Preparation Of Heteroatom-doped Carbon Materials And Study Of Their Electrochemical Performance

The incomparable advantages of carbon-based materials endow them with broad application prospects over inorganic materials or metals in energy-related fields.Heteroatom-doping will enhance intrinsic excellent properties and add new features to carbonaceous materials,thus making the best of their potential.Based on existing research achievements and aiming at solving deficiencies of this domain,this paper intended to design new carbon-material systems and carbon materials with different dimensions,thus achieving control of heteroatom types and doping amounts in carbon matrix as well as template-directed construction of one-dimensional(1D)or two-dimensional(2D)carbon nanomaterials.The main contents and results are listed as follows.1.Nitrogen-doped carbon-encapsulated Sn O2–Sn S/graphene sheets with improved anodic performance in lithium ion batteries: A novel dualdoping approach for nitrogen-doping carbon-coated Sn O2-Sn S/graphene nanosheets(N-C@Sn O2-Sn S/GN)was developed,which realized simultaneous nitrogen-doping of carbon shell and sulfur-doping of Sn O2-decorated graphene core through a facile approach.Used as the anode material in lithium ion batteries(LIBs),N-C@Sn O2-Sn S/GN delivers excellent cycling stability and rate performance,which outperforms most state-of-art tin-based LIB anodes with core-shell structures.2.Nitrogen-doped porous carbon frameworks with different dimensions as efficient oxygen reduction reaction catalysts: Onedimensional(1D)and two-dimensional(2D)nitrogen-doped porous carbon materials 1D-NPC and 2D-NPC were constructed by adopting nitrogen-containing monomers as well as taking poluacrylonitrile-functionalized carbon nanotube and graphene as structure-directing templates.Used as ORR catalysts,2D-NPC showed a high electrochemical catalytic activity comparable to commercial Pt-C electrode,which surpassed its 1D counterpart.It is thus proved that the electrochemical catalystic performance of nitrogen-doped carbon material can be effectively regulated by adjusting its specific surface area,pore size and nitrogen configuration in carbon matrix,which could be achieved by changing its dimensionality.3.Porous carbon frameworks doped with different heteroatoms as lithium ion battery cathodes: We prepared nitrogen-doped porous carbon(CTF-B,CTF-P)with different nitrogen-doping amounts and nitrogen/sulfur-co-doped porous carbon(CTF-T)by applying three types of monomers as precusors for ionthermal polymerization.The obtained samples were detected as cathode materials of lithium ion battery,it turns out that increasing the doping amount of nitrogen atoms or introducing nitrogen/sulfur atoms simultaneously into porous carbon matrix could significantly improve the electrochemical performance of cathode materials,which represents valuable exploration in the field of lithium ion battery cathodes.