Synergistic effects of scandium doping and N-rGO integration on titanium oxide and evaluating faradic/non faradic behavior by Dunn's model for high-performance supercapattery applications

Abstract

Supercapacitors have wide-ranging utility in many commercial energy applications. However, despite the remarkable features, researchers are still facing serious challenges regarding the charge-storing potential of these devices. In the current research work, we mainly paid attention to the materials having high porosity and larger surface area, as these features make them electrochemically ideal supercapacitor materials with greater energy-storage potential. For this purpose, titanium oxide (TiO₂), scandium-doped TiO₂ (ScTi), and N-rGO-doped ScTi (ScTi/N-rGO) nanostructures are efficiently synthesized through simple sol-gel and hydrothermal method. Electrochemical results show that ultra-capacitors based on ScTi/N-rGO electrodes have the highest specific capacitance (Csp) ScTi/N-rGO with 1595.37 Fg⁻¹ at 1 A/g. Dunn's model is used to assess the relative contributions of faradic and non-faradic processes in electrochemical reactions and their results showed that the prior operating system is larger than the later one that delineated the battery-grade nature of doped ScTi/N-rGO. Additionally, two electrode symmetric analyses depicted Csp 998.56 F g⁻¹ at 1 Ag⁻¹ and retained 88.92 % capacity after 6000 cycles. Thus, the results of this work also unveil that the electrochemical performance of the optimized ScTi/N-rGO nanocomposites is linked with the two prime factors entailing the optimization of N-rGO and scandium doping. Furthermore, it upsurges the TiO₂ conductivity as well as enhances the structural porosity which in turn increases the specific surface area. Thus, it is concluded that findings could be potential enough to indicate the vast array of possible electrochemical usage of synthesized porous ScTi/ N-rGO nanostructures.