Nanomaterials - Synthesis And Characterization
Nanomaterials - Synthesis andCharacterizationDr. Abdul kadir MasromGeneral ManagerNanotechnology Focal Point, SIRIM Bhd
Contents Introduction Definition Standard terminology Classification –Nanomaterials Properties andcharacteristics ofnanoparticles Nanomaterial synthesistechniques NanomaterialsCharacterization Environmental, Safety andHealth Aspect
Nanostructure EngineeringAtoms/moleculesNano-particles, wires,and tubes, etcNatural andSynthetic nanoelectronicsseparation, & healthcareBioMEMs, optical displays,sensors and biochipsApplicationsChemical SynthesisSelf-assemblySTM & AFM Based LithographyElectron, Ion-beam LithographyNanoimprint LithographyPhotolithographyInk-jet PrintingMicro machiningFabrication PlatformsNano Materials and Technology is a multidisciplinary platform.
Introduction Nanoparticles – not new –dated back to fourth century– damascus blade, romancolored glass, Chinese Inkbut nanotechnology andnanoscience are new They new the effect – butthey cannot explain whatcaused the effectWHY?
Why Nano so exciting? What is actually so exciting about “nano”? “Nano” means one billionth (10-9), so 1 nanometerrefers to 10-9 meter and is expressed as 1 nm. 1 nm is so small that things smaller than it can onlybe molecules, clusters of atoms or particles in thequantum world.ISO TC229-JWG1
Why is nanotechnology important?US Interagency Working Group on Nano Science, Engineering and Technology(IWGN) workshop on Nanotechnology Research Directions (Sept. ’99):“nanotechnology will be a strategic branch of science and engineering for the 21st century,one that will fundamentally restructure the technologies currently used formanufacturing, medicine, defence, energy production, environmental management,transportation, communication, computation and education.”US NSF report on “SOCIETAL IMPLICATIONS OF NANOSCIENCE ANDNANOTECHNOLOGY” March 2001:“the impact of nanotechnology in the 21st century is likely to be at least as significant forhealth, wealth and security as the combined influences of antibiotics, integrated circuitsand polymers.”Projected world-wide market for n-t enabled productswill be between 500 billion and 3 trillion by 2015“It is estimated that Nanotechnology is presently at a levelof development similar to that of computer/informationtechnology in the 1950s” (Nanostructure Science andTechnology: A Worldwide Study, WTEC Panel report,1999)
Nanotechnology Fieldnanotechnologies nanoscale electronicdevices
itionNanoparticlesNanomaterialsNanoscience
Definition of nanoscience andnanotechnology Earliest definition given by the USNationalNanotechnology Initiative (NNI): nanoscience and –technology are “Research and technologydevelopment at the atomic, molecular and macromolecularlevels in the length scale of approximately 1-100 nanometerrange, to provide a fundamental understanding ofphenomena and materials at the nanoscale and to create anduse structures, devices and systems that have novel propertiesand functions because of their small and/or intermediatesize”. Simply saying, nanoscience tells us how to understand the basictheories and principles of nanoscale structures, devices andsystems (1-100 nm); and nanotechnology tells us what to do andhow to use these nanoscale materials.
ISO Definition-STD definitionNanoscale - size range from approximately 1 nmto 100 nmNOTE 1 Properties that are not extrapolations from a larger size will typically,but not exclusively, be exhibited in this size range. For such properties the sizelimits are considered approximate.NOTE 2 The lower limit in this definition (approximately 1 nm) is introduced toavoid single and small groups of atoms from being designated as nano-objectsor elements of nanostructures, which might be implied by the absence of alower limit.
Core Term - Definitions Nanomaterial: material having a geometric or structural feature in thenanoscale–NOTE Examples include nanocrystalline materials, nanoparticle powder, materials with nanoscale precipitates, nanoscale films,nanostructured objects, nano-porous objects, and materials with nanoscale textures on the surface.
Supporting definitions defined in ISO/TS 27687:2008,Nanotechnologies -- Terminology and definitions for nano-objects -Nanoparticle, nanofibre and nanoplate Nano-object: material with one, two or threeexternal dimensions in the nanoscale. NOTE Generic term for all discrete nanoscale objects. Nanostructured material: material with an externaldimension larger than the nanoscale having an internalor surface structure at the nanoscaleNanoparticle: nano-object with all three externaldimensions in the nanoscale.NOTE If the lengths of the longest to the shortest axes of the nano-object differsignificantly (typically by more than three times), the terms nanorod or nanoplateare intended to be used instead of the term nanoparticle.
Working definitions reached by PG5 Nanotechnology: the application of scientific knowledge tocontrol and utilize matter at the nanoscale, where size-relatedproperties and phenomena can emerge. Nanoscience: the systematic study and understanding of matter,properties and phenomena related to the nanoscale. nanoscale properties: properties related to the nanostructureof a given material or device.
Working definitions reached by PG5 (Cont.) Nanoscale phenomena: phenomena occurring at the nanoscale wherequantum confinement applies. Nanosystem: a set of objects or components arranged or organized for aspecific function, with at least one dimension of the system at the nanoscale. Question. Must a “nanosystem” function as a system at the “nanoscale” or is it a nanosystemif just one component of the system functions at the nanoscale, yielding a purpose at alarger-than-nano scale? Nanodevice: an object or component designed for a purpose, with at leastone dimension at the nanoscale.
Nanotechnology Standard –Terminology and Nomenclature ISO -TC229 IEC - TC113 OECD – Working Party on Manufactured Nanomaterials(WPMN) CEN
Map of current and potential liaisons for ISO/TC 229ISO/TC 119MATERIALSISO/TC 107Metallic andother inorganiccoatingsPowdermetallurgyISO/TC 206PackagingFine ceramicsOECDWPNEU JRCInstitute for Healthand ConsumerProtectionandIRMMPlasticsISO/TC 84Devices foradministration ofmedical products andintravascularcathetersISO/TC150Implants forsurgeryNanotechnologyASTM E56CEN/TC 352Nanotechnology Standardizationfor electricalNanotechnologiesand electronicproducts andsystemsAsia NanoForumISO/TC 61ISO/TC 217CosmeticsIEC/TC 113ISO/TC 91Surface activeagentsISO/TC SOECDWorking Party onManufacturedNanometerialsRISK/HS&EISO TC 229ISO/TC 24ISO/TC 38TextilesISO/TC 94Personal safety –Protective clothingand equipmentISO/TC 35Paints andvarnishesNANOPARTICLESISO/TC 147Water qualityISO/TC 34Food productsISO/TC 48LaboratoryequipmentISO/TC 209Clean rooms andassociatedcontrolledenvironmentsISO/TC 172Optics andphotonicsISO/TC 213Dimensional andgeometrical productspecifications andverificationMETROLOGY ANDCHARACTERIZATIONISO/TC 146Air qualityISO/TC 47ISOChemistryREMCOISO/TC 184Industrialautomationsystems andintegrationISO/TC 203Technicalenergy systemsISO/TC 212Clinical laboratorytesting and in vitrodiagnostic testsystemsISO/TC 194Biologicalevaluation ofmedicaldevicesVAMASSieves, sieving andother sizing methodsISO/TC 168Prosthetics andorthoticsISO/TC 212Clinical laboratorytesting and in vitrodiagnostic testsystemsISO/TC 59BuildingconstructionBIOMEDICALISO/TC 202Micro-beamanalysisISO/TC 201SurfacechemicalISO/TC 135 analysisNondestructivetestingISO/TC 180ISO/TC 215HealthInformaticsISO/TC 225Marketopinion andsocialresearchISO/TC 215EnvironmentalmanagementISO/TC 28Petroleum andpetroleumproductsSolar energyENERGY
Needs for standardization1.2.3.To support commercialisation and market developmentTo provide a basis for procurement through technical requirements, and quality andenvironmental managementTo support voluntary governance structures and appropriate legislation and regulationChallenges: currently there are:No internationally agreed terminology/definitions for nanotechnology(ies). No internationally agreed protocols for toxicity testing of nanoparticles. No standardized protocols for evaluating environmental impact of nanoparticles. Existing “methods of test” might not be suitable for nanoscale devices and nanoscale dimensions. Measurement techniques and instruments need to be developed and/or standardized. New calibration procedures and certified references materials are needed for validation of testinstruments at the nanoscale. Multifunction nanotechnology systems and devices will need new standards.Partial solutions Some existing standards are or might be applicable e.g. for chemical analysis and imaging (ISOTCs 201 and 202) and particle detection/sizing (ISO TC 24)
ISO/TC 229 JWG1: Strategic RoadmapProject 3Terminology –nano-biointerfaceBaseDefinitionsNanomaterials classificationNanoscaleProject 4NanoscaleattributeProject 1NanoprocessesNano filmsTerminology –carbonnanostructuresTerminology nanoparticlesNomenclature- ModelOptionsNanoscale Framework and coretermsTerminology nanofabricationComplexassembliesProject 2NanodispersionsNanostructuredmaterialsTerminology nanomaterialsTerminology nanostructuresNomenclature yNanomeasurementtoolsTerminology – nanoscalemeasurementTerminology –medical andconsumerNanophotonicdevices(IEC) Terminology –nano-opticsNanosensorsDevices y electrotechnical
Nanomaterials Classification ISOTC229-Classification OECD – engineered and accidental Nanoparticles – WG1 ISO-TC229
A1NanocompositesA2Nanoporous materialsA3Nanocrystalline sB3DendrimersC1Nanofilms and rodsE1NanoclustersE2Quantum oids
dimension1-D nanoparticle array – thin film, grapheneZero-D
Dimension ----Internal/External Structure ------Type ofNanomaterials
Dimension ----Internal/External Structure ------Type ofNanomaterials
Dimension ----Internal/External Structure ------Type ofNanomaterials
Properties and Characteristics Thermal properties Optical properties Mechanical properties Chemical properties
Unique Propertiesat the NanoscaleThe science behindnanotechnologyCopyright 2005 SRI International
Are You a Nanobit Curious? What’s interesting about the nanoscale?– Nanosized particles exhibit different properties thanlarger particles of the same substance As we study phenomena at this scale we – Learn more about the nature of matter– Develop new theories– Discover new questions and answers in many areas,including health care, energy, and technology– Figure out how to make new products andtechnologies that can improve people’s lives
Properties of a Material A property describes how a materialacts under certain conditions Types of properties– Optical (e.g. color, transparency)– Electrical (e.g. conductivity)– Physical (e.g. hardness, melting point)– Chemical (e.g. reactivity, reaction rates) Properties are usually measured bylooking at large ( 1023) aggregationsof atoms or moleculesSources: 6.gif
What does this all means? The following factors are key forunderstanding nanoscale-relatedproperties– Dominance of electromagnetic forces– Importance of quantum mechanicalmodels– Higher surface area to volume ratio– Random (Brownian) motion It is important to understand thesefour factors when researching newmaterials and properties
Size-Dependent PropertiesHow do properties change at thenanoscale?Why do propertieschange?At different scalesDifferent forces dominate Differentmodels better explain phenomena
Optical Properties Example: Gold Bulk gold appears yellow in colorIf you cut a block of gold intosmaller & smaller pieces, it wouldstill look like goldat the nanoscale properties change!“Bulk” gold looks yellow Nanosized gold appears red in color– The particles are so small that electronsare not free to move about as in bulkgold– Because this movement is restricted, theparticles react differently with lightSources: /MNT7/Abstracts/Levi/12 nanometer goldparticles look red
Optical properties The optical properties ofresult from localizedsurface plasmonsThe origin of the color difference in the cup is attributed to theoptical response of colloidal nanoparticles of gold dispersed in theglassnanomaterials differremarkably from bulkmaterials. This difference canbe mainly attributed to thequantum confinementeffects, unique surfacephenomena, and efficientenergy and charge transferover nanoscale distanceswithin nanomaterials.Lycurgus Cup from the 4th century AD
Optical Properties Example:Zinc Oxide (ZnO) Large ZnO particles– Block UV light– Scatter visible light– Appear white Nanosized ZnO particles– Block UV light– So small compared to thewavelength of visible lightthat they don’t scatter it– Appear clearSources: http://www.apt powders.com/images/zno/im zinc oxide reen.jpg“Traditional” ZnOsunscreen is whiteNanoscale ZnOsunscreen is clearZinc oxide nanoparticles
Optical Properties - TiO2 and ZnO Scattering of visible light (whitening effect) isinfluenced by particle size and the differencebetween the refractive index of the pigmentand the surrounding media. WavelengthParticle sizeMaximum scattering occurs whensize equals 1/2 the wavelength andparticles are uniformly dispersed(Mie theory).
TiO2 035151035151010nm TiO2 (110 nm dispersion particle size) makes transparentdispersions for all skin types.www.koboproducts.com
Electrical Properties Example: Conductivityof Nanotubes Nanotubes are long, thin cylinders of carbon– They are 100 times stronger than steel, very flexible,and have unique electrical properties Their electrical properties change with diameter,“twist”, and number of walls– They can be either conducting or semi-conducting intheir electrical behaviorElectric currentvaries by tubestructureMulti-walledSource: http://www.weizmann.ac.il/chemphys/kral/nano2.jpg
Electronic properties As the particle size decreasesbelow the Bohr radius of thesemiconductor material, theelectron becomes more confined in theparticle. This leads to an increasein the band gap energy and thevalence and conduction bandsbreak into quantized energylevels.The band gap emission shown is observed to shift throughthe entire visible region, from red emission for the largestparticles, to blue emission for the smallest clusters. For example the effect ofchanging the particle size of CdSenanoparticles.
Physical Properties Change:Melting Point of a Substance Melting Point (Microscopic Definition)– Temperature at which the atoms, ions, ormolecules in a substance have enough energyto overcome the intermolecular forces that holdthe them in a “fixed” position in a solid– Surface atoms require lessenergy to move because they arein contact with fewer atoms ofthe substanceIn contact with 3 atomsIn contact with 7 atomsSources: http://puffernet.tripod.com/thermometer.jpg andimage adapted from x4.html
Physical Properties Example:Melting Point of a Substance IIAt the macroscaleAt the nanoscaleThe majorityof the atomsare almost all on theinside of the object split between theinside and the surfaceof the objectChanging anobject’ssize has a very smalleffect on thepercentage of atomson the surface has a big effect on thepercentage of atoms onthe surfaceThe meltingpoint doesn’t depend onsize is lower for smallerparticles
Scale Changes Everything II Four important ways in which nanoscalematerials may differ from macroscale materials– Gravitational forces become negligible andelectromagnetic forces dominate– Quantum mechanics is the model used todescribe motion and energy instead of theclassical mechanics model– Greater surface area to volume ratios– Random molecular motion becomes moreimportant
Dominance of Electromagnetic Forces Because the mass of nanoscale objects is sosmall, gravity becomes negligible Gravitational force is a function of mass anddistance and is weak between (low-mass)nanosized particlesElectromagnetic force is a function of chargeand distance is not affected by mass, so it canbe very strong even when we have nanosizedparticlesThe electromagnetic force between twoprotons is 1036 times stronger than thegravitational force!Sources: http://www.physics.hku.hk/ nature/CD/regular ntonine-education.co.uk/Physics AS/Module 1/Topic 5/em force.jpg
Quantum Effects Classical mechanical models that weuse to understand matter at themacroscale break down for – The very small (nanoscale)– The very fast (near the speed of light) Quantum mechanics betterdescribes phenomena that classicalphysics cannot, like – The colors of nanogold– The probability (instead of certainty)of where an electron will be foundSources: http://www.phys.ufl.edu/ ://www.nbi.dk/ pmhansen/gold trap.ht; n-hccncsq5.jpg;MacrogoldNanogold
Surface Area to Volume Ratio Increases As surface area to volumeratio increases– A greater amount of asubstance comes in contactwith surrounding material– This results in better catalysts,since a greater proportion ofthe material is exposedfor potential reactionFigure - Calculated surface to bulk ratios for solid metal particlesversus size.39 The % of surface atoms increases while the % ofbulk atoms decrease when going to nanometer scales.Source: ceVol0.gif
Random Molecular Motion is Significant Tiny particles (like dust) moveabout randomly– At the macroscale, we barely seemovement, or why it moves– At the nanoscale, the particle ismoving wildly, batted about bysmaller particles Analogy– Imagine a huge (10 meter) balloon being batted about bythe crowd in a stadium. From an airplane, you barely seemovement or people hitting it; close up you see the balloonmoving wildly.Source: ics/brownian motion/rand path.gif
Surface Plasmon ResonanceSurface plasmon resonanceApplication of SPR Surface analysis sensor- Oscillation of free electronson metal surface at polarizedelectromagnetic radiation- E-band was changed byreflective index of near region- Detection of index change inrefractive of medium- Non-labeling detection tool- Protein detection 10-9 10-10- Small molecules X ( 1 kDa)
Sensitivity enhancement of SPR signalNovel SPR sensor chipGold layerprism* Fabrication of nanostructureSPR sensor chipImage processingFabrication of nanostructureAu evaporation나노 구조체 제조Well-orderd 2D colloidal filmSilica particle removeA thin layer was depositedPeriodic nanostructure
Magnetic properties Study of magneticproperties of nanoparticlesin the size range of 1-100nm is an important area applications such asmagnetic resonanceimaging (MRI) formedical diagnosis, highdensity magneticrecording, magneto-opticalswitches, therapeutic andcontrolled drug delivery.
Synthesis Technique Top-Down Bottom-up
Method for Synthesis of Nanomaterials How to get at nano scale? Top–down or bottom–up? What is top-down approach? What is bottom-up approach?UltimateGoal:Dial in the properties that you want bydesigning and building at the scale of nature(i.e., the nanoscale)
Reactant 1 Reactant 2SonochemistryMicrowavesynthesisT, p, tProduct HydrothermalmethodsSol-gelmethodsWet chemicalco-precipitationMicroencapsulation
How to get at nano scale There are two general approaches to the synthesis ofnanomaterials and the fabrication of nanostructuresBottom-up approachThese approaches include theminiaturization of materialscomponents (up to atomic level) withfurther self-assembly process leadingto the formation of nanostructures.During self-assembly the physicalforces operating at nanoscale are usedto combine basic units into larger stablestructures.Typical examples are quantum dotformation during epitaxial growth andformation of nanoparticles fromcolloidal dispersion.Top-down approachThese approaches use larger(macroscopic) initial structures,which can be externally-controlled in theprocessing of nanostructures.Typical examples are etching throughthe mask, ball milling, and application ofsevere plastic deformation.
Bottom-up methodsTop-down methods start with atoms or begin with a patternmolecules and build upgenerated on a largerto nanostructuresscale, then reduced tonanoscale. Fabrication is much lessexpensive By nature, aren’t cheapand quick to manufacture– Slow and not suitable forlarge scale production.
Top-down versus Bottom-up
Bottom-up Process - What to control Colloidally stable nanoparticles Reproducible Adaptable surface properties Easy cheap (Biocompatible or biodegradable systems)
Gaseous Phase Method Principal: Gas –phaseprecursors interact with aliquid–or solid-phase materialGas state condensationChemical vapor depositionMolecular beam epitaxyAtomic layer depositionCombustionThermolysisMetal oxide vapor phaseepitaxyIon implantation
Liquid Phase Fabrication Method Molecular self-assemblySupramolecular chemistrySol-gel processesSingle-crystal growthElectrodeposition /electroplatingAnodizingMolten salt solutionelectrolysisLiquid template synthesisSuper-critical fluid expansion
Liquid Phase Synthesis Precipitating nanoparticlesfrom a solution of chemicalcompounds can be classifiedinto five major categories: (1)colloidal methods; (2)sol –gel processing; (3) water –oil microemulsionsmethod; (4) hydrothermal synthesis;and (5) polyolmethod.
Sol-Gel ProcessThe sol is a name of a colloidal solution made ofsolid particles few hundred nm in diameter,suspended in a liquid phase.The gel can be considered as asolid macromolecule immersedin a solvent.Sol-gel process consists in the chemicaltransformation of a liquid (the sol) into a gel stateand with subsequent post-treatment and transitioninto solid oxide material.The main benefits of sol–gel processing are the highpurity and uniform nanostructure achievable at lowtemperatures.
Sol-Gel Process Start with precursor Form Solution (e.g.,hydrolysis) Form Gel (e.g.,dehydration) Then form finalproduct Aerogel(rapid drying) Thin-films (spin/dip)In solgel chemistry, molecular precursors are converted tonanometer-sized particles, to form a colloidal suspension, or sol.Adding epoxide to the sol produces a gel network. The gel can beprocessed by various drying methods (shown by the arrows) todevelop materials with distinct properties.
Advantage & Disadvantage – Sol-Gel Method
Sonochemical Reaction and Synthesis Sonochemistry is the application ofultrasound to chemical reactions andprocesses. The mechanism causingsonochemical effects in liquids is thephenomenon of acoustic cavitation. Schematic representation of the reactive regions of a collapsingcavitation bubble.[Ultrasound] causes cavitation whichcauses local extremes of temperatureand pressure in the liquid where thereaction happens.*It breaks up solids and removespassivating layers of inert material to give alarger surface area for the reaction to occurover.*Biological cells including bacteria can bedisintegrated.“Experimental results have shown thatthese bubbles have temperatures around5000 K, pressures of roughly 1000 atm These cavitations can create extremephysical and chemical conditions inotherwise cold liquids.”*
Sonochemical Nano-Synthesis Sonochemistry: molecules undergo a chemical reaction due toapplication of powerful ultrasound (20 kHz – 10 MHz)– Acoustic cavitation can break chemical bonds– “Hot Spot” theory: As bubble implodes, very high temperatures ( 5,000 –25,000 K) are realized for a few nanoseconds; this is followed by very rapidcooling (1011 K/s)– High cooling rate hinders product crystallization, hence amorphousnanoparticles are formedSuperior process for: Preparation ofamorphous products Insertion of nanomaterials intomesoporous materials Deposition ofnanoparticles on ceramicand polymeric surfaces
Sonochemical Nano-Synthesis: Examples Gold, Co, Fe, Pg, Ni, Au/Pd, Fe/Co Nanophased oxides (titania, silica, ZnO, ZrO2, MnOx– More uniform dispersion, higher surface area, better thermal stability, phasepurity of nanocrystalline titania reported MgO coating on LiMn2O4Magnetic Fe2O3 particles embedded in MgB2 bulkNanotubes of C, hydrocarbon, TiO2, MeTe2Nanorods of Bi2S3, Sb2S3, Eu2O3, WS2, WO2, CdS, ZnS, PbS, Fe3O4RMK9 Science Fund: Development of Novel Production ofnanometal and nanometal oxide by high intensity ultrasoundapproach.nanometals: Au, Ag, CoNano metaloxide: TiO2, Fe2O3
Experimental set-up forsonochemistry experimentsAu(left) & Co(right) nanopraticles produced in SIRIM bysonochemical method
Nanorods (or Nanowires) SynthesisTechniques can be grouped into two categories: Spontaneous growth:- Evaporation condensation- Dissolution condensation- Vapor-Liquid-Solid growth (VLS)- Oxide-Assisted Growth (OAG) Template based synthesis:- Electrochemical deposition- Surface Step-Edge Templates
Template Based SynthesisGeneral Aspects: Simple, versatile, easy to control technique Fabricates various materials; polymers, metals, semiconductors,and oxides on a single structure. Porous membrane with nano-size channels (pores) areused as templates Pore size ranging from 10 nm to 500 nm can be achieved.
Template Based synthesisElectrochemical Deposition This is a self-propagating process. This method is an electrolysis in a pre-formed spaceresulting in the deposition of solid materials on an electrode. Only applicable to electrically conductive materials: metals,alloys, semiconductors, and electrical conductive polymers.
Template Based synthesisElectrochemical DepositionElectric fielddirectiongrowth speciesporousmembrane The diameter of the nanowires is determined by thegeometrical constraint of the pores. Fabrication of suitable templates is a critical step. By careful removal of the template, free standingnanowires can be fabricated.
Template Based synthesisElectrochemical Deposition Electrolysis (or electroplating) Upon external field is applied, the process can be reversed orelectrical energy converts to chemical potential - electrolysis Cathode - to be plated (NW fabrication), reduction (working electrode) Anode – plating metal (Ag), oxidation, Noble metals are often usedas an inert electrode (counter electrode)Electroplating:requires a redoxprocess in anelectrochemical cell
Template Based synthesisElectrochemical Deposition nanorods from 200 nm AAO templateS-H Park, J-H Lim, S-W Chung, Chad A. Mirkin, Science,2004 303 348-351
Template Based synthesisElectrochemical Deposition Elements can be ElectrodepositedHHeLi BeBCNOFNA MgAlSiPSCl ArK Ca Sc TiRb SeYVNeCr Mn Fe Co Ni Cu Zn Ga Ge As Se Br KrZr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb TeCs Ba Lu Hf Ta W Re Os IrIXePt Au Hg Tl Pb Bi Po At RnFr Ra Ac Elements plateable from aqueous solutions (red background). Elements with yellow background are only plateablein combination with one of the others (alloy plating).
Template Based synthesisElectrochemical Deposition Typical metal electroplating solution conditions Pd- PdCl2 (1.5 g/L) Disodium ethylenediaminetetraacetate (Na2-EDTA · 2H2O, 40.1 g/L) NH3·H2O (28%, 195mL/L) N2H4 (1 M, 5 mL/L) Ag- Solution A: AgNO3 (2 g/L) Na2-EDTA· 2H2O (60 g/L) Isopropyl alcohol (88 mL/L) Acetic acid (12 mL/L) NH4OH (400 mL/L)- Solution B: Hydrazine (3 mL/L) Mercerine (2 mL/L) Ethanol (400 mL/L) Mixture solutions of A and B at 1:1 (v/v) Au- KAu(CN)2 (5 g/L) KCN (8 g/L) NaOH (20 g/L) Glycine (10 g/L) NaBH4 (25 g/L) Cu- Solution A: CuSO4 (30 g/L) Sodium potassium tartrate (Rochelle salt, 140 g/L) NaOH (40 g/L)- Solution B: Aqueous formaldehyde solution (37.2 wt %)mixture solutions of A and B at 10:1 (v/v) Ni- NiSO4·6H2O (15 g/L) H3C6H5O7·6H2O (18 g/L) NaH2PO2·H2O (30 g/L) NaCH3COO·3H2O (28 g/L) Latic acid (85%, 20 mL/L) Thiourea (2 mg/L)
Template Based synthesisTemplate Construction Common templates:- Porous alumina, nanochannel glass, ion track-etchedpolymers, mica films, di-block copolymers Porous alumina is fabricated by electrochemicalHoneycomb model structureof anodic porous alumina.etching of aluminum using under various acids Pore diameter controlled by potential and acidconcentration- 10 nm 500 nm-109 1011pores/cm2Voltages and correspondingcell diametersSachiko Ono, Makiko Saito, Hidetaka Asoh Electrochimica Acta 2005 51 827–833
Template Based synthesisTemplate synthesisExperimental set up for Fabrication Anodizing Electro pply(2)Stirrer Removal of porous alumina layerCirculator
Properties and Application of NR (or NW)Electrochemical Deposition MaterialsMetalAu (H2O 20 ml 50 mM KAg(CN)2 0.25 M Na2CO3(pH 13)),Ag (H2O 20
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