Crystal‐Tuned Spinel Copper Cobaltite with Vertically Aligned Nanoribbons for High‐Performance Asymmetric Coin Cells Evaluated through Experimental and Theoretical Investigations

Abstract The development of sustainable, high‐performance electrode materials is essential for the future of energy storage technologies such as supercapacitors (SCs) and batteries. 1D nanoribbons with unique and fascinating properties are expected to revolutionize future energy technologies. Herein, chemically tuned high‐performance CuCo ₂ O ₄ nanoribbons (CNRs) outperform their counterparts (Co ₃ O ₄ and Cu ₂ O) in SCs due to their high surface area, providing multiple active sites for ion adsorption and redox reactions. The used nickel foam ensures a reliable electrical connection to CNRs and provides 3D‐conductive channels for rapid transport and synergistic effects. The optimized CNR electrode exhibits an impressive capacitance of 1 126 F g ⁻¹ at 3 mA cm ⁻² , retaining ≈93.51% of its capacitance after 50 000 cycles. The asymmetric coin cell SC device (CNRs//activated carbon (AC)) reveals exceptional energy density (ED) and power density (PD) values of 32.2 W h kg ⁻¹ and 517 W kg ⁻¹ , respectively. Furthermore, density functional theory (DFT) based on first‐principle evaluations clarifies that the diverse and unbroken CNRs electrode exhibits enhanced metallic nature. These results establish CNRs as highly promising electrode candidates for next‐generation sustainable and high‐performance energy storage devices.