Nickel oxide(NiO)hollow microspheres with hierarchical structure were fabricated through a process consisting of a self-assembling,hydrothermal reaction and calcination.The prepared NiO hollow microspheres composed of...Nickel oxide(NiO)hollow microspheres with hierarchical structure were fabricated through a process consisting of a self-assembling,hydrothermal reaction and calcination.The prepared NiO hollow microspheres composed of many nanoflakes,are about 2-3μm in diameter.The length of the NiO flakes,having clear edges,is about 500-700 nm,while the thickness is only about 40-50 nm.This indicates that the NiO microspheres possess a hierarchical structure that can provide porous channels to facilitate the transmission of both electrons and electrolyte ions.NiO microspheres exhibit a high specific capacitance of about 1340 F/g at a current density of 1 A/g and high capacitance retention about 96.5%after 1000 cycles.What’s more,the conductive mechanism of nickel oxide for electrochemical capacitor electrodes was also studied.展开更多
基金Xinjiang Uygur Autonomous Region University Scientific Research Project(XJEDU2012I05)National Natural Science Foundation of China(21162027,21063013)
文摘将核壳的聚吡咯基的碳@碳纳米管(C@CNT)与纳米片组装的氧化镍(Ni O)微球结合,制备了一种多孔的锂离子电池负极材料(Ni O/C@CNT),该材料(Ni O/C@CNT)与纯的Ni O和Ni O/CNT相比,其容量值和循环稳定性能明显提高。在50 m A·g-1的电流密度下,经过20次循环后,其可逆容量达到573 m A·g-1,容量保持率为68.6%。这些性能的提高是由于核壳结构的C@CNT的导电缓冲性引起的。C@CNT具有诸如多孔结构、大比表面积、高电化学活性、高电子导电性和良好的浸润性等许多优点,这些优点有利于避免电极材料显著的体积变化,因此在锂嵌入和脱出过程中可减少电极容量衰减并提高传质速率。
基金Project(51274248)supported by the National Natural Science Foundation of ChinaProject(201FA31440)supported by the International S&T Cooperation Program of China
文摘Nickel oxide(NiO)hollow microspheres with hierarchical structure were fabricated through a process consisting of a self-assembling,hydrothermal reaction and calcination.The prepared NiO hollow microspheres composed of many nanoflakes,are about 2-3μm in diameter.The length of the NiO flakes,having clear edges,is about 500-700 nm,while the thickness is only about 40-50 nm.This indicates that the NiO microspheres possess a hierarchical structure that can provide porous channels to facilitate the transmission of both electrons and electrolyte ions.NiO microspheres exhibit a high specific capacitance of about 1340 F/g at a current density of 1 A/g and high capacitance retention about 96.5%after 1000 cycles.What’s more,the conductive mechanism of nickel oxide for electrochemical capacitor electrodes was also studied.