Superior Electrochemical Performance of Doped Anatase Ti0.98M0.02O2 (M=Zr, La, Y) Materials Integrated with Activated Carbon and Carbon Nanotubes for Hybrid Supercapacitor Electrode Material /

Abstract

The popularity of supercapacitors (SC) as energy storage devices stems from their extended cyclic stability, remarkable power densities, and rapid charge and discharge rates. Consequently, significant efforts have put to combine different materials to produce high performance SC composite electrodes. In the present work, anatase Ti0.98M0.02O2 (M= Zr, La, Y) integrated with activated carbon and carbon nanotube has been synthesized via hydrothermal method as high-performance SC electrode material. Different characterization techniques were employed to study the structure, its morphology and surface chemistry along with mass changes during thermal processes. The electrochemical study showed that the as-synthesized Zr@TiO2 electrode material showed the highest capacitive performance of 1326 F g-1at 1 A g-1. It also displayed a columbic efficiency of 83.5 % and an energy density of 16.5 W h Kg-1at the same current density of 1 A g-1. Furthermore, the stability of electrode was tested, and it maintained 85.1% of its performance even after 10000 cycles. This enhanced performance is attributed to its substantial surface area, high conductivity, enhanced structural robustness, and synergistic effects of the components present in the synthesized material. Following successful testing and outstanding performance of the optimal material, the full cell fabrication was also carried out. The full cell shows excellent capacitive performance of 1726 F g-1, at an energy density of 317 W h Kg-1at 1 A g-1and exhibits a stability of 75.2 % after undergoing 10000 cycles.