Nanoengineering of novel MXene (Ti3C2Tx) based MgCr2O4 nanocomposite with detailed synthesis, morphology and characterization for enhanced energy storage application

•XRD clearly indicates both MXene and MgCr2O4 peaks within nanocomposite spectra whereas SEM s shows magnesiochromite particles attachment over MXene nanosheets.•Raman and photoluminescent spectra focused on functional groups existence alongwith maximized electron-hole recombination with bandgap value of 1.8 eV measured from UV spectra.•Peak values for C-F, C–H and MgCr2O4 are visible in FTIR spectra within range 940 cm−1, 2880 cm−1 and 505 cm−1.•Increased electrostatic repulsion designed for colloidal solution as measured by Zeta potential possess value of −19.9 mV.•EIS spectra shows maximum electron transfer rate constant value of 4.097 × 10−9 (cms−1) in IM KOH and 2.66 × 10−9 (cms−1) in 0.1 M H2SO4.•Maximum capacitance value of 542.6F/g is measured in 1 M KOH electrolyte solution at 20 mVs−1 showing its applicability as energy storage material in supercapacitors.