smart functional nanoenergetic materials graphene as a ......

Smart Functional Nanoenergetic MaterialsSmart Functional Nanoenergetic Materialsgg

Graphene as a Reactive Material and Graphene as a Reactive Material and Carrier of Energetic MaterialsCarrier of Energetic MaterialsCarrier of Energetic MaterialsCarrier of Energetic Materials

I. A. Aksay, A. Selloni, R. Car, I. A. Aksay, A. Selloni, R. Car, C. Zhang, D. M. DabbsC. Zhang, D. M. Dabbs

I. A. Aksay, A. Selloni, R. Car, I. A. Aksay, A. Selloni, R. Car, C. Zhang, D. M. DabbsC. Zhang, D. M. Dabbs. Zhang, D. M. Dabbs. Zhang, D. M. Dabbs

Chemical and Biological Engineering and ChemistryChemical and Biological Engineering and ChemistryPrinceton University, Princeton, NJ 08544 Princeton University, Princeton, NJ 08544

N Kumbhakarna S T Thynell R A YetterN Kumbhakarna S T Thynell R A Yetter

. Zhang, D. M. Dabbs. Zhang, D. M. DabbsChemical and Biological Engineering and ChemistryChemical and Biological Engineering and Chemistry

Princeton University, Princeton, NJ 08544 Princeton University, Princeton, NJ 08544

N Kumbhakarna S T Thynell R A YetterN Kumbhakarna S T Thynell R A YetterN. Kumbhakarna, S. T. Thynell, R. A. YetterN. Kumbhakarna, S. T. Thynell, R. A. YetterMechanical and Nuclear Engineering Mechanical and Nuclear Engineering

PennState University, University Park, PA 16802PennState University, University Park, PA 16802

J J B DeLisio and M R B DeLisio and M R ZachariahZachariah

N. Kumbhakarna, S. T. Thynell, R. A. YetterN. Kumbhakarna, S. T. Thynell, R. A. YetterMechanical and Nuclear Engineering Mechanical and Nuclear Engineering

PennState University, University Park, PA 16802PennState University, University Park, PA 16802

J J B DeLisio and M R B DeLisio and M R ZachariahZachariah

AFOSR/MURI

J. J. B. DeLisio and M.R. B. DeLisio and M.R. ZachariahZachariahMechanical Engineering Mechanical Engineering

University of University of Maryland, College Park, MD 20742Maryland, College Park, MD 20742

J. J. B. DeLisio and M.R. B. DeLisio and M.R. ZachariahZachariahMechanical Engineering Mechanical Engineering

University of University of Maryland, College Park, MD 20742Maryland, College Park, MD 20742

AFOSR/MURIAugust 21, 2013

Splitting of Graphite into Single SheetsSplitting of Graphite into Single SheetsGraphite Oxide by p yStaudenmaier method (1898) – 4 fold volume expansion Thermal expansion (>500 fold) at 1050°C – Boehm (1962)

850 2/ b BE SA ~850 m2/g by BET and >1800 m2/g by methylene blue adsorption in solventsin solventsDisappearance of graphite peaks after oxidation and elimination of all peaks elimination of all peaks after expansion>80% single sheet highly wrinkled functionalized


wrinkled functionalized grapheneM.J. McAllister et al., Chem. Materials (2007)

STM Images of FGS & HOPGSTM Images of FGS & HOPG

K. N. Kudin, B. Ozbas, H.C. Schniepp, R.K. Prud’homme, IAA, R. Car, Nano Lett. 8 (2008)


Functionalized Graphene SheetsFunctionalized Graphene SheetsFGS: functionalized

FGS (C/O=1.85) without vacancy defectFGS: functionalized graphene sheet

Large (>2µm diameter) polycyclic hydrocarbon polycyclic hydrocarbon Commercial production of single sheets (Vorbeck Materials, Jessup, MD)Materials, Jessup, MD)Sheet wrinkling inhibits restacking, maintains surface area FGS (C/O=1.64) with vacancy defect

Unit cell

Lattice defects Oxygen-decorated carbon vacancies Topological defects

Oxygen-containing groupsEpoxides hydroxides


Epoxides, hydroxides, carboxyls

C. Zhang, 2013

Unit cell

Catalyzed NM DecompositionCatalyzed NM DecompositionOxygen-decorated vacancy

J. L. Sanbourin et al., submitted (2013)

Catalytic role of FGS essential to transform nitromethane into more reactive intermediates

Once formed, reactions continue within the fluid Fast decomposition:Fast decomposition:

After ~14 ps, complete transformation into different species Main combustion products are H2O, CO2, and N2

Protonation, deprotonation and oxidation reactions promoted by


, p p yoxygen groups on FGS at carbon vacancies

Tetrazine DecompositionTetrazine DecompositionA. Bhattacharya, J. Chem. Phys. 2009

N≡N + 2RCN

• Low C, H content • Good oxygen balance yg• N-N increases heat of formation• N≡N produced • N-O enhances aromaticity, reduces

iti it N≡N +


sensitivity N N

Energetic ScaffoldingEnergetic ScaffoldingCh mi l m difi ti n Chemical modification of FGSs

Planar and edge chemistries for attaching dispersants or binders Joining of FGSs for

FGS

porous structuresSpacers

Long chain bridging Tetrazine bridge

Long chain bridging molecules In collaboration with ENS Cachan (France)ENS Cachan (France)

FGS

Fabien Miomandre and Pierre Audebert, École Normale Supérieure de Cachan, France


FGS

Synthesis of Modified TetrazinesSynthesis of Modified TetrazinesFabien Miomandre and Pierre Audebert, É l N m l S pé i d C h n F n

A

École Normale Supérieure de Cachan, France

B

Dichloro-s-tetrazine (TzCl2)

NN

C

NN N

N

Cl

NNCl O

HOOH

ON N

NNCl

+CH2Cl2

2,4,6-collidine


Cl N NCl O

D

Pure tetrazinesTetrazines and TzTetrazines and Tz--FGSFGS

Tetrazines attached to FGS (Tz-FGS)

JL25: JL4 attached to FGSJL4 C

JL24: JL40 attached to FGSBJL40

JL43: JL41 attached to FGSJL41 JL43: JL41 attached to FGSJL41

JL38: JL37 bridging 2 FGSsJL37 D


• π bond: resonance ff d i

A

Tetrazine ElectrochemistryTetrazine Electrochemistry

6 0 10-7

Cl-Tz-Cl

effect, e- donating

• σ bond: inductive effect, e- withdrawing

For TzCl inductive effect is much stronger

3,0x10-7

6,0x10 7 Cl Tz Cl Cl-Tz-O-(CH2)4-O-Tz-Cl Adam-CH2-O-Tz-Cl CH3-(CH2)3-O-Tz-Cl

For TzCl2, inductive effect is much stronger than the resonance effect, making tetrazine ring electron deficient and redox peaks more positive

cathodic

-3,0x10-7

0,0

C

urre

nt A B

C

-6,0x10-7

,C

Danodic

-1,5 -1,0 -0,5 0,0 0,5 1,0 1,5-9,0x10-7

Potential V

D

Inductive effect from electron-donating


ggroups: tetrazine ring becomes electron rich compared to ring in TzCl2

A

Dichlorotetrazine and FGSDichlorotetrazine and FGSA

×

2,0x10-7

FGS2

TzClTzCl2 does not bind t FGS

1,0x10-7

,

A

TzCl2 Cl-Tz-O-Graphene

to FGSConfirmed by FTIR and thermal analysisT Cl t ith

-1,0x10-7

0,0 C

urre

nt TzCl2 can react with

solvent, catalyst Ab-initio model shows TzCl2 physisorption

1 5 1 0 0 5 0 0 0 5 1 0 1 5

-2,0x10-7

, TzCl2 physisorption on FGS energetically favored over chemisorption


-1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 Potential V

Tetrazines Bound to FGSTetrazines Bound to FGSB C

1,0x10-6

1,5x10-6

FGS2

Adam-CH2-O-Tz-ClAdam-CH -O-Tz-O-Graphene2,0x10-6

3,0x10-6

FSG2

CH3-(CH2)3-O-Tz-Cl Graphene-O-Tz-O-(CH2)3-CH3

7

0,0

5,0x10-7

C

urre

nt A

Adam CH2 O Tz O Graphene

1 0x10-6

0,0

1,0x10-6

2,0x10

C

urre

nt A

2 3 3

1 5 1 0 0 5 0 0 0 5 1 0 1 5-1,5x10-6

-1,0x10-6

-5,0x10-7

1 5 1 0 0 5 0 0 0 5 1 0 1 5

-3,0x10-6

-2,0x10-6

-1,0x10

-1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 Potential V

-1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 Potential V

Binding visible as shift in redox peaks for FGS and tetrazineRedox peaks of tetrazines shift to negative after grafting (FGS acts as e- donating group)


p f f g f g f g ( g g p)Redox peaks of FGSs shift to positive after grafting (tetrazine acts as e- withdrawing group)

Infrared Spectra of Pure TetrazinesInfrared Spectra of Pure TetrazinesC-H stretch

JL 40 BC-N stretchJL 40A

bs

B

JL 41

Abs

JL 4

Abs C

DJL 37

Abs

1000 1500 2000 2500 3000 3500

Wavenumbers (cm-1)

Strong C-N (aromatic) stretch between 1400-1500 cm-1

C H h f b i (2800 3000 1)


C-H stretch from substituent groups (2800-3000 cm-1)Ether bridge between substituent and tetrazine ring ~1200 cm-1

FGSs Bridged by TetrazineFGSs Bridged by Tetrazine

D

3,0x10-6 FGS2

Cl Tz O (CH ) O Tz Cl

Redox peaks of JL 37, FGS shift as with other

0 0

1,0x10-6

2,0x10-6 Cl-Tz-O-(CH2)4-O-Tz-Cl Graphene-O-Tz-O-(CH2)4-O-Tz-O-Graphene

A

FGS shift as with other Tz-FGS productsShifts in redox peaks roughly equivalent for all

-2,0x10-6

-1,0x10-6

0,0

C

urre

nt A

yTz-FGS products, regardless of type of tetrazine grafted onto FGS

-1,5 -1,0 -0,5 0,0 0,5 1,0 1,5-4,0x10-6

-3,0x10-6

FGSIndicates similar bonding behavior (e.g., proximity of tetrazine ring to FGS through bridging ether)


Potential Vg g )

Infrared of Tetrazines on FGSInfrared of Tetrazines on FGSC N B

C=O on FGSC-N

stretch BJL 24 A

bs

JL 43Abs

C-H stretch C

JL 25Abs

DJL 38Abs

1000 1500 2000 2500 3000 3500 Wavenumbers (cm-1)

Tetrazine association with FGS indicated by C-H (2800-2950 cm-1) and C-N (~1600 cm-1) stretching frequencies not seen on native FGS


Ether bridge masked by multiple absorption bands in 1000-1300 cm-1 regionC-H and C-N bands disappear after heating Tz-FGS to high temperature (>400°C)

Optimized Structures for FGS2 and Dichloro-s-TetrazineModeling Tetrazine Binding to FGSModeling Tetrazine Binding to FGS

Optimized Structures for FGS2 and Dichloro s Tetrazine

dOH-N = 1.77 ÅdOH-N = 1.77 ÅdOH-C = 2.44 ÅdOH-C = 2.44 Å

FGS mixed with TzClFGS mixed with TzCl

TzCl2 covalently bound to FGS2TzCl2 covalently bound to FGS2

FGS2 mixed with TzCl2FGS2 mixed with TzCl2

vibrational mode corresponding to 3047 cm-1


vibrational mode corresponding to 3047 cm 1

Unit cell 7.77 × 8.78 × 30 Å3; Cubic cell 30 × 30 × 30 Å3 with MP correction

Energy Energy Difference: Difference: Products and Products and ReactantsReactants

E (Ry) - PBE E (Ry) - PBE-vdW E (eV) - vdW

Dichloride-Tz (~6 Å) -162.1805122731 -162.186631801034 -0.049( )

FGS2 -697.9309461955 -698.110388095506 -2.500

FGS2 - dichloride-Tz (physi) -860.1229108453 -860.330779074904 -2.865

FGS2 - dichloride-Tz (chemi) -828.8369113821 -829.051351415406 -2.975

HCl -31.2146620615 -31.216230021156 0.000

FGS2 + dichloro-Tz FGS2 - dichloro-Tz (physisorbed)

ΔEPBE = -0.156 eV , ΔEPBE-vdW = -0.459 eV

FGS2 - dichloro-Tz (physi) FGS2 – 1-oxy, 4-chloro-Tz (chemisorbed) + HClΔEPBE = 0.966 eV , ΔEPBE-vdW = +0.860 eV


Covalent bond energetically unfavorable!

Optimized Structures for JL40 and JL24Optimized Structures for JL40 and JL24

B

JL40 JL24

B

dOH-N = 1.72 ÅdOH-C = 2.83 ÅdOH-N = 1.72 ÅdOH-C = 2.83 Å

Butoxy-Tz (JL40) covalently bound to FGS2Butoxy-Tz (JL40) covalently bound to FGS2FGS2 mixed with butoxy-Tz (JL40)FGS2 mixed with butoxy-Tz (JL40) Vibrational mode corresponding to 2969 cm-1


Energy Energy Difference: Difference: Products and Reactants Products and Reactants Unit cell 7.77 × 8.78 × 40 Å3; Cubic cell 30 × 30 × 30 Å3 with MP correction

E (Ry) - PBE E (Ry) - PBE-vdW E (eV) - vdW

butoxy-Tz (~10 Å) -220.4648826439 -220.478220728922 -0.193y ( )

FGS2 -697.9309345403 -698.110388095506 -2.500

FGS2 - butoxy-Tz (physi) -918.4079033041 -918.621008247310 -2.9722 y (p y )

FGS2 - butoxy-Tz (chemi) -887.1673536470 -887.427812619112 -3.639

HCl -31.2146620615 -31.216230021156 0.000

FGS2 + Butoxy-Tz FGS2 - butane-Tz (physi)ΔEPBE = -0.164 eV , ΔEPBE-vdW = -0.441 eV

FGS2 - Butoxy-Tz (physi) FGS2 – 1-oxo, 4-butoxy-Tz (chemi) + HClΔEPBE = 0.352 eV , ΔEPBE-vdW = -0.313 eV


20

Covalent bond energetically favorable!

Dichlorotetrazine and JL 40 Dichlorotetrazine and JL 40 Under N2

TGA

DSC Hea

Vaporization

Dichlorotetrazine mas

s (%

)at lost or ga

BM l

Dichlorotetrazine

Chan

ge in

ained (mW

/m

JL40Melting

Sublimation

mg)

Under slow thermal ramp (10°C/min) dichlorotetrazine sublimes but JL 40 meltsJL 40 vaporizes and does not decompose under experimental heating conditions

Temperature (°C)


JL 40 vaporizes and does not decompose under experimental heating conditions

JL 40 and JL 24JL 40 and JL 24Under N2

TGA

DSC Hea

JL24: JL40 on FGSVaporization

mas

s (%

)at lost or ga

BJL40

Chan

ge in

ained (mW

/m

Melting

mg)

Low molecular weight substituent sufficient to yield stable liquid phaseSlow thermal ramp shows only desorption of tetrazine when associated with FGS

Temperature (°C)


Slow thermal ramp shows only desorption of tetrazine when associated with FGS

In t nd d th m l

Energetics of Tetrazines Energetics of Tetrazines and Tzand Tz--FGSFGSIn standard thermal analysis, condense phase may vaporize during slow thermal ramp Confined Rapid Thermolysis (CRT)/FTIRThermolysis (CRT)/FTIR

Rapid heating rate 2000K/s to 1,000psig 50H li 50Hz sampling 2cm-1 resolution Sample allowed to decompose under isothermal conditions Very sensitive to decomposition occurring in S. Thynell


condensed phases

Enhanced Decomposition of Tetrazines on FGSEnhanced Decomposition of Tetrazines on FGS

Tz

Tz-FGS

Tz

S. Thynell

Tz

Evolved gas analysis during CRT shows JL 37 and JL 40 decompose at 335°C Decomposition of tetrazine (JL 37) is more extensive when bound to FGS (JL 38)

no tetrazine vapor apparent higher amounts of decomposition products formed

y


no tetrazine vapor apparent, higher amounts of decomposition products formed In comparison, dichlorotetrazine goes into vapor phase with no decomposition

TT--Jump TimeJump Time--ofof--Flight Mass SpecFlight Mass Spec0 003” diameter Pt wire is 0.003 diameter Pt wire is coated with sample of interest.Wire is rapidly heated at p y105 K/s within the extraction region of a linear TOF mass spectrometerspectrometer.Time resolved spectra are acquired during a single reaction event.Electrical characteristics of the wire are monitored to determine wire temperature at any given time during at any given time during heating.A data sampling rate of 10 kHz was used.


kHz was used.L. Zhou, et al., M.R. Zachariah, Rap. Commun. Mass Spec. (2009)

JL 37 and JL 38JL 37 and JL 38

Decomposition of pure tetrazine (JL 37) is delayed when attached to FGS (JL 38) Significant decomposition of JL 37 at 0.6 ms (597 K), delayed to 1.4 ms on FGS (840 K)


Significant decomposition of JL 37 at 0.6 ms (597 K), delayed to 1.4 ms on FGS (840 K)

No large mass fragments in JL 38: more complete decomposition of tetrazine

Dielectric Dielectric ElastomersElastomers with Stiff Electrodeswith Stiff Electrodes

Voltage as a function of stretch Voltage as a function of stretch ((electrodes: 3 wt. % electrodes: 3 wt. % FGS22FGS22--SE; SE;

elastomerelastomer: VHB, H2/H1=0.2): VHB, H2/H1=0.2)

1

5'=λ3

2


5=λ

Adaptive Materials (Adaptive Materials (NanocompositesNanocomposites))


Z. Fang, et al., IAA Appl. Opt. 49 (2010)

SummarySummaryDeveloped synthesis methods to construct Developed synthesis methods to construct nanocomposite fuels using functionalized graphene sheets as (i) nucleation templates and stabilizer for energetic particles, polymeric nitrogen molecules, embedded nitrogen; and embedded nitrogen; and (ii) carbocatalysts Covalent attachment of tetrazines is confirmed b F h l l d by CV, FTIR, thermal analysis, and quantum mechanical modeling to understand the fundamental mechanisms of energetic functions. fundamental mechanisms of energetic functions. High surface area, hierarchically structured graphene-tetrazine networks will be developed f ll d l


for controlled energy release.

smart functional nanoenergetic materials graphene as a ......

Documents