Tungsten Disulfide Wrapped WO 3 Based Thin Film Transparent Electrode Material for Electrochromic Device Application

• Published in: Journal of the Electrochemical Society Vol. 170; no. 3; p. 36504
• Main Authors: Sharma, Rahul, Nihal, Sharma, Mamta, Goswamy, J. K.
• Format: Journal Article
• Language: English
• Published: 01.03.2023
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1945-7111/acbee3

We report the detailed investigation of tungsten disulfide (WS 2 ) wrapped tungsten trioxide (WO 3 ) nanocomposites as electrode materials for electrochromic devices. The WS 2 /WO 3 nanocomposite was prepared by exfoliation of WS 2 in WO 3 , where WO 3 was prepared by acidic co-precipitation technique. X-ray diffraction spectra were used to study the structural properties of the prepared materials. The results show that agglomeration due to pinning of grain boundaries by WS 2 leads to an increase in the crystallite size of the nanocomposites, confirming the formation of WS 2 /WO 3 . Field-emission scanning electron microscopy and high-resolution tunnelling electron microscpy were used to study the nanocomposites morphology. The results show that the relative distribution of nanoparticles is more uniform compared to WO 3 after the addition of WS 2 . The shape of WO 3 changes from spherical to square nanosheets with good dispersion. The electrochemical properties of the prepared samples were investigated by chronoamperometry, charge/discharge,and cyclic voltammetry. The lower peak separation between oxidation and reduction resulted from the fact that the peaks of the anodic and cathodic current densities of the nanocomposite (WS 2 /WO 3 ) were shifted more to higher and lower potentials, respectively. This suggests faster charge transfer kinetics. UV/Vis spectroscopy was used to investigate the electrochromic and optical properties of the fabricated ECDs. The WS 2 /WO 3 -based ECDs exhibit a high colouring efficiency of 61 cm 2 C −1 . The study shows that ECDs based on WS 2 /WO 3 exhibit better electrochromic performance compared to WO 3 ECDs.