Nitrogen doped carbon, synthesized by a novel way of carbonizing polyaniline in an inert atmosphere at a constant temperature of , exhibits several unique features. The carbon: nitrogen ratio is found to increase with the treatment duration up to 120 minutes and a mass reduction of 60 wt% is observed with an interesting observation of the retention of the bulk polymer morphology, surprisingly, even after the carbonization process. The electrochemical activity evaluated with potassium hexacyanoferrate and hexamine ruthenium redox systems at a regular time interval helps to tune the catalytic activity. This type of nitrogen doped carbon prepared from polyaniline base exhibits excellent electrocatalytic activity as illustrated by the oxidation of ascorbic acid in neutral medium. 1. Introduction Carbon is one of the prospective candidates in the field of electroanalysis mainly because of its broad potential window, very little background current, rich surface chemistry, chemical stability, and most importantly abundance [1]. A range of active carbon materials demonstrates requisite characteristics of a good catalyst support; however, they generally exhibit poor inherent catalytic activity for many technologically relevant reactions [2]. Previously, several methods have been used to alter the carbon support in an effort to improve its electrochemical reactivity. In addition to optimization of morphological properties, chemical modification of the carbon surface has been explored in order to enhance or tune the electrochemical activity of the carbon materials. Introduction of heteroatom such as oxygen, nitrogen, boron, sulfur, and halogen into the carbon matrix plays an important role in improving the catalytic performance [3]. For example, boron doping in carbon materials significantly improves the electrical conductivity and it is influenced by the boron doping level [4]. Sulfur doped amorphous carbon has been used as anode material for lithium ion batteries [5]. The added sulfur favorably increases the charge capacity and improves the electrochemical properties of the anode. However, the incorporated sulfur heteroatoms produce some side effects when they exist in unfavourable states. Among the heteroatom’s investigated, nitrogen doped carbon (NDC) has received significant attention as competitive oxygen reduction electrocatalysts. It is because nitrogen atom can donate the lone pair of electron to the carbon substrates more easily, which undergoes delocalization within the carbon material. Therefore, the adsorption properties as well as the electron
References
[1]
R. L. McCreery, “Advanced carbon electrode materials for molecular electrochemistry,” Chemical Reviews, vol. 108, no. 7, pp. 2646–2687, 2008.
[2]
D. R. Rolison, “Catalytic nanoarchitectures—the importance of nothing and the unimportance of periodicity,” Science, vol. 299, no. 5613, pp. 1698–1701, 2003.
[3]
F. Li, Q. Qian, F. Yan, and G. Yuan, “Nitrogen-doped porous carbon microspherules as supports for preparing monodisperse nickel nanoparticles,” Carbon, vol. 44, no. 1, pp. 128–132, 2006.
[4]
M. Endo, C. Kim, T. Karaki et al., “Anode performance of a Li ion battery based on graphitized and B-doped milled mesophase pitch-based carbon fibers,” Carbon, vol. 37, no. 4, pp. 561–568, 1999.
[5]
Y. P. Wu, S. Fang, Y. Jiang, and R. Holze, “Effects of doped sulfur on electrochemical performance of carbon anode,” Journal of Power Sources, vol. 108, no. 1-2, pp. 245–249, 2002.
[6]
Y. Shao, J. Sui, G. Yin, and Y. Gao, “Nitrogen-doped carbon nanostructures and their composites as catalytic materials for proton exchange membrane fuel cell,” Applied Catalysis B, vol. 79, no. 1, pp. 89–99, 2008.
[7]
P. H. Matter, E. Wang, and U. S. Ozkan, “Preparation of nanostructured nitrogen-containing carbon catalysts for the oxygen reduction reaction from SiO2- and MgO-supported metal particles,” Journal of Catalysis, vol. 243, no. 2, pp. 395–403, 2006.
[8]
D. Deng, X. Pan, L. Yu et al., “Toward N-doped graphene via solvothermal synthesis,” Chemistry of Materials, vol. 23, no. 5, pp. 1188–1193, 2011.
[9]
S. Yang, X. Feng, X. Wang, and K. Müllen, “Graphene-based carbon nitride nanosheets as efficient metal-free electrocatalysts for oxygen reduction reactions,” Angewandte Chemie International Edition, vol. 50, no. 23, pp. 5339–5343, 2011.
[10]
S. Ma, G. A. Goenaga, A. V. Call, and D.-J. Liu, “Cobalt imidazolate framework as precursor for oxygen reduction reaction electrocatalysts,” Chemistry: A European Journal, vol. 17, no. 7, pp. 2063–2067, 2011.
[11]
D. Geng, Y. Chen, Y. Chen et al., “High oxygen-reduction activity and durability of nitrogen-doped graphene,” Energy and Environmental Science, vol. 4, no. 3, pp. 760–764, 2011.
[12]
Y. Xia and R. Mokaya, “Generalized and facile synthesis approach to N-doped highly graphitic mesoporous carbon materials,” Chemistry of Materials, vol. 17, no. 6, pp. 1553–1560, 2005.
[13]
A. B. Fuertes and T. A. Centeno, “Mesoporous carbons with graphitic structures fabricated by using porous silica materials as templates and iron-impregnated polypyrrole as precursor,” Journal of Materials Chemistry, vol. 15, no. 10, pp. 1079–1083, 2005.
[14]
C.-M. Yang, C. Weidenthaler, B. Spliethoff, M. Mayanna, and F. Schüth, “Facile template synthesis of ordered mesoporous carbon with polypyrrole as carbon precursor,” Chemistry of Materials, vol. 17, no. 2, pp. 355–358, 2005.
[15]
A. Lu, A. Kiefer, W. Schmidt, and F. Schüth, “Synthesis of polyacrylonitrile-based ordered mesoporous carbon with tunable pore structures,” Chemistry of Materials, vol. 16, no. 1, pp. 100–103, 2004.
[16]
M. Kruk, K. M. Kohlhaas, B. Dufour et al., “Partially graphitic, high-surface-area mesoporous carbons from polyacrylonitrile templated by ordered and disordered mesoporous silicas,” Microporous and Mesoporous Materials, vol. 102, no. 1–3, pp. 178–187, 2007.
[17]
W. Li, D. Chen, Z. Li et al., “Nitrogen-containing carbon spheres with very large uniform mesopores: the superior electrode materials for EDLC in organic electrolyte,” Carbon, vol. 45, no. 9, pp. 1757–1763, 2007.
[18]
C. Jeyabharathi, P. Venkateshkumar, M. S. Rao, J. Mathiyarasu, and K. L. N. Phani, “Nitrogen-doped carbon black as methanol tolerant electrocatalyst for oxygen reduction reaction in direct methanol fuel cells,” Electrochimica Acta, vol. 74, pp. 171–175, 2012.
[19]
L. Li, E. Liu, J. Li et al., “A doped activated carbon prepared from polyaniline for high performance supercapacitors,” Journal of Power Sources, vol. 195, no. 5, pp. 1516–1521, 2010.
[20]
Z. Lei, M. Zhao, L. Dang et al., “Structural evolution and electrocatalytic application of nitrogen-doped carbon shells synthesized by pyrolysis of near-monodisperse polyaniline nanospheres,” Journal of Materials Chemistry, vol. 19, no. 33, pp. 5985–5995, 2009.
[21]
M. Trchová, E. N. Konyushenko, J. Stejskal, J. Ková?ová, and G. ?iri?-Marjanovi?, “The conversion of polyaniline nanotubes to nitrogen-containing carbon nanotubes and their comparison with multi-walled carbon nanotubes,” Polymer Degradation and Stability, vol. 94, no. 6, pp. 929–938, 2009.
[22]
J. Stejskal and R. G. Gilbert, “Polyaniline. Preparation of a conducting polymer (IUPAC technical report),” Pure and Applied Chemistry, vol. 74, no. 5, pp. 857–867, 2002.
[23]
B. Sreedhar, P. Radhika, B. Neelima, N. Hebalkar, and M. V. B. Rao, “Synthesis and characterization of polyaniline: nanospheres, nanorods, and nanotubes—catalytic application for sulfoxidation reactions,” Polymers for Advanced Technologies, vol. 20, no. 12, pp. 950–958, 2009.
[24]
M. Trchová, P. Matějka, J. Brodinová, A. Kalendová, J. Proke?, and J. Stejskal, “Structural and conductivity changes during the pyrolysis of polyaniline base,” Polymer Degradation and Stability, vol. 91, no. 1, pp. 114–121, 2006.
[25]
J. Stejskal, M. Trchová, and I. Sapurina, “Flame-retardant effect of polyaniline coating deposited on cellulose fibers,” Journal of Applied Polymer Science, vol. 98, no. 6, pp. 2347–2354, 2005.
[26]
J. Stejskal, M. Trchová, J. Brodinová, and I. Sapurina, “Flame retardancy afforded by polyaniline deposited on wood,” Journal of Applied Polymer Science, vol. 103, no. 1, pp. 24–30, 2007.
[27]
X. Zhang and S. K. Manohar, “Microwave synthesis of nanocarbons from conducting polymers,” Chemical Communications, no. 23, pp. 2477–2479, 2006.
[28]
Z. Rozlívková, M. Trchová, M. Exnerová, and J. Stejskal, “The carbonization of granular polyaniline to produce nitrogen-containing carbon,” Synthetic Metals, vol. 161, no. 11-12, pp. 1122–1129, 2011.
[29]
J. Stejskal, M. Trchová, J. Hromádková, J. Ková?ová, and A. Kalendová, “The carbonization of colloidal polyaniline nanoparticles to nitrogen-containing carbon analogues,” Polymer International, vol. 59, no. 7, pp. 875–878, 2010.
[30]
J. Cao, J.-Z. Sun, J. Hong, H.-Y. Li, H.-Z. Chen, and M. Wang, “Carbon nanotube/CdS core-shell nanowires prepared by a simple room-temperature chemical reduction method,” Advanced Materials, vol. 16, no. 1, pp. 84–87, 2004.
[31]
M. I. Boyer, S. Quillard, G. Louarn, G. Froyer, and S. Lefrant, “Vibrational study of the FeCl3-doped dimer of polyaniline; a good model compound of emeraldine salt,” Journal of Physical Chemistry B, vol. 104, no. 38, pp. 8952–8961, 2000.
[32]
M. Cochet, G. Louarn, S. Quillard, J. P. Buisson, and S. Lefrant, “Theoretical and experimental vibrational study of emeraldine in salt form part II,” Journal of Raman Spectroscopy, vol. 31, no. 12,, pp. 1041–1049, 2000.
[33]
S. Y. Chee and M. Pumera, “Metal-based impurities in graphenes: application for electroanalysis,” Analyst, vol. 137, no. 9, pp. 2039–2041, 2012.
[34]
G. Socrate, Infrared and Raman Characteristic Group Frequencies, Wiley, 2001.
[35]
L. Niu, Q. Li, F. Wei, X. Chen, and H. Wang, “Electrochemical impedance and morphological characterization of platinum-modified polyaniline film electrodes and their electrocatalytic activity for methanol oxidation,” Journal of Electroanalytical Chemistry, vol. 544, pp. 121–128, 2003.
[36]
G. Wu and B.-Q. Xu, “Carbon nanotube supported Pt electrodes for methanol oxidation: a comparison between multi- and single-walled carbon nanotubes,” Journal of Power Sources, vol. 174, no. 1, pp. 148–158, 2007.
[37]
K. S. Ngai, W. T. Tan, Z. Zainal, R. B. M. Zawawi, and M. Zidan, “Electrochemical oxidation of ascorbic acid mediated by single-walled carbon nanotube/tungsten oxide nanoparticles modified glassy carbon electrode,” International Journal of Electrochemical Science, vol. 7, no. 5, pp. 4210–4222, 2012.
[38]
J. B. Raoof, R. Ojani, H. Beitollahi, and R. Hossienzadeh, “Electrocatalytic determination of ascorbic acid at the surface of 2,7-bis(ferrocenyl ethyl)fluoren-9-one modified carbon paste electrode,” Electroanalysis, vol. 18, no. 12, pp. 1193–1201, 2006.
[39]
S. A. Wring, J. P. Hart, and B. J. Birch, “Voltammetric behaviour of ascorbic acid at a graphite-epoxy composite electrode chemically modified with cobalt phthalocyanine and its amperometric determination in multivitamin preparations,” Analytica Chimica Acta, vol. 229, no. 1, pp. 63–70, 1990.