Theory abide experimental investigations on morphology driven enhancement of electrochemical energy storage performance for manganese titanate perovskites electrodes

Abstract

The ultrathin 2D morphologies are found efficient in delivering better specific energy and long cycle life performance for supercapacitors. Therefore, we report the effect of morphological transformation from nanoparticles to ultrathin nanodiscs of MnTiO3 (MTO) perovskites as an efficient electrode for electrochemical supercapacitor where the interconnected network of stacked ultrathin 2D nanodiscs provided easily accessible sites for efficient diffusion of OH− ions deep inside the electrode material. Ultrathin 2D MTO nanodiscs delivered a specific capacitance of 1513.7 F/g, specific capacity of 103.2 mAh/g, specific power of 1351.9 W/kg, and specific energy of 52.2 Wh/kg. Moreover, 85.1% capacitance retention after 5000 cycles in 2 M aq. KOH electrolyte was observed with insignificant morphological deformation of 2D nanodiscs. Corresponding First-principles density functional theory (DFT) calculations revealed that ultrathin 2D morphology produced higher work-function and hence delivered better energy storage performance. © 2022 Elsevier B.V.