Binder-free CoMn2O4/carbon nanotubes composite electrodes for high-performance asymmetric supercapacitor

•CoMn2O4 nanosheets are electrodeposited onto carbon nanotubes/stainless-steel mesh.•Direct growth of CoMn2O4 on carbon nanotubes prevents the use of binders.•The effect of deposition time on morphology and capacitance is investigated.•The electrode shows high specific capacitance of 732 F/g at a scan rate of 2 mV/s.•The asymmetric supercapacitor exhibits a high energy density of 47.39 W/kg.