Enhancement of Capacitive Performance in Titania Nanotubes Modified by an Electrochemical Reduction Method. (4th January 2018)

• Record Type: Journal Article
• Authors: Samsudin, Nurul Asma; Zainal, Zulkarnain; Lim, Hong Ngee; Sulaiman, Yusran; Chang, Sook-Keng; Lim, Ying-Chin; Mohd Amin, Wardatun Nadrah
• Other Names: Sun Xuping Academic Editor.
• Is Part Of: Journal of nanomaterials. Volume 2018(2018)
• Publication Date: 2018-01-04
• Subjects: Nanostructured materials -- Periodicals; Nanotechnology -- Periodicals; Nanomatériaux; Nanostructured materials; Nanotechnology; Nanostructures; Nanotechnology; Periodicals; Fulltext; Internet Resources; Periodicals; 620.115
• DOI: 10.1155/2018/9509126
• Languages: English
• ISSNs: 1687-4110

Abstract

Abstract : Highly ordered titania nanotubes (TNTs) were synthesised by an electrochemical anodization method for supercapacitor applications. However, the capacitive performance of the TNTs was relatively low and comparable to the conventional capacitor. Therefore, in order to improve the capacitive performance of the TNTs, a fast and facile electrochemical reduction method was applied to modify the TNTs (R-TNTs) by introducing oxygen vacancies into the lattice. X-ray photoelectron spectroscopy (XPS) data confirmed the presence of oxygen vacancies in the R-TNTs lattice upon the reduction of Ti 4+ to Ti 3+ . Electrochemical reduction parameters such as applied voltage and reduction time were varied to optimize the best conditions for the modification process. The electrochemical performance of the samples was analyzed in a three-electrode configuration cell. The cyclic voltammogram recorded at 200 mV s −1 showed a perfect square-shaped voltammogram indicating the excellent electrochemical performance of R-TNTs prepared at 5 V for 30 s. The total area of the R-TNTs voltammogram was 3 times larger than the unmodified TNTs. A specific capacitance of 11.12 mF cm −2 at a current density of 20 μ A cm −2 was obtained from constant current charge-discharge measurements, which was approximately 57 times higher than that of unmodified TNTs. R-TNTs also displayed outstanding cycle stability with 99% capacity retention after 1000 cycles.