Laser-Assisted Rapid\nFabrication of Cobalt Hydroxide@Carbon\nFiber Composites for High-Performance, Robust Structural Supercapacitors

Conventional supercapacitor electrodes often rely on\ntime-consuming\nhydrothermal methods to create nanostructures. In this study, a laser-assisted\nprocess was utilized to fabricate cobalt hydroxide on a carbon fiber\n(CF) composite, achieving a mechanically stable structural capacitor\n(SSC) within 50 min. Intensive CO<sub>2</sub> laser irradiation facilitated\nthe rapid deposition and growth of diverse nanoarchitectures on the\nCF substrate. The outstanding performance of the Co(OH)<sub>2</sub>@CF electrode was demonstrated by its rate capability, with a cyclic\nstability of 96.3% maintained through 15,000 cycles and a Coulombic\nefficiency of 99.5%. A high specific capacitance of 1448.20 F g<sup>–1</sup> was also observed. The unique morphology of the Co(OH)<sub>2</sub>@CF electrode enabled efficient charge storage with a high\ndiffusion contribution, even at 50 mV s<sup>–1</sup>. The robust\nSSC device remained stable under external forces and thus showed promise\nin addressing the sensitivity issues encountered with current supercapacitor\ndevices.