文献类型：期刊文献

英文题名：A green and high energy density asymmetric supercapacitor based on ultrathin MnO₂ nanostructures and functional mesoporous carbon nanotube electrodes

作者：Jiang, Hao[1];Li, Chunzhong[1];Sun, Ting[2];Ma, Jan[2]

机构：[1]E China Univ Sci & Technol, Key Lab Ultrafine Mat, Minist Educ, Sch Mat Sci & Engn, Shanghai 200237, Peoples R China;[2]Nanyang Technol Univ, Sch Mat Sci & Engn, Singapore 639798, Singapore

年份：2012

卷号：4

期号：3

起止页码：807

外文期刊名：NANOSCALE

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000299292600018)】；

基金：This work was supported by the National Natural Science Foundation of China (20925621, 20906027), the Special Projects for Key Laboratories in Shanghai (10DZ2211100), the Shanghai Shuguang Scholars Tracking Program (10SG31), the Basic Research Program of Shanghai (10JC1403300, 10JC1403600), the Shanghai Pujiang Program (09PJ1403200) and the Special Projects for Nanotechnology of Shanghai (1052nm02300).

语种：英文

摘要：A green asymmetric supercapacitor with high energy density has been developed using birnessite-type ultrathin porous MnO2 nanoflowers (UBMNFs) as positive electrode and functional mesoporous carbon nanotubes (FMCNTs) as negative electrode in 1 M Na2SO4 electrolyte. Both of the electrode materials possess excellent electrochemical performances, with high surface areas and narrow pore size distributions. More significantly, the assembled asymmetric supercapacitor with optimal mass ratio can be cycled reversibly in the high-potential range of 0-2.0 V and exhibits an excellent energy density as high as 47.4 W h kg(-1), which is much higher than those of symmetric supercapacitors based on UBMNFs//UBMNFs and FMCNTs//FMCNTs supercapacitors. Furthermore, our asymmetric supercapacitor (ASC) device also exhibits a superior cycling stability with 90% retention of the initial specific capacitance after 1000 cycles and stable Coulombic efficiency of similar to 98%. These intriguing results exhibit great potential in developing high energy density "green supercapacitors" for practical applications.