Abstract Taking ZnO nanorods as a template, N-doped and porous carbon sheets (NPCS) were obtained by high-temperature carbonization and KOH activation of ZIF-8@ZnO hybrids. The morphology, structure and elemental composition of the as-obtained NPCS were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and N2 adsorption analyzer. The NPCS showed a large specific surface area (1190 m2 g− 1), high specific capacitance of 290 F g− 1 at current density of 1 A g− 1, and superior charge–discharge cycle stability (the capacitance retains 94% after 10,000 cycles at a high current density of 20 A g− 1). Furthermore, the NPCS//NPCS two-electrode symmetric supercapacitor also showed high energy density and power density, and excellent rate performance of 81.9% capacitance retention when the current density was increased from 0.5 to 50 A g− 1. These suggested the great potential applications of NPCS in high-performance electrochemical supercapacitors.

中文翻译：

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ZIF-8 衍生的 N 掺杂多孔碳片：制备及其电化学电容性能

摘要 以ZnO纳米棒为模板，通过ZIF-8@ZnO杂化物的高温碳化和KOH活化得到N掺杂多孔碳片（NPCS）。通过扫描电子显微镜、透射电子显微镜、X 射线衍射、X 射线光电子能谱和 N2 吸附分析仪对所获得的 NPCS 的形貌、结构和元素组成进行了表征。NPCS 显示出较大的比表面积 (1190 m2 g−1)，在 1 A g−1 的电流密度下具有 290 F g−1 的高比电容，以及优异的充放电循环稳定性（10,000 次后电容保持 94%在 20 A g- 1 的高电流密度下循环。此外，NPCS//NPCS双电极对称超级电容器还表现出高能量密度和功率密度，以及81的优异倍率性能。