title: Nitrogen-doped porous carbon from Camellia oleifera shells with enhanced electrochemical performance.
abstract: Nitrogen doped porous activated carbon was prepared by annealing treatment of Camellia oleifera shell activated carbon under NH3. We found that nitrogen content of activated carbon up to 10.43 at.% when annealed in NH3 at 800 °C. At 600 °C or above, the N-doped carbon further reacts with NH3, leads to a low surface area down to 458 m(2)/g and low graphitization degree. X-ray photoelectron spectroscope (XPS) analysis indicated that the nitrogen functional groups on the nitrogen-doped activated carbons (NACs) were mostly in the form of pyridinic nitrogen. We discovered that the oxygen groups and carbon atoms at the defect and edge sites of graphene play an important role in the reaction, leading to nitrogen atoms incorporated into the lattice of carbon. When temperatures were lower than 600 °C the nitrogen atoms displaced oxygen groups and formed nitrogen function groups, and when temperatures were higher than 600 °C and ~4 at.% carbon atoms and part of oxygen function groups reacted with NH3. When compared to pure activated carbon, the nitrogen doped activated carbon shows nearly four times the capacitance (191 vs 51 F/g).
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China. Electronic address: ybzhai@hnu.edu.cn.
authors.forename: Yunbo
authors.initials: Y
authors.lastname: Zhai
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
authors.forename: Bibo
authors.initials: B
authors.lastname: Xu
authors.affiliation: Office of Scientific R&D, Hunan University, Changsha 410082, PR China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
authors.forename: Renpeng
authors.initials: R
authors.lastname: Qing
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Peng
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
authors.forename: Tengfei
authors.initials: T
authors.lastname: Wang
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
authors.forename: Caiting
authors.initials: C
authors.lastname: Li
authors.affiliation: College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Zeng
mesh_terms: D000641:Ammonia / Q000737:chemistry; D028244:Camellia / Q000737:chemistry* / Q000378:metabolism; D002244:Carbon / Q000737:chemistry*; D055664:Electrochemical Techniques; D006108:Graphite / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D009584:Nitrogen / Q000737:chemistry*; D056951:Photoelectron Spectroscopy; D016062:Porosity
chemical_list: D002244:Carbon; D000641:Ammonia; D006108:Graphite; D009584:Nitrogen
keywords: Ammoxidation; Camellia oleifera shell; Capacitance; Nitrogen doping; Oxygen groups