Synthesis and Capacitive Properties of Mesoporous Tungsten Oxide Films Prepared by Ultrasonic Spray Deposition

[Image: see text] Mesoporous tungsten trioxide (WO(3)) films are prepared by the combination of the template-assisted sol–gel method and ultrasonic spraying deposition (USD) for supercapacitors, and then the surface morphology and electrochemical performance of the films are studied. Compared to WO(3) prepared by the traditional hydrothermal synthesis and spin coating method, the films obtained by USD exhibit advantages such as low cost, minimal material usage, and suitability for large-area in-line manufacturing. Additionally, the mesoporous structure of USD-produced films is also supportive of ion transportation. Due to the high specific surface area of WO(3) films deposited by USD, it is a material capable of use in a high-performance energy storage device. Through the control of spray coats, the film thickness and specific capacitance can be effectively controlled. Electrochemical measurements show that the mesoporous WO(3) films possess excellent electrochemical performance with a maximum specific capacitance of 109.15 F/g at 0.5 A/g. The cycling performance up to 5000 cycles of mesoporous WO(3) films is due to the stable nature of nanocrystalline produced by the combination of USD and sol–gel chemistry.