objective

1

The Development of Mechanically & Electrically CNF & CNF Reinforced Composite

Imran Syakir Mohamad

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Objective

To develop high mechanically & electrically CNF and CNF reinforced composite using various substrates and catalysts

3

Scope

To identify and evaluate several type of commercially available substrate

Inorganic-based (carbon cloth, fiberglass, silica, etc)Plastic-based (polystyrene, nylon, polypropylene, etc)

To develop catalysts for carbon-growth process (cracking of carbon-carbon bond)

3 monometallic catalysts2 bimetallic catalysts

4

Scope

To develop methodology for grafting of catalyst onto the substrate

Identify suitable metal salt solution or metalCondition of grafting for:

Deposition method (pH, temperature, concentration)Sputtering method (radio frequency, time)

To grow nanocarbon onto the catalyst grafted substrate using a few technique

FCCVDPECVD

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Scope

All samples will be characterized for their:

Compositional Analysis (EDX, XRF)Morphology/Structure Analysis (FESEM, HRTEM)Texture/Surface Area Analysis (BET)Functionality (Raman, UV-Vis)Mechanical & Electrical Properties Analysis

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Applications

Energy storageHave intrinsic properties. Can be used as an electrode in batteries & capacitorVery high surface areaGood electrical conductivityTheir linear geometry makes their surface highly accessible to the electrolyte

Use as gases and ions transport media

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Applications

Air, Water and Gas Filtration

these filters can not only block the smallest particles but also kill most bacteria

Structural compositeGood mechanical properties, such as stiffness, toughness, strength and lightweight.Possible to replace commercial fiber (e.g.Fiberglass)

COMMERCIAL AIR FILTRATION CARTRIDGEUSING NANOFIBER FILTER MEDIA

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Challenges

Economic & reasonable cost, high productionWell homogeneous catalyst dispersionStrong vertical align CNF attachment onto the substrate (inside the pore)Enhance CNF properties (mechanical, electrical, thermal)Control the CNF characteristic (diameter, length)

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Substrate Proposed:

Inorganic-based (Carbon Cloth)Plastic-based (Polypropylene)

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Carbon Cloth as a Substrate

ReasonHigh microporosityHigh surface area (>1000 m2/g)Excellent adsorbent in gas & liquid mediaWell establish/commercialNarrow fiber diameter (10-20 micron)

Offer more catalytic propertyOffer more adsorption ability

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Carbon Cloth

E-TEK CC SpecificationsWeave = PlainWeight = 116 g/m2

Thickness = 0.35 mmSize = 25 cm x 25 cmContent = 99 % carbon, 1 % ashPrice = $43.75

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Catalyst Proposed (FCCVD)

3 monometallic: Fe, Ni, Cometallocene as a catalyst precursors

FerroceneNickeloceneCobaltocene

2 bimetallic which are combination of two monometallic

Fe-CoNi-Fe

Fe NiCo

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Metallocene as Catalyst Precursor

Why choose metallocene?Catalyst size – main important for CNF formation.

Nanosize cat. particles catalyze CNF growth

Metallocene chosen because easy to vaporize at lower temp. (faster & simple process)

Vaporize metallocene molecule carried to reaction tube by H2 gas and C2H4.

Reduce by H2 to form Fe atom & deposite onto substrate.

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Catalyst Proposed (PECVD)

3 monometallic: Fe, Ni, CoMetal salt as a precursors

Iron nitrate, FeNickel nitrate, Ni(NO3)2.6H2O

Cobalt nitrate, Co

2 bimetallic which are combination of two monometallic

Fe-CoNi-Fe

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Technique Proposed

FCCVDFloating Catalyst Chemical Vapor Deposition

Best for high productivityHigh potential application in industry

PECVDPlasma Enhanced Chemical Vapor Deposition

Best to synthesize vertical aligned CNFLow temperature deposition

PECVD

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Experimental Route (FCCVD)

Washing(removes impurities;

eg: Al, Si, Fe, K)


eg: Al, Si, Fe, K)

Catalyst Development


Nanocarbon Growth

Nanocarbon Growth

CharacterizationCharacterization• Monometallic• Bimetallic

• Monometallic• Bimetallic

• Compositional analysis (EDX,XRF)

• Morphology/Structure analysis (SEM, HRTEM)

• Texture/Surface Area analysis (BET)

• Functionality (Raman)• Mechanical & Electrical

Properties Analysis





Properties Analysis

• Carbon source (C2H4)

• Carrier gas (H2 & N2)

• Additive (Thiophene, H2S)


• Carrier gas (H2 & N2)

• Additive (Thiophene, H2S)

Substrate (CC)

Substrate (CC)

TreatmentTreatment

CNFCNF

CNF After TreatmentCNF After Treatment

Polymer (PP)

Polymer (PP)

CNF Reinforced

CNF Reinforced

• treat with HNO3, T=30oC, 24 hr

• wash with deionized water (1L), dried T=200oC, 2 hr



• Use acid treatment (HCl) to remove catalyst & amorphous C.


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Setup (FCCVD)

Schematic Diagram of a FCCVD system

Heating coil

Catalyst

Furnace

Substrate

H2 N2

Outlet

Stainless steel tube

C2H4

Mass flow meter

Thiophene

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Growth Condition (FCCVD)

Process Calcination Reduction Growth Cooling

Sources N2 N2+H2 H2+C2H4 N2

Temp 250oC 300oC 600oC RT

Composition

5% N2 20% C2H4

Time 1 hr 1 hr 2 hrs

To enhanced the catalytic activity

Catalyst deposition

Idea: Replace H2 with NH3.

WHY?

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Aligned CNT was obtained in NH3 and N2 environment

Synthesis conditionCNT

Morphology Citationmethod

Temperatue(oC) Reaction Gas Catalyst

PE-CVD 666 C2H2+NH3 Ni Aligned CNT Science 282, 1105 (1998)

PE-CVD 660 C2H2+NH3 Ni Aligned CNT APL 75 1086 (1999)

PE-CVD 825 C2H2+NH3 Co Aligned CNT APL 77 830 (2000)

Thermal-CVD 750~950 C2H2+NH3 Fe Aligned CNT APL 77 3397 (2000)

PE-CVD 825 C2H2+NH3 Co Aligned CNT APL 77 2767 (2000)

Thermal-CVD 800 C2H2+NH3 Fe Aligned CNT APL 78 901 (2001)

Thermal-CVD950 C2H2+NH3

Ni, CoAligned CNT

TSF 398-399 150 (2001)850 C2H2+H2, C2H2+N2 Tangled CNT

Thermal-CVD950 C2H2+NH3

NiAligned CNT

DRM 10 1235 (2001)950 C2H2+H2, C2H2+N2 Tangled CNT

Thermal-CVD

800~900 C2H2+NH3

NiAligned CNT

JAP 91 3847 (2002)600~900 C2H2+H2

Tangled CNT

PE-CVD 660< C2H2+NH3 Ni Aligned CNT APL 80 4018 (2002)

Thermal-CVD 850~900 C2H2+Ar Ni, Co Tangled CNT APL 75 1721 (1999)

PE-CVD 500 CH4+N2 Fe, Ni Aligned CNT APL 75 3105 (1999)

PE-CVD 550 CH4+N2 Fe Aligned CNT JAP 89 5939 (2001)

PE-CVD 700 CH4+H2 Ni Aligned CNT APL 76 2367 (2000)

Thermal-CVD 800 ferrocene+xylene Fe Aligned CNT APL 77 3764 (2000)

But why?

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Ni particles after pretreatment for 1h…

Activated Nitrogen

300nm300nm

300nm300nm

In H2+N2

In pure NH3

Activated Nitrogen plays a significant role in vertically aligned CNT growth

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NH3

NH3

H2

H2

NH3

H2

Pretreatment Reaction

Role of activated nitrogen during CNT growth?

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Pretreatment in NH3 environment was neither a sufficient nor necessary for vertically aligned CNT growth

There are some relationship between nitrogen concentration in CNT and CNT growth rate

Nitrogen is chemically bonded with carbon atoms in graphite basal plane

Enhanced CNT growth in an NH3 environment is due to nitrogen incorporation into the CNT wall or cap.

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Experimental Route (PECVD)


eg: Al, Si, Fe, K)


eg: Al, Si, Fe, K)



Nanocarbon Growth

Nanocarbon Growth

CharacterizationCharacterization







Properties Analysis





Properties Analysis


• Carrier gas (H2, N2, NH3)


• Carrier gas (H2, N2, NH3)

Substrate (CC)

Substrate (CC)

TreatmentTreatmentImpregnationImpregnation

CNFCNF

CNF After TreatmentCNF After Treatment

Polymer (PP)

Polymer (PP)

CNF Reinforced

CNF Reinforced





• Cat. + deionized water + acetone

• under ultrasonic, 30 min, 25oC (water bath)

• aging 12 hr, 60oC

• Cat. + deionized water + acetone

• under ultrasonic, 30 min, 25oC (water bath)

• aging 12 hr, 60oC



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Setup (PECVD)

Schematic Diagram of a PECVD system

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Growth Condition (PECVD)

Process Pretreatment Growth

Sources N2+H2 NH3+C2H4

Parameter (T,t,P,%, etc) Will be determine later

To enhanced the catalytic activity

Vertical align CNF induce by plasma electric field

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CNF Reinforced Composite

Polymer (PP) blending process with CNF.Enhanced the electrical and mechanical properties, light weight

Plastic itself is insulator. Plastic is fragile when expose to high temp, sunlight.Commercial fiber are heavy. CNF will reduce weight and cost efficiency (low fuel) if use in vehicle body part.

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PP

Polypropylene (polypropene) or (C3H6)n

Semi-rigid, good chemical resistance, tough, good fatigue resistance, good heat resistance, non toxicCheapDensity = 0.95 g/cm3

Melting point = 173 oCChosen because PP is a linear polymer that can contribute to the development of highly aligned nanofiber system

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Blending Process

CNFCNF Spinning Process

Spinning Process

• Temp = 285oC• Speed Rotor=

600 rpm• Time = ?min

• Temp = 285oC• Speed Rotor=

600 rpm• Time = ?min

Melt BlendMelt Blend

• Temp = 170-180oC

• Speed Rotor = 30 rpm

• Time = 5-10 min

• Temp = 170-180oC

• Speed Rotor = 30 rpm

• Time = 5-10 min

PolypropylenePolypropylene

CNF Reinforced

CNF Reinforced

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CNF are expected to be produced with below criteria :

Vertically alignStrong attachment onto substrateImproved mechanically & electrically properties

CNF-polymer reinforced composite are expected to be produced with below criteria:

Light weightGood mechanical & electrical properties

Conclusion

objective

Documents

grafting of catalyst

cnf formation

cnf attachment

cnf growthmetallocene

catalyst precursorwhy

cnf characteristic diameter

fe fe ni co13metallocene

catalyst size main important