measure of success of science and technology is to manufacture and commercialize!
  9. 9. OPPORTUNITIES: NANOTECHNOLOGY N A N O S C I E N C E Carbon Nanotube Nanowire N A N O T E C H N O L O G Y Carbon nanotube on plastics Array of Carbon nanotube-devices TiO2 Sunscreens Coatings Nano-TiO2
  10. 10. OPPORTUNITIES: NANOMATERIALS FOR INDUSTRIES NANOMATERIALS Electronics Chemicals Energy Transportation Medical/Biology Materials Water Purification Desalination Agriculture Fertilizers Packaging Coatings Light weight Efficiency Prosthesis Drug delivery Diagnosis Composites Coatings Construction Data storage High speed devices Catalysts Fuel Cells Batteries Nanotechnology has revolutionized various industries; only solution for the emerging needs
  11. 11. Process of making Nanomaterials Process steps Inputs Macro Micro Nano CHALLENGES: PROCESS TECHNOLOGY Challenge: To have a process that can convert macro materials into nano materials spontaneously & with minimum efforts Energy Bulk Sugar cube Nano Dissolved sugar/salt Bulk Output Salt
  12. 12. NANOMATERIALS:CLASSIFICATION Nanoparticles (Smoke, diesel, fumes) Nanocrystalline Materials Nanoparticle composites Nanocrystalline films Nanorods tubes (Carbon nano tubes) Inter connects Multi layer structure Nano Films Foils Nantube, reinforced composites Surface layers Class 1 Discrete Class 2 Surface Class 3 Bulk0-D d≤ 100 nm 1-D d≤ 100 nm 2-D d ≤ 100 nm Dimensionality Multi layer structure Nanowires & Nanotubes Multi layers 3-D 3-D nanomaterials are nanocomposites formed of two or more materials with very distinctive properties, act synergistically to create unique properties that cannot be achieved by single materials
  13. 13. NANOMATERIALS: SIZE DEPENDENCE Particle size (nm) Meltingpoint(K) Particle size (nm) SurfaceTension (mN/m) Particle size (µm)(nm) Strength Dielectric Constant Particle size (nm) 100 1000 Bulk Particle size affects the properties & thus overall behavior of the material Au Au Al PbTiO3
  14. 14. NANOMATERIALS : SHAPE DEPENDENT Sphere Cylinder Cube Dimension (nm) Surface/Volume(nm-1 ) Nanoscale materials have extremely high surface to volume ratios as compared to larger scale materials Sphere: S:V = 3 : r Cube : S:V = 6 : l Cylinder: S:V = 2 : r r = radius l = length
  15. 15. DESIGNING OF NANOMATERIALS: APPROACHES Assembled from nano building blocks From bulk  Control of size is dependent on end-use applications
  16. 16. DESIGNING OF NANOMATERIALS :SPHERES AND RODS Ag(I) or Au(III) salt + NaBH4 More Seeds + metal salt + ascorbic acid + CTAB Less Seeds + metal salt + ascorbic acid + CTAB Seed mediated growth is a good approach for the preparation of nanorods and nanowires of varying aspect ratios. Few seeds Longer rods Seeds (Stabilizing agent) (Stabilizing agent) [H]
  17. 17. Designing of Nanomaterials: Dendrimers Linear Branched Cross-linked Dendritic Flexible coil Rigid rod Cyclic (closed linear) Polyrotaxane Random short branches Random long branches Regular comb branches Regular star branches Lightly cross linked Densely cross linked Interpenetrating networks Hyper branched Ideal dendron Dendrimer X  New types of nanomaterials (nanocomposites) with unusual architecture are created by highly branched polymers.  Dendrimers have characteristic features of both macromolecules and the nanoparticles: Dendrimers help in controlling the particle size.
  18. 18. DESIGNING OF NANOMATERIALS: ENCAPSULATION TiO2 TiO2 - - - - - - TiO2 TiO2 - - - - - - MonomerPolymer Surfactant - -Radical Polymerization Latex Fe2O3-Particles Fe2O3-Particles Latex bead Pre-treatment Polymerization Copolymer layer Encapsulated particle Amphiphilic molecule Monomer Polymer encapsulated nanomaterials are used for targeted delivery of substances such as drugs. Dimensions of encapsulated substance is tens of nanometers and of the stabilizing shell is a few hundred micrometers.
  19. 19. Designing of Nanomaterials: Optical Incident Light Transmitted light (Spectral luminous gain, switching, fluorescence, etc. Optically functional particles Coating or fibers of the matrix formed  Metal ions can be introduced into polymeric fibers to produce colored light guides.  Polymer based nanocomposites containing well-dispersed inorganic particles can exhibit semiconducting properties, quantum dot effects, non-linear optical properties and extremely low or high refractive index.
  20. 20. DESIGNING OF NANOMATERIALS : MAGNETIC MATERIALS Isolated nanoparticles Nano particles Ultrafine Nanoparticles core shell morphology in the matrix Small magnetic nanoparticles embedded in a chemically dissimilar matrix Small particles dispersed in nanocrystalline matrix Magnetic property corer with polymer coating The characteristics of magnetic matrices depend on diversity of interconnected factors < 1 nm:Non-magnetic ~ 1-10 nm:Super paramagnetic >10 nm: Ferromagnetic Ex. Mn,Co,Fe &Ni 3M2O3.5Fe2O3 Ni0.5Zn0.4Cu0.1Fe2O3
  21. 21. DESIGNING OF NANOMATERIALS: ELECTRICAL MATERIALS Matrix  Conductivity of nanoparticles is higher than for micron size particles  Nanoparticles-polymer interactions influences electro-physical properties  Size & form of nanoparticles Magnetic characteristics  Conductivity can exist in every single metal nanoparticle Structures of composites Statistical Layered Chain Globular Examples: Ag,Ni,Cu,Zn
  22. 22. SRI’S EXPERIENCE SRI has developed nanomaterials for :  Optical applications  Effluent treatment
  23. 23. 23232323232323 LOW REFRACTIVE INDEX MATERIALS  The refractive index of low refractive index materials increases from 1.49 to 1.66. 1.41 1.47 1.53 1.59 1.65 1.71 0 10 20 30 40 50 60 70 80 90 100 % of additive Refractiveindex
  24. 24. 24242424 Refractive index increases with increase in percentage of metal salt. 1.41 1.42 1.43 1.44 1.45 1.46 1.47 1.48 0 5 10 15 20 25 30 Metal salt (% by wt) RefractiveIndex Barium Hydroxide Lead Monoxide Lanthanum Oxide EFFECT OF DISPERSION OF METAL SALTS ON THE REFRACTIVE INDEX OF ACRYLIC ACID
  25. 25. 252525252525 Effect of metal on refractive index  In-situ formation of nanoparticles of Ti The refractive index of the polymer increases from 1.45 to 1.53 1.44 1.46 1.48 1.5 1.52 1.54 0 2 4 6 % Ti RefractiveIndex
  26. 26. MATERIALS FOR ENERGY CONVERSION: SEMICONDUCTORS Challenge is maneuver the band gap:make it sensitive to visible light. 6.3 eV 3.15 eV 1.58 eV U.V 200 nm 400 nm 800 nm Visible TiO2 ZnO CdS WO3 Band gap Energy EMS(λ) TiO2 = 3.20 eV ZnO = 3.35 eV WO3 = 2.80 eV CdS = 2.42 eV Semiconductors are the most ideal and preferred materials.
  27. 27. XRD : DOPED TiO2  XRD analysis confirms the doping of TiO2  Change in lattice parameter ‘a’ & ‘c’ of TiO2,confirms the incorporation of Cd2+ in Ti4+ Influence TiO2 Doped TiO2 Doped TiO2 factor (In-situ) (External) a/nm 3.0301 3.3184 3.3558 c/nm 9.5726 10.0136 11.2138 Intensity(a.u.) Position (2 Theta) 20 30 40 50 60 70 80 External In-Situ method TiO2 market procured TiO2 (Reference)
  28. 28. PARTICLE SIZE ANALYSIS : DOPED TIO2 A particle size of 80 - 87 nm of the doped mixture has been achieved by In-situ methods Doped In-SituDoped ExternalTiO2
  29. 29. THANK YOU

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