Electrodeposition of NiCo2O4 nanoparticles on MXene-carbon nanofiber binary composite for high-performance supercapacitor and sodium-ion battery applications
摘要
The present work reports the synthesis of a ternary composite electrode consisting of NiCo2O4 nanoparticles deposited via electrodeposition on MXene-carbon binary nanofibrous composite produced via electrospinning. The effect of electrodeposition time on physicochemical properties including morphology, specific surface area, porosity, functional groups, and ternary phase formation of ternary composite is systematically studied and correlated with the electrochemical performance. The optimized ternary composite shows a uniform distribution of NiCo2O4 nanoparticles and its complete phase formation. The obtained ternary composite electrode is tested as an electrode material for both supercapacitor and sodium-ion battery applications. Its performance is compared with the binary MXene-carbon nanofiber electrodes. The ternary composite electrode demonstrates an excellent specific capacitance of 244 F g−1 at 0.5 A g−1, outperforming the binary MXene-carbon nanofiber electrode (105 F g−1) when tested for supercapacitor applications. It also exhibits a high energy density (21.8 Wh kg−1) at a power density of 430 W kg−1, and excellent cyclic stability by retaining 99% of initial capacitance after 2000 cycles. Further, for sodium-ion battery application, the electrode shows a promising reversible capacity (233 mAh g−1 at 40 mA g−1 current density) and exhibits excellent rate capability when tested as an anode material. The synergistic effect of NiCo2O4, MXene, and carbon nanofiber is responsible for the outstanding electrochemical performance of the ternary composite electrode.