ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Fabrication, characterisation, and electrochemical performance of redox active broccoli-shaped WSe₂ for supercapacitor application

Helen Treasa Mathew, Shashikant Shivaji Vhatkar, Kumar Abhisek, and Ramesh Oraon

Department of Metallurgical and Materials Engineering, Central University of Jharkhand, Cheri-Manatu, Ranchi, India

E-mail: ramesh.oraon@cuj.ac.in

Received: 7 April 2025  Accepted: 5 October 2025

Abstract:

Recently, transition metal dichalcogenides (TMDs) with their exceptional properties like increased electrical conductivity, large surface area, well-defined dimensionalities, and the availability of variable oxidation states have attained popularity for being a promising candidate in various energy storage applications. Herein, we report the hydrothermal synthesis of broccoli-shaped Tungsten Selenide (WSe₂) that ensures the formation of finely structured material with fewer impurities. Bonding and structural properties of the material were analysed by FTIR and XRD analysis which revealed the hexagonal lattice formation of WSe₂. This observation was well complemented by downward Raman peak shift (~ 343 cm⁻¹) indicating the multilayered structure of WSe₂. Furthermore, morphological feature by FESEM revealed stacked layering (due to interplanar atomic interaction) to form aggregates resembling broccoli structure. Band gap was calculated to be 2.61 eV by Tauc plot in good agreement with previous report. The electrochemical behaviour was evaluated by cyclic voltammetry, charge discharge, and impedance spectroscopy employing three electrode configurations in aqu. 1 M KCl solution. Within potential window (− 0.2 to 0.6 V) presence of typical quasi-rectangular voltammogram and non-linear charge discharge profile augments the charge storage and redox behaviour of WSe₂. Maximum specific capacitance was calculated to be 65.5 F/g at 0.4 A/g. This was further validated by low charge transfer resistance and phase angle (closer to 90° by bode plot). Overall good electrochemical response could be attributed to facile migration of electrolyte ions within the conducting layered structure of self-assembled broccoli shape WSe₂.

Keywords: Tungsten selenide (WSe2); Hydrothermal; Cyclic voltammetry; Charging-discharging; Supercapacitor

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04426-5

Chemical Papers 80 (1) 757–767 (2026)