文献类型：期刊文献

英文题名：Nanoarchitectured Nb2O5 hollow, Nb2O5@carbon and NbO2@carbon Core-Shell Microspheres for Ultrahigh-Rate Intercalation Pseudocapacitors

作者：Kong, Lingping[1];Zhang, Chuanfang[1];Wang, Jitong[1];Qiao, Wenming[1,2];Ling, Licheng[1,2];Long, Donghui[1,2]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Key Lab Specially Funct Polymer Mat & Related Tec, Shanghai 200237, Peoples R China

年份：2016

卷号：6

外文期刊名：SCIENTIFIC REPORTS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000370176200002)】；PubMed(收录号：26880276);

基金：This work was partly supported by MOST (2014CB239702) and National Science Foundation of China (No. 51302083, No. 51172071, No. 51272077), and Fundamental Research Funds for the Central Universities and Shanghai Rising-Star Program.

语种：英文

摘要：Li-ion intercalation materials with extremely high rate capability will blur the distinction between batteries and supercapacitors. We construct a series of nanoarchitectured intercalation materials including orthorhombic (o-) Nb2O5 hollow microspheres, o-Nb2O5@carbon core-shell microspheres and tetragonal (t-) NbO2@carbon core-shell microspheres, through a one-pot hydrothermal method with different post-treatments. These nanoarchitectured materials consist of small nanocrystals with highly exposed active surface, and all of them demonstrate good Li+ intercalation pseudocapacitive properties. In particular, o-Nb2O5 hollow microspheres can deliver the specific capacitance of 488.3 F g(-1), and good rate performance of 126.7 F g(-1) at 50 A g(-1). The o-Nb2O5@carbon core-shell microspheres show enhanced specific capacitance of 502.2 F g(-1) and much improved rate performance (213.4 F g(-1) at 50 A g(-1)). Furthermore, we demonstrate for the first time, t-NbO2 exhibits much higher rate capability than o-Nb2O5. For discharging time as fast as 5.9 s (50 A g(-1)), it still exhibits a very high specific capacitance of 245.8 F g-1, which is 65.2% retention of the initial capacitance (377.0 F g(-1) at 1 A g(-1)). The unprecedented rate capability is an intrinsic feature of t-NbO2, which may be due to the conductive lithiated compounds.