2D TiO₂/Zn₃V₂O₈ flake-like composites for hybrid storage device and simulation-based analysis of capacitive and diffusive contribution

Current electrochemical energy storage technology necessitates the development of a single energy system capable of meeting the high electrochemical efficiency demands of high energy density, power density, and long cyclic stability. To meet these requirements, it is highly desirable to develop new energy storage materials as well as understand the multiple charge storage mechanism in these materials. In this study, titanium dioxide‑zinc vanadate nanocomposites were synthesized as high electrochemical efficiency electrode materials. The electromechanical measurements showed an improved specific capacity of 525 Cg⁻¹ for TiO₂/Zn₃V₂O₈ nanocomposite as compared to 400 Cg⁻¹ for Zn₃V₂O₈ at a current density of 1 Ag⁻¹. The outstanding power density of 6562 WKg⁻¹ with 66 WhKg⁻¹ energy density was attained at 1 Ag⁻¹. Moreover, the assembled device shows excellent performance by achieving 114.11 Whkg⁻¹ energy density and 2600 Wkg⁻¹ power density at 1 Ag⁻¹. The practical viability of the device is demonstrated by fabricating the asymmetric coin cell which can operate the commercially available calculator for ~21 min. Additionally, MATLAB simulations at different voltage step potentials are performed to elucidate the charge storage mechanism which shows higher accuracy as compared with the conventional methods.