Bottom–up assembly of strongly–coupled Na3V2(PO4)3/C into hierarchically porous hollow nanospheres for high–rate and –stable Na–ion storage. (September 2017)

• Record Type: Journal Article
• Authors: Wei, Tongye; Yang, Gongzheng; Wang, Chengxin
• Is Part Of: Nano energy. Volume 39(2017:Sep.)
• Page Start: 363
• Page End: 370
• Publication Date: 2017-09
• Subjects: Sodium ion battery -- Cathode -- Na3V2(PO4)3 -- High-rate performance; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2017.07.019
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Herein, a three–dimensional (3D) Na3 V2 (PO4 )3 –based hollow nanosphere with hierarchical pores (3DHP–NVP@C) has been firstly reported. Detailed studies reveal that this novel architecture is made up from the bottom–up assembly of carbon–coating NVP nanoparticles. The hierarchically porous structure offers ample space for the intimate contact between electrode/electrolyte and eliminates the disadvantageous reducing of effective surface areas in manufacturing the electrodes, as well as stabilizes the structure upon repeated sodium ions insertion/extraction, resulting to the barrier–free sodium ion diffusions and long–term cycling life. On the other hand, the graphitic carbon shells construct into a highly–conductive framework that can ensure the ultrafast electrons transfer. Consequently, extraordinary high–rate and ultralong–cycle capabilities that are superior to any other NVP–based material are obtained: the outstanding high–rate capacity retention (over 80% of the 1 C capacity is retained at 400 C), ultralong life span (90.9% and 92.5% capacity retention after 10, 000 cycles at 1 C and 5 C), and extremely high–rate stability (80% capacity retention after 30, 000 cycles at 50 C), demonstrating its promising application in sodium ion battery. Graphical abstract: Highlights: For the first time, we reported a controllable heteroepitaxial nucleation of NVP on graphene oxide nanosheets. The strongly–coupled NVP/C and bottom–up assembly together contributed to a highly–conductive nanocomposite. The NVP/C nanocomposite demonstrate an extraordinarily high-rate and long-durability Na-storage performances.