Glucose derived carbon-coated titanium dioxide (GDCC-TiO2) as an advanced electrode material for supercapacitor applications

Abstract

This study examines the advancement and performance of glucose derived carbon- coated titanium dioxide (GDCC-TiO₂) as an advanced electrode material for supercapacitor applications. GDCC-TiO₂ has been fabricated utilizing titanium dioxide and glucose. During the thermal treatment in an inert atmosphere, glucose molecules coated on the surface of titanium dioxide particles are transforming into carbon. Structural analyses ((X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM)) verify the presence of carbon coating on TiO₂ particles. The in-situ carbon coating provides a conductive network around the TiO₂, significantly improving its intrinsic low electrical conductivity while maintaining its high pseudocapacitive properties. The carbon layer enhances ion diffusion, prevents particle agglomeration, and offers structural stability, leading to improved cycling performance and charge-discharge rates. Electrochemical testing, including cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS), reveals that the GDCC-TiO₂ demonstrates the properties of the electrode material utilized in supercapacitor. The specific capacitance of GDCC-TiO₂ reaches a significant value 270.7 F/g at lower scan rate 25 mV/s due to enhanced ion penetration into the pores, while good rate capability is measured at higher scan rates. The GDCC-TiO₂ electrode exhibits a high-power density of 1575 Wkg⁻¹ at energy density of 8.7 Whkg⁻¹.