nanoparticle production

SelectedNanopar.cleResearchandFiberOp.cProduc.onProcesses

StevenBurrowsVirginiaTech

MorrisResearchGroup

2

Hemisphericalcollectorsurfaceinuse(TiO2). CondensedfilmofTiO2.

Shimstockcollectorsurfaceinuse(TiO2).

UsedTiO2targetpellets.

Laserop.calsystem.

A B

C

D

E

LaserVaporiza.on–Condensa.onNanopar.cleSynthesis

3

UreaHydrolysisAuDeposi.ononEvonikP25TiO2

A

B

C

4

FAN

FAN

Heated Sand Bath

Air-cooled reflux condenser tubes

Aluminum air duct tube

Air FlowAir Flow

Stirrer Motors

Note the removeable top and sliding air ducts for connection to the condenser duct.

UreaHydrolysisAuDeposi.ononEvonikP25TiO2

UreaHydrolysisGoldDeposi4onCO(NH2)2(aq)+3H2O(l)→CO2(g)+2NH4OH(aq)

pH3at30∘CtopH8atT~80∘CHAuCl4(aq)+4NH4OH(aq)→Au(OH)3(s)+4NH4Cl(aq)+H2O(l)

UreaHydrolysisGoldDeposi4onCO(NH2)2(aq)+3H2O(l)→CO2(g)+2NH4OH(aq)

pH3at30∘CtopH8atT~80∘CHAuCl4(aq)+4NH4OH(aq)→Au(OH)3(s)+4NH4Cl(aq)+H2O(l)

5

PreformFabrica.onGaseousReactantMixingSystem

MFC

Digital Scale(Networked)

O2 Carrier

MFC

Digital Scale(Networked)

O2 Carrier

MFC

Digital Scale(Networked)

O2 Carrier

SiCl4 GeCl4 POCl3

MFC

O2 Makeup

MFCHe

MFCBCl3

Temperature Controlled Enclosure

to Process

to ControlComputer

MFC = Electronic Mass Flow Controller

MixingManifold

LiquidVaporization

Spargers

Mobile H2 / O2Torch Bank

ReactionZone

SinteredGlassLayer

Wall-DepositedOxide "Soot" Particles

Waste "Soot" and Cl2 (g)

SiCl4 (g)GeCl4 (g)POCl3 (g)

BCl3 (g)O2 (g)

Reactants:

Mobile H2 / O2Torch Bank

Cl2 (g)

Substrate Tube

Vapor-DepositedSubstrate Tube

CollapsedPreform Rod

Vapor-deposited glass layers at rod center

Fiber Optic Preform Rod Quartz Handle Rod

PreformFabrica.on:ChemicalVaporDeposi.on(CVD)

Internaldeposi.onofmul.pledopedSiO2layersinquartzsubstratetube.

Collapseofinternallycoatedsubstratetubetosolidpreformrod.

Finishedpreformrodonquartzhandle.

1

2

36

"Soot" Deposition Torch

SiCl4 (g)GeCl4 (g)POCl3 (g)

BCl3 (g)O2 (g)

Reactants:

CH4 (g)O2 (g)

GlassMandrel

He(g), Cl2 (g)

Heating Element

OxideParticles

Fiber Optic Preform Rod Quartz Handle Rod

"Soot" Preform

"Soot" Preform

Torchdeposi.onofflamehydrolyzedpar.clesontodopedSiO2mandrel.

Dehydra.onof“soot”preformwithHe,Cl2andsinteringtovitreousrod.

Finishedpreformrodonquartzhandle.

1

2

3

PreformFabrica.on:OutsideVaporDeposi.on(OVD)

7

DrawingOp.calFiberfromPreformRods

•  Preformfeedspeedissetataconstantrate.

•  Thefurnacemaybe:–  GraphiteResistance–  RF–CoupledZirconiaMuffle–  InfraredLaser

•  ThecapstanspeedislinkedtotheuncoatedfiberdiameteratLaserMicrometer1.

•  Thefibercoa.ngsystemmayinclude:–  ExtrudedThermoplas.cs–  RTVSilicone–  UV-curedAcrylate

Furnace

Preform Rod

PreformFeedMechanism

Laser Micrometer 1

Laser Micrometer 2

MotorizedCapstan

CoatingExtruder

TakeupSpool

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