One-Pot Facile Synthesis of N-Doped Graphene Synthesized from Paraphenylenediamine as Metal-Free Catalysts for the Oxygen Reduction Used for Alkaline Fuel Cells
 A. Zhao, J. Masa, M. Muhler, W. Schuhmann, and W. Xia, “N-doped carbon synthesized from N-containing polymers as metal-free catalysts for the oxygen reduction under alkaline conditions”, Electrochimica Acta, vol. 98, pp. 139-145, 2013.
 C. Zhang, R. Hao, H. Liao, and Y. Houn, “Synthesis of amino-functionalized graphene as metal-free catalyst and exploration of the roles of various nitrogen states in oxygen reduction reaction”, Nano Energy, vol. 2, pp. 88–97, 2013.
 R. Liu, D. Wu, X. Feng, and K. Mullen, “Nitrogen-Doped Ordered Mesoporous Graphitic Arrays with High Electrocatalytic Activity for Oxygen Reduction”, Angewandte Chemie International Edition, vol. 49, pp. 2565-2569, 2010.
 Y. Li, Y. Zhao, H. Cheng, Y. Hu, G. Shi, L. Dai, and L. Qu, “Nitrogen-doped graphene quantum dots with oxygen-rich functional groups”, Journal of the American Chemical Society, vol. 134, pp. 15–18, 2011.
 S. Wang, D. Yu, L. Dai, D.W. Chang, and J. B. Baek, “Polyelectrolyte-Functionalized Graphene as Metal-Free Electrocatalysts for Oxygen Reduction”, ACS Nano, vol.5, pp. 6202-6209, 2011.
 B. Luo, S. Liu, and L. Zhi, “Chemical Approaches toward Graphene-Based Nanomaterials and their Applications in Energy-Related Areas”, Small, vol. 8, pp. 630–646, 2012.
 L. Lai, J.R. Potts, D. Zhan, L. Wang, C.K. Poh, C. Tang, H. Gong, Z. Shen, J. Lin, and R.S. Ruoff, “Exploration of the active center structure of nitrogen-doped graphene-based catalysts for oxygen reduction reaction”, Energy & Environmental Science, vol. 5, pp. 7936–7942, 2012.
 H. Wang, X. Bo, and C. Luhana, “Nitrogen doped large mesoporous carbon for oxygen reduction electrocatalyst using DNA as carbon and nitrogen precursor”, Electrochem Commun, vol. 5, pp. 5-8, 2012.
 W. Xiao, D. Wang, and XW. Lou, “Shape-Controlled Synthesis of MnO2 Nanostructures with Enhanced Electrocatalytic Activity for Oxygen Reduction”, J Phys Chem C, vol. 114, pp. 1694-1700, 2009.
 M. Lefe, JP. Dodelet, and P. Bertrand, “Molecular Oxygen Reduction in PEM Fuel Cells: Evidence for the Simultaneous Presence of Two Active Sites in Fe-Based Catalysts”, J Phys Chem B, vol. 106, pp. 8705-8713, 2002.
 G. Ma, R. Jia, and J. Zhao, “Nitrogen-Doped Hollow Carbon Nanoparticles with Excellent Oxygen Reduction Performances and Their Electrocatalytic Kinetics”, J Phys Chem C, vol. 115, pp. 25148-25154, 2011.
 B. Zheng, J. Wang, and FB. Wang, “Synthesis of nitrogen doped graphene with high electrocatalytic activity toward oxygen reduction reaction”, Electrochem Commun, vol. 28, pp. 24-26, 2013.
 Z. Yang, Z. Yao, and GF. Li, “Sulfur-Doped Graphene as an Efficient Metal-free Cathode Catalyst for Oxygen Reduction”, ACS Nano, vol. 6, pp. 205-211, 2011.
 ZH. Sheng, HL. Gao, and WJ. Bao, “Facile, scalable synthesis of edge-halogenated graphene nanoplatelets as efficient metal-free eletrocatalysts for oxygen reduction reaction”, Sci Rep, vol.3, pp.1810-1817, 2013.
 B. Wang, “Recent development of non-platinum catalysts for oxygen reduction reaction”, Journal of Power Sources, vol.152, pp.1-318, 2005.
 R. Bashyam, P. Zelenay, “A class of non-precious metal composite catalysts for fuel cells”, Nature, vol.443, pp.63-66, 2006.
 M. Lefèvre, E. Proietti, F. Jaouen, J.-P. Dodelet, “Iron-based catalysts with improved oxygen reduction activity in polymer electrolyte fuel cells”, Science, vol.324, pp.71-74, 2009.
 M. Park, T. Lee, and B. S. Kim, “Covalent functionalization based heteroatom doped graphene nanosheet as a metal-free electrocatalyst for oxygen reduction reaction”, Nanoscale, vol.5, pp. 12255-12260, 2013.
 L. Qu, Y. Liu, J.-B. Baek and L. Dai, “Nitrogen-doped graphene as efficient metal-free electrocatalyst for oxygen reduction in fuel cells”, ACS Nano, vol.4, pp. 1321-1326, 2010.
 D. Yu, L. Wei, W. Jiang, H. Wang, B. Sun, Q. Zhang, K. Goh, R. Si and Y. Chen, “Nitrogen doped holey graphene as an efficient metal-free multifunctional electrochemical catalyst for hydrazine oxidation and oxygen reduction”, Nanoscale, vol.5, pp. 3457-3464, 2013.
 S. Yang, X. Feng, X. Wang and K. Mullen, “Graphene-Based Carbon Nitride Nanosheets as Efficient Metal-Free Electrocatalysts for Oxygen Reduction Reactions”, Angew. Chem., Int. Ed, vol.50, pp. 5339-5343, 2011.
 S. Yang, L. Zhi, K. Tang, X. Feng, J. Maier and K. Mullen, “Efficient Synthesis of Heteroatom (N or S)-Doped Graphene Based on Ultrathin Graphene Oxide-Porous Silica Sheets for Oxygen Reduction Reactions”, Adv. Funct. Mater, vol.22, pp.3634-3640, 2012.
 Z.-W. Liu, F. Peng, H.-J. Wang, H. Yu, W.-X. Zheng and J. Yang, “Carbon Catalysis Phosphorus-Doped Graphite Layers with High Electrocatalytic Activity for the O2 Reduction in an Alkaline Medium”, Angew. Chem., Int. Ed, vol.50, pp.3257-3261, 2011.
 H. Kim, K. Park, J. Hong, and K. Kang, “All-graphene-battery: bridging the gap between supercapacitors and lithium ion batteries”, Sci Rep, vol. 4, pp.5278-5286, 2014.
 Z. Lu, M. Xu, S. Bao, K. Tan, H. Chai, C. Cai, C. Ji, and Q. Zhang, “Facile preparation of nitrogen-doped reduced graphene oxide as a metal-free catalyst for oxygen reduction reaction”, J Mater Sci, vol. 48, pp. 8101-8107, 2013.
 Q. Yu, J. Xu, C. Wan, C. Wu, and L. Guan, “Porous Cobalt-Nitrogen-Doped Hollow Graphene Spheres as Superior Electrocatalyst for Enhanced Oxygen Reduction in both Alkaline and Acidic Solutions”, Journal of Materials Chemistry A, vol. 3, pp. 16419-16423, 2015.
 H. Jin, H. Huang, Y. He, X. Feng, S. Wang, L. Dai, and J. Wang, “Graphene Quantum Dots Supported by Graphene Nanoribbons with Ultrahigh Electrocatalytic Performance for Oxygen Reduction”, J. Am. Chem. Soc, vol. 137, pp. 7588-7591, 2015.