| Ordered mesoporous carbon ?OMC? not only contain common properties of carbon materials, but also with high specific surface area, uniform pore size, ordered pore distribution and other unique characteristics that they can be used in catalysis, separation, adsorption, photoelectric transformation, energy transformation and storage. The atomic structure of carbon materials is controllable so that it can be doped by hetero-atoms while the outermost electrons structure of carbon atoms can be changed to bring excellent physical and chemical properties. In this paper, triblock copolymer as soft template to prepare boron doped ordered mesoporous carbon ?BOMC?. Meanwhile, electrochemical performance was studied while the influence of different structures on capacitor performance. Then, ?Fe, N, B? co-doped ordered mesoporous carbon ??Fe,N,B?-OMC? catalysts were prepared, and their the catalytic performance of oxygen reduction reaction ?ORR? and catalytic mechanism was studied. The main results are listed as follows: ?1? OMC was prepared by tribolck polymer F127 as soft template and the influence of phenolic resin ratio on structure was studied. Further research on the effect of carbonization temperature to the structure, and the 2-D hexagonal mesostructure of platelike OMCs was prepared which their surface area range from 682.32 to 398.06 m2·g-1, and pore volume 0.526 to 0.241 cm3·g-1, and pore size 5.6 to 4.4 nm all declined following increasing temperature for their poor stability.?2?Phenolic resin was thermosetted and modified through esterification reaction between boric acid and hydroxybenzyl as "Bridging" in order to improve the stability of the mesostructure and achieve in-situ boron doping by B-O-C bond in the T-crosslinking phenolic resin network after carbinization. Therefore, more stable and extended 2-D hexagonal mesostructure of the plate-like BOMC was prepared which surface area range from 396.33 to 641.03 m2·g-1. Specific capacitance of BOMC reach to 162.12 F·g-1 that twice more than OMC because BOMC mesoporous surface area increased and B-C, B-O-C bonds changed the form of chemical bond in carbon material and the capacitance retention of production enhanced by doping boron.?3?Washed boron doped mesoporous carbon?WBOMC? by acid improved the connectivity between production's channels and promoted mass transfer and electron conduction. And a large number of microporous was formed at the same time the surface area increased 71.8% result that the capacitance performance of it had been improved 11%. Moreover, the sample retained 161 F·g-1 with a retention rate of 96.6% after 10000 cycles (5 A·g-1), indicating the excellent retention capability under high current density and long cycle life. The acidized boron doped mesoporous carbon?ABOMC? was prepared by acidification that the surface chemical component had been changed by oxygen functional groups and the hydrophilicity of surface had been improved while mass transfer benefited. Meanwhile the surface area increased 63.2% and the pore diameter narrowed to 4.2 nm because the surface of channels was modified by oxygen functional groups. The capacitance of it got to 318 F·g-1 and the energy density reached 22.52 Wh·Kg-1.?4? ?Fe,N,B?-OMC catalyst was synthesized by 8-hydroxyquinoline Ferric ?III? as precursor while the Fe-N structures were taken to be sites of the catalytic activity after carbonized.80%?Fe,N,B?-OMC got the best structure and composite in the study of the influence of precursor ratios to the catalysts which it contain highest Fe reach to 0.47% and surface area was 315.68 m2·g-1 so that it showed closed ORR catalytic activity to commercial Pt/C. The ?Fe,N,B?-OMC catalyzed the ORR proceed through four-electron pathway and it showed higher stability than commercial Pt/C catalyst through the studies on the catalytic mechanism and the stability. |
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