1. M. Arjmand a, L. Laurentius b , U. Sundararaj a
Nitrogen-Doped Carbon Nanotube / Polymer Nanocomposites: Versatile Materials for Charge Storage
M. Arjmand a, L. Laurentius b , U. Sundararaj a
a Department of Chemical and Petroleum Engineering, University of Calgary
b Department of Chemistry, National Institute for Nanotechnology, University of Alberta
CSChE 2015

2. CHRONOLOGICAL DEVELOPMENT OF CAPACITORS
Conventional Capacitors like Ceramic Capacitors
High-k Ceramic Powder / Polymer Capacitors
Conductive Filler / Polymer Capacitors (CPCs)

3. WHAT MAKES A CPC UNIQUE FOR CHARGE STORAGE?
Nano-Capacitor: Conductive Filler as Nanoelectrode and Polymer Matrix as Nanodielectric

4. DIELECTRIC RESPONSE TO APPLIED ELECTRIC FIELD
Interfacial
Log (ε′)
X-Band ( GHz) 3 8 12 15
Log (Frequency (Hz))

5. Polarization Mechanisms Over the X-Band (8.2-12.4 GHz)
Interfacial ×
Dipolar (PVDF Matrix) ×
CNT Polarization Yes
Electronic Polarization Yes

6. Unrolled Undoped and Nitrogen Doped Carbon Nanotube Under Electric Field

7. Chemical Vapor Deposition (CVD) Setup

8. X-ray Photoelectron Spectroscopy

9. Transmission Electron Microscopy
Nitrogen-Doped CNTs
Undoped CNTs

10. Raman Spectroscopy Sample # ID/IG IGʹ/IG N-doped Nanocomposites 0.82
0.21
Undoped Nanocomposites
0.66
0.94

11. Length and Diameter

12. Percolation Curve

13. Dielectric Permittivity and Loss

14. Conceptualization of Imaginary Permittivity+ + +

15. Real Permittivity
The electric dipole has a magnitude equals the strength of each charge times the separation distance between charges.
Real permittivity represents the magnitude and quantity of dipoles.

16. Dissipation Factor Sample # Real Permittivity Dielectric Loss
N-doped Nanocomposites 9
1.96
Undoped Nanocomposites
6.21

17. Conclusions
Nitrogen doping deteriorated the crystallinity and metallicity of carbon nanotubes.
The positive impact of nitrogen doping on lowering the dielectric loss overshadowed it negative impact on reducing dielectric permittivity.
Nitrogen doping can be used as an efficient technique to tune the dielectric properties of carbon nanotube/polymer nanocomposites.

18. Acknowledgements
Natural Sciences and Engineering Research Council (NSERC) of Canada
Dr. Kambiz Chizari and Mr. Abdalla for their assistance with carbon nanotube synthesis and nanocomposite preparation.

19. Thanks For Your Attention !

20. Back-Up Slides

21. Parameters Affecting Electrical Properties of N-CNT/Polymer Nanocomposite
Synthesis Yield (TGA)
Length and Diameter (TEM)
Crystallinity (Raman Spectroscopy)
Metallicity (Raman Spectroscopy and STS)
Nitrogen Content and Bonding Type (XPS)

22. Light Microscopy

23. Relative Transparency

24. N-CNT Growth Mechanism (Cont’d)
Reyes-Reyes M, Grobert N, Kamalakaran R, Seeger T, Golberg D, Ruhle M, et al.. Chem Phys Lett 2004;396(1-3):

25. N-CNT Growth Mechanism
Bamboo-Shaped
Fe Catalyst
Open-Channel
Co Catalysts
van Dommele S, Romero-Izquirdo A, Brydson R, de Jong KP, Bitter JH. Carbon 2008;46(1):
Hofmann S, Sharma R, Ducati C, Du G, Mattevi C, Cepek C, et al. Nano Lett 2007;7(3):602-8.

26. What Makes CPC Different For Use As Charge Storage Material?
The electric dipole has a magnitude equals to the strength of each charge times the separation between charges.
Interfacial Polarization + + + + - + + + + +
Electronic Polarization

27. Embedded Capacitor
In a typical microelectronic product, around 80% of the electronic components are passive components, such as capacitors, which take up more than 40% of the printed circuit board (PCB) surface area.1 2
1 J. X. Lu, K. S. Moon, J. W. Xu, and C. P. Wong, J. Mater. Chem. 16 (16), 1543 (2006). 2

28. What Makes Doping Important for Electronic Properties?
Isolator-Metal. Available from:

29. Different Types of Nitrogen Bonding in Graphitic Structures
Wei DC, Liu YQ, Wang Y, Zhang HL, Huang LP, Yu G. Nano Lett 2009;9(5):

30. Nitrogen-doped (N-CNT) Synthesis Procedure
Incipient wetness impregnation of catalyst precursors (Metal Nitrate and Sulfate Components) onto Alumina Support
Drying (25ºC) - Calcination with air at 350ºC – Reduction with Hydrogen at 400ºC
Synthesis at 750ºC for 2h – Precursor Gases (Ethane and Ammonia) - Carrier Gas (Hydrogen)

31. X-ray Photoelectron Spectroscopy

32. Doping of Carbon Nanotubes: Why Nitrogen and Boron?

33. TGA Analysis Sample # Inflection Point (ºC) N-doped Nanocomposites 517
Undoped Nanocomposites
650

34. Challenges in Manipulating CPCs as Charge Storage Materials
High real permittivity is achievable close to or above percolation threshold.1
The insulator–conductor transition, which occurs at percolation threshold, precludes CPCs being used above the percolation threshold.
There is a typically narrow insulator-conductor transition window to regulate dielectric properties.
1Dang ZM, Yao SH, Yuan JK, and Bai JB. J Phys Chem C 2010; 114: