Supercapacitor is the best potential candidate of the energy storage system due to the superior charge or discharge efficiency, high power density (>10 kW kg-1), and long cycling life. Porous carbon materials as the promising electrode material have been widely used in supercapacitor. In fact, conventional porous carbon supercapacitor electrodes cannot fulfil the growing demand of high energy and power densities of supercapacitor. A large number of studies show that nitrogen doping can change the surface electronic structure of carbon materials, thus significantly improving the electrochemical properties. In addition to, the pore structure and morphology of carbon materials have great influence on the electrochemical performance. In this work, we firstly fabricated nitrogen-doped porous carbon nanotubes by using a simple mixed salts (NaCl/ZnCl2) activation strategy. The as-obtained porous carbon nanotubes exhibited excellent electrochemical performance in supercapacitor. Furthermore, two- dimension nitrogen-doping porous nanosheets were prepared by a salt template-assisted monomer deposition method. In this study, by optimizing the synthesis conditions, the as-obtained carbon nanosheets showed a high specific capacitance of 277 F g-1 at 1 A g-1 and excellent cycle stability retained 91 % after 10,000 cycles. / College of Engineering, Science and Technology / M. Tech.( Civil and Chemical Engineering

Within the different available electrochemical energy storage systems, supercapacitors stand out due to their high power densities and ultra-long cycle life. Their key-components are the electrode materials where the charge accumulation takes place and therefore many different approaches for the synthesis of carbonaceous electrode structures with well-defined pore systems are available. This review focuses on different strategies for tailoring porous carbon materials from the micropore level, over mesopores to macropores and even external or inter-particular porosity. A wide range of materials such as activated carbons, templated carbons, carbide-derived carbons, carbon nanotubes, carbon aerogels, carbon onions, graphenes and carbon nanofibers are presented, always in relation to their pore structure and potential use in supercapacitor devices.

Nous avons montré les performances et les limitations en électrochimie des deuxnouvelles BODs de Bacillus pumilus et de Magnaporthe oryzae. La BOD de M.oryzae commence à réduire l’O2 à un potentiel de + 0,50 V vs. Ag/AgCl et B. pumilusà + 0,44 V vs. Ag/AgCl. La BOD de M. oryzae est peu sensible à la concentration dephosphate de sodium dans l’hydrogel rédox mais est sensible au chlore, à l’urate etaux fortes température. La BOD de B. pumilus a une activité élevée en présence dechlore et à 50 °C mais est sensible à la concentration de phosphate dans l’hydrogel.Cette sensibilité est compensée par une meilleure stabilité en présence d’urate, ainsielle ne perd que 9 % d’activité après 3 heures dans le sérum de veau. La BOD de M.oryzae immobilisée sans médiateur est plus performante que B. pumilus. Sonutilisation dans des nouveaux carbones poreux contenant des nanoparticules d’or amis en évidence l’effet des conditions de séchage des enzymes et de la méthode desynthèse des nanoparticules. Les meilleures performances sont obtenues pour unséchage à 25 °C sous vide et une synthèse séquentielle des nanoparticules. Nousavons combiné ces deux BODs dans une nouvelle cathode bi-enzymatique. Au ratiooptimal de 50 %v de chaque BOD, elle opère à + 0,50 V vs. Ag/AgCl avec un courantde -0,86 ± 0,01 mA.cm-2 dans les conditions physiologiques. Elle a une forte activité àhaute température et en présence de chlore et une stabilité intermédiaire enprésence d’urate. Dans les mêmes conditions nous avons réalisé une cathode bienzymatiqueavec B. pumilus et la laccase de Podospora anserina. Elle estégalement plus performante que les cathodes mono-enzymatiques correspondantes. / Here we showed the performances and the limits in electrochemistry of the two newBODs from Bacillus pumilus and Magnaporthe oryzae. The onset potential for theoxygen reduction with the BOD from M. oryzae is + 0.50 V vs. Ag/AgCl and with B.pumilus is + 0.44 V vs. Ag/AgCl. The BOD from M. oryzae is not sensitive to theconcentration of sodium phosphate in redox hydrogel but is sensitive to chloride,urate and high temperatures. The BOD from B. pumilus has a high activity in thepresence of chloride and at 50 °C, but is sensitive to the concentration of phosphatein the hydrogel. This sensitivity is offset by an improved stability in the presence ofurate, so it loses only 9 % of activity after 3 hours in calf serum. The BOD from M.oryzae immobilized without mediator outperforms B. pumilus. Its use in new porouscarbon materials containing gold nanoparticles showed the effect of enzymes dryingconditions of the synthesis method of the nanoparticles. The best performance isobtained for a drying at 25 °C under vacuum and a sequential synthesis ofnanoparticles. We combined these two BODs in a new bi-enzymatic cathode. At theoptimal ratio of 50 %v of each BOD, it operates at + 0.50 V vs. Ag/AgCl with a currentdensity of -0.86 ± 0.01 mA.cm-2 under physiological conditions. It has a high activityat high temperatures and in the presence of chloride and an intermediate stability inthe presence of urate. Under the same conditions we conceived a bi-enzymaticcathode with B. pumilus and laccase Podospora anserina. It is also more efficientthan the single-enzymatic corresponding cathodes.