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

Supercapacitor electrodes were fabricated on porous nickel foam via electrochemical deposition using activated carbon (AC), graphene oxide (GO), reduced graphene oxide (rGO), and their TiO 2 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. TiO 2 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-TiO 2 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.