Enhancing Carbon-Based Electrode Fabrication on Porous Nickel Foam: The Role of TiO2 in Electrochemical Deposition

Abstract

Supercapacitor electrodes were fabricated on porous nickel foam via electrochemical deposition using activated carbon (AC), graphene oxide (GO), reduced graphene oxide (rGO), and their TiO2 composites. While AC, GO, and rGO exhibit promising attributes, they also have intrinsic limitations. AC provides a high surface area but suffers from low conductivity and an irregular pore structure, hindering electron transport and electrolyte access. GO's oxygenated functional groups enhance hydrophilicity but reduce conductivity and electrochemical performance. rGO offers superior conductivity and mechanical strength but has a lower active surface area and limited ionic interaction, reducing specific capacitance. TiO2 incorporation mitigates these issues: in AC, it improves pore structure for better electrolyte penetration; in GO, it reduces oxygen group effects, enhancing conductivity; in rGO, it increases wettability, promoting ion transfer and boosting capacitance. Among the electrodes, the rGO-TiO2 composite achieved the highest specific capacitance of 390 F g-1 at 3 mA, while bare rGO exhibited outstanding cyclic stability, retaining 98% capacitance after 1800 cycles. TiO2 composites enhance supercapacitor electrode performance by improving conductivity, surface wettability, and pore structure of activated carbon (AC), graphene oxide (GO), and reduced graphene oxide (rGO).rGO-TiO2 composite achieves the highest specific capacitance of 390 F g-1 at 3 mA, showing superior energy storage potential.rGO electrodes demonstrate exceptional cyclic stability, retaining 98% of their initial capacitance after 1800 cycles.GO-TiO2 electrode reaches high energy (165.6 Wh kg-1) and power densities (12.6 kW kg-1), enhancing overall supercapacitor efficiency.TiO2 addition boosts electrolyte accessibility and improves the electrochemical performance of carbon-based supercapacitor electrodes.