Ultrafast synthesis of amorphous VOx embedded into 3D strutted amorphous carbon frameworks–short-range order in dual-amorphous composites boosts lithium storage. Issue 16 (5th April 2018)

• Record Type: Journal Article
• Authors: Wu, Haoyang; Qin, Mingli; Wang, Wei; Cao, Zhiqin; Liu, Zhiwei; Yu, Qiyao; Lao, Chengyen; Zhang, Deyin; Jia, Baorui; He, Donglin; Liu, Tingting; Volinsky, Alex A.; Cao, Peng; Qu, Xuanhui
• Is Part Of: Journal of materials chemistry. Volume 6:Issue 16(2018)
• Page Start: 7053
• Page End: 7061
• Publication Date: 2018-04-05
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c8ta00654g
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : Dual-amorphous VO x /carbon composites were synthesized by a SCS technique for superior lithium-ion batteries. Abstract : Crystalline vanadium oxides have some unique advantages, including abundant material sources, high energy density, and a typical layered structure, making them promising anode candidates for lithium-ion batteries. However, the intrinsic low electrical conductivity and volume expansion side effects severely limit their capacity and cyclability at high charge/discharge rates. Herein, unique dual-amorphous composites with 3D strutted amorphous carbon sheet framework encapsulated amorphous vanadium oxide particles have been prepared by an ultrafast (within one minute), ultralow temperature (172 °C), one-step and large-scale combustion synthesis method. We demonstrate that the dual-amorphous VO x /C composites provide a large number of accessible active sites and defects for lithium ion intercalation/deintercalation and are self-accommodative to tolerate volume expansion. Another noteworthy point is the short-range ordered atomic arrangement observed in amorphous VO x that exhibits a larger interlayer spacing ( d (001) = 4.80 Å) than other crystalline vanadium oxides. This particular structure has the potential to accommodate more lithium ions and tolerate the volume expansion. Meanwhile the 3D hierarchical porous sheet-like structure facilitates the transfer of electrons and lithium ions. The electrochemical measurements show excellent lithium storage performance with high capacity, good rate capability and long-term cycling stability of the composites.