Slide 1

Chapter 1 Introduction to Nanomaterials and Synthesis Slide 2 Nanomaterial is a key element of Nanotechnology. Nanotechnology is based on nanomaterials. Nanotechnology does not exist without nanomaterials. A. Nanomaterials and Nanotechnology Slide 3 A technology that deals with small structrues or small-sized materials (with a typical dimension spanning from subnanometer to several hundred nanometers.) B. Nanotechnology - A nanometer (nm) is one billionth of a meter, or 10 -9 m. - 1nm 10 hydrogen or 5 silicon atoms aligned in a line. A technology of designing, fabrication and applications of nanostructures and nanomaterials. Fundamental understanding of physical properties and phenomena of nanomaterials and nanostructures. Study on fundamental relationships between physical properties and phenomena and material dimensions in the nanometer scale. F1.123 Slide 4 C. Nanomaterials Materials with at least one dimension falling in nanometer scale or with nano-sale structures. Types of nano materials - Zero-dimensional nanomaterials: nanoparticles or nano powder - One-dimensional nanomaterials: nanofibers, nano wires, nonobelts, nanotubes and nanorods. F3.14F3.19 F4.7F4.14F4.23F4.29 - Two dimensional nanomaterials: Thin films, nano flakes, nano platelets nanosheets and nano coatings. - Three-dimensional nanomaterials: Monolithic, bulk made of nanoscale building blocks or consisting of nanoscale structures. F.1 F.3 F.8 Slide 5 Properties of Nanomaterials Materials in the micrometer scale mostly exhibit physical properties the same as that of bulk form; materials in the nanometer scale may exhibit properties distinctively different from that of bulk: a lower melting point (the difference can be as large as 1000 ); reduced lattice constants; band gap broading; (e.g., semiconductors become indulators;) exhibit catalytic properties(e.g., nano Au particles). 9F.8-13F.8-15 F.8-22F.8-24F.8-23 #12#36 Slide 6 In order to explore novel physical properties and phenomena and realize potential applications of nanostructures and nanomaterials, the ability to fabricate and process (synthesis and processing) nanomaterials and nanostructures is the first corner stone in nanotechnology. D. Nanomaterial and Synthesis Slide 7 E. Some applications of Nanomaterials Zero-dimensional nano materials: Nanoparticles or nano powder One-dimensional nano materials: Nanofibers, Nano wires, and Nanorods. Two-dimensional nano materials: Thin films, nano flakes, nano platelets nanosheets and nano coatings. Three-dimensional nano materials: Monolithic, bulk made of nanoscale building blocks or consisting of nanoscale structures. I11DSC 22102 ABCD 147 148 Fig1 F.8BNgraphene #13 Pervoskite #40 Slide 8 0.1mm Nano size Slide 9 Zero-dimensional nano materials (classification of powders according to size) powder (particles) Molecular cluster 0.001m0.01m0.1m1m 1nm10nm100nm1000nm d < 100nm : nano powder (particles) ultra fine powder (particles) d < 1m: submicron powder (particles) fine powder (particles) nano powder (particles) submicron powder (particles) microsized particles Slide 10 4. Cathode: 1.Absorption 2. Electron injection 3. Regeneration Dye-Sensitized Solar Cells mechanism Our research goals to synthesize various nanopowder and nanostructured materials (TiO 2, ZnO,CeO 2 ) with different morphologies for the fabrication of semiconductor electrode for DSSCs. Requirement: semiconductor thin film. high specific surface area energy levels matching the dye molecules and the electrolyte (LAMA, NCKU) Slide 11 Slide 12 Nano-catalyst requirement: high specific surface area Nano-sized D Slide 13 SCS sol directly spin-onto FTO-glass scs P25 700nm P25 6.4m #13 (LAMSA, NCKU) Slide 14 Slide 15 (C) Multilayer Ceramic Capacitor A capacity size objectives : smaller size higher capacity Slide 16 B (internal electrode) (dielectric material) (external electrode) Slide 17 Nano-sized dielectric ceramic powder C MLC (multilayer capacitor) present technology: size 1mm number of layer 1000 layer spacing 1m thin and small low temperature sintering Slide 18 Flat Panel Display (with CNT emitter) (phosphors) (carbon nano tube) Advantages: low energy consumption high resolution thin device dimension Slide 19 F3.14 Slide 20 F3.19 Slide 21 F4.14 Slide 22 F4.7 Slide 23 F4.23 Slide 24 F4.29 Slide 25 F.1 Characterization of BN nanosheets. (a) SEM image of laterally large BN nanosheets. The inset is a BN product of around 100 mg in weight obtained during a single experimental run. (b) A magnified image of an ultra-thin BN nanosheet. (c) TEM image of plentiful BN nanosheets which were dispersed in ethanol. The inset is a selected magnified image showing a detailed folded corrugation landscape. (d) HRTEM image of a six-layered BN nanosheet. The inset image is a zoomed-in picture indicating a perfect honeycomb-like BN crystal lattice. The inset profile is the corresponding EELS of BN nanosheets. (e) AFM tapping mode image of two pieces of large BN nanosheets. (f) 3D view of the marked region in (e). (g) Cross- sectional profile along the scan marked in (e) and (f). Slide 26 F.3 Slide 27 Cell separation using magnetic nanoparticles (antibody) (magnetic nanoparticles) (normal cells) (targeted or infected cells ) (magnetic field) Slide 28 (quantum dot) (cancer cells) (identification species) Cancer targeting using quantum dot (nanoparticles) Slide 29 29 Slide 30 30 Slide 31 Increase in Band gap forbidden region discrete energy level Bad gap density of energy level Energy nanocrystal nanowire thin (nano) film bulk crystal Slide 32 Slide 33 Slide 34 Zero-dimensional nano materials (classification of powders according to size) powder (particles) Molecular cluster 0.001m0.01m0.1m1m 1nm10nm100nm1000nm d < 100nm : nano powder (particles) ultra fine powder (particles) d < 1m: submicron powder (particles) fine powder (particles) nano powder (particles) submicron powder (particles) microsized particles 9 Slide 35 Slide 36 #36 Slide 37 (LAMSA, NCKU) #7 #4 Slide 38 BN: as a carrier for drug delivery BN has a layered structure similar to graphite. Dopamine is a neurotransmitter which plays an important party in the neural system in human body especially in the brain. In the brain, dopamine is released by nerve cells to act as intermediate to send signals to other receptors. This is why this compound has a critical role in learning ability, memory function, controlling the noise tolerance as well as adjusting the personal character. Required properties: chemically inert nontoxic high drug adsorption BN Slide 39 Graphene is one planar sheet of sp2 -bonded carbon atoms arranged in a hexagonal lattice and is the basis of carbon nanotubes The importance of graphene sheets has been demonstrated in a variety of applications including high electron mobility, and the enhancement of mechanical and electrical properties of composite materials. graphene Slide 40 #40 The structure of BN Slide 41 Slide 42 Slide 43 Perovskite Solar Cell Perovskite structure(ABX3) Ex:CH3NH3PbX3 (X = Cl,Br, I) CH3NH3PbI3-xClx Device architecturestem from DSSC TiO2 compact layer (hole transport material) Au: counter electrode HTM: hole transport CH3NH3PbI3: absorber mesoporous-TiO2: scaffold, electron transport TiO2 compact layer: block the contact between HTM and FTO light Pervoskite