Design of interfacial cobalt oxide on titanium boride hybrid nanocomposites for enhanced electrochemical performance

We developed an interfacial cobalt oxide (Co₃O₄) and exfoliated titanium diboride (TB) hybrid composite (TBC HC) electrode material using a precipitation-assisted hydrothermal method to evaluate its electrochemical energy storage performance. Different TBC HCs were synthesized by varying the weight ratio of Co₃O₄ to TB (85: 15, 75:25 & 50:50). Structural characterization of the TBC HCs was performed using FTIR, XPS, XRD, FE-SEM, EDS, and FE-TEM. The resulting TBC HC electrode materials exhibited a hierarchical morphology with uniformly distributed Co₃O₄ nanoparticles at the TB interface. Electrochemical performance was studied using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). Among the composites, the TBC2 HC (75:25) displayed a superior specific capacitance (Cs) of 1152.2 F/g at 0.5 A/g, outperforming pristine TB (189.2 F/g) and Co₃O₄ (629.6 F/g) in a three-electrode configurations using 1 M KOH electrolyte. Furthermore, a symmetric solid-state device (SSD) constructed with TBC2 HC (75:25)//TBC2 HC (75:25) delivered a specific capacitance of 256.1 F/g at 0.5 A/g, achievening a maximum energy density of 10.4 Wh/kg and a power density of 540.4 W/kg. The device maintained 87 % of its initial capacity after 10,000 charge-discharge cycles, demonstrating strong potential for energy-storage applications.