Facile synthesis of a Bi2MoO6/TiO2 nanotube arrays composite by the solvothermal method and its application for high-performance supercapacitor

Abstract

In this study, bismuth molybdate/titania nanotube arrays (Bi₂MoO₆/TNTs) as a binder-free electrode for supercapacitors were fabricated via a facile solvothermal method. The effects of precursor amounts, solvothermal time and temperature on the microstructure and electrochemical properties of the composite were analyzed. The surface morphology, microstructure, chemical composition and chemical states of the composite electrode material were analyzed using scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. Cyclic voltammetry tests, galvanostatic charge–discharge measurements, and electrochemical impedance spectroscopy were employed to analyze the electrochemical behavior of the composite. A specific capacitance of ∼330 mF cm⁻² has been achieved for this Bi₂MoO₆ nanosheets/TNTs composite electrode at the current density of 1 mA cm⁻². Galvanostatic charge–discharge experiments suggest a moderate cycling stability together with 76.7% capacitance retention after 1000 cycles of continuous charge–discharge operation. These results indicate that the Bi₂MoO₆/TNTs composite is a promising electrode material for supercapacitors.