High-rate and elevated temperature performance of electrospun V2O5 nanofibers carbon-coated by plasma enhanced chemical vapour deposition

• Published in: Nano energy Vol. 2; no. 1; pp. 57 - 64
• Main Authors: Cheah, Yan L., von Hagen, Robin, Aravindan, Vanchiappan, Fiz, Raquel, Mathur, Sanjay, Madhavi, Srinivasan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.01.2013; Elsevier
• Subjects: Applied sciences; Carbon-coating; Catalytic methods; Cathode; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electron and ion emission by liquids and solids; impact phenomena; Electrospinning; Exact sciences and technology; Field emission, ionization, evaporation, and desorption; Li-ion battery; Materials science; Methods of nanofabrication; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; PECVD; Physics; Vanadium pentoxide (V2O5); Electrospinning; PECVD; Vanadium pentoxide (V2O5); Cathode; Carbon-coating; Li-ion battery; Performance evaluation; Lithium ion batteries; Electrical conductivity; Vanadium; Nanofiber; ); Field emission; High temperature; Vanadium pentoxide; Carbon; X ray diffraction; Coated material; Thin film; O; V; Vanadium oxide; Scanning transmission electron microscopy; Performance; Nanostructured materials
• ISSN: 2211-2855
• DOI: 10.1016/j.nanoen.2012.07.012

Vanadium pentoxide (V2O5) nanofibers (VNF) are synthesized by electrospinning technique and homogeneously coated with carbon by plasma enhanced chemical vapour deposition. The morphological features of the VNF are analyzed by field emission scanning and transmission electron microscopy showed the presence of carbon layer over the VNF crystallites. Powder X-ray diffraction (XRD) patterns of the calcined nanofibers reveal the formation of V2O5 phase. Electrochemical Li-insertion behaviors of VNFs are explored as cathode in half-cell configuration by means of both potentiostatic and galvanostatic measurements. Carbon-coated VNF (C-VNF) showed the slightly less initial discharge capacity of ∼300mAhg−1 with improved capacity retention of >65% after 50 cycles at 0.1C rate, whereas native VNF showed only ∼40% capacity retention under the same testing conditions. Enhanced high rate and elevated temperature performance of C-VNF is noted with overall capacity and capacity retention (>60%) characteristics than native fibers. Carbon-coating enables improved electronic conductivity profiles and prevents undesired side reactions with electrolyte counterpart without hindering the Li-ion mobility reflected in the superior battery performance of C-VNF. High performance one dimensional V2O5 nanofibers were prepared by simple electrospinning technique and subsequently carbon coated by plasma enhanced chemical vapor deposition (PECVD). The PECVD procedure provides the uniform carbon layer without destroying its morphology. Carbon coated V2O5 nanofibers (∼5nm) showed enhanced electrochemical performance in ambient and elevated temperature conditions than native fibers. [Display omitted] ► High performance vanadium pentoxide nanofibers (VNF) were prepared by electrospinning technique. ► Carbon coating of VNFs was carried out by PECVD technique. ► Enhanced high rate and elevated temperature performance of C-VNF was noted than native fibers.