中文摘要：

开发有效没有金属的双性人功能的 electrocatalysts 被要求减少费用并且改进慢氧减小反应(ORR ) 和氧进化反应(OER ) 在电气化学的系统的动力学。多孔的做 N 的碳 nanotubes (NCNT ) 被 KOH 激活和 polypyrrole nanotubes 的热分解制作。NCNT 拥有了超过 1,000 的一个大表面区域 ? m ²?g¹ 。NCNT electrocatalysts，特别地，那些在 900 点退火了 ? 椠 ? 捡楴楶祴猠慴敧 ? 湡 ? 祤慮業? 敭档湡獩 ??? 桴獩猠畴祤 ? 敷爠灥牯 ? 桴 ? 牁档慥? ㈨？？

英文摘要：

Developing efficient metal-free bi-functional electrocatalysts is required to reduce costs and improve the slow oxygen reduction reaction （ORR） and oxygen evo- lution reaction （OER） kinetics in electrochemical systems. Porous N-doped carbon nanotubes （NCNTs） were fabri- cated by KOH activation and pyrolysis of polypyrrole nanotubes. The NCNTs possessed a large surface area of more than 1,000 m2 g-1. NCNT electrocatalysts, particu- larly those annealed at 900 ℃, exhibited excellent ORR electrocatalytic performance. Specifically, they yielded a more positive onset potential, higher current density, and long-term operation stability in alkaline media, when compared with a commercially available 20 wt% Pt/C catalyst. This resulted from the synergetic effect between the dominant pyridinic/graphitic-N species and the porous tube structures. The NCNT electrocatalyst also exhibited good performance for the OER. The metal-free porous nitrogen-doped carbon nanomaterials were prepared from low cost and environmentally friendly precursors. They are potential alternatives to Pt/C catalysts, for electrochemical energy conversion and storage.