Nickel-infused cobalt ferrite/MXene nanocomposites: Structural insights and electrochemical properties for high performance supercapacitors

In view of the unique magnetic characteristics of the ferrites, inverse spinel cobalt ferrite/MXene nanocomposites (Co_1-xNi_xFe₂O₄/MXene NCs) have garnered significant attention. These vital characteristics make Co_1-xNi_xFe₂O₄/MXene NCs an ideal material for supercapacitor application. To synthesize Co_1-xNi_xFe₂O₄/MXene NCs, a simple and cost-effective low-temperature co-precipitation approach was used, and samples were synthesized at different nickel concentrations (x = 0.03, 0.05, 0.07, 0.10) further integrated with MXene. Several characterization studies were used to investigate their crystallinity, morphology, and electrochemistry using different techniques such as X-ray powder diffraction (XRD), Fourier transform infrared spectrum (FT-IR), elemental composition analysis (X-ray photoelectron spectra - XPS), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Co_1-xNi_xFe₂O₄ (x = 0.10) with MXene exhibited smaller crystallite size compared to other produced samples. The results showed that increase in nickel concentration decreases the crystallite size and lattice constant. The FT-IR spectra showed two strong absorption bands near 560 cm⁻¹ (v₁) and 400 cm⁻¹ (ν₂). SEM was used to corroborate the shape of the cubically spherical structure. The electrochemical behaviour for the produced samples were investigated using cyclic voltammetry (CV) with a electrolyte solution of 1 M KOH. The voltage has been constrained to 0.0 volts to 0.5 volts, with potential scan speeds ranging 5, 10, 20, 25, 50, and 75 mV/s. A cyclic voltametric investigation found that the nickel doped cobalt ferrite with MXene incorporation enhanced the specific capacitance over Co_1-xNi_xFe₂O₄ (x = 0.10). The specific capacitance of nickel-doped cobalt ferrite (x = 0.10) and (x = 0.10/MXene) samples were 361C g⁻¹ and 367C g⁻¹ respectively.