Coprecipitation routed MWCNT/CdMn₂O₄ nanocomposite for high performance aqueous hybrid supercapacitor

A facile coprecipitation approach is used to synthesize CdMn₂O₄ and a multi-walled carbon nanotube/CdMn₂O₄ composite. The prepared CdMn₂O₄ nanoparticles and multi-walled carbon nanotube/CdMn₂O₄ composite are characterized by numerous characterization techniques and discussed. The TEM characterization reveals that CdMn₂O₄ nanoparticles are attached with the multi-walled carbon nanotubes (MWCNTs). Further, the supercapacitive performance of CdMn₂O₄ and MWCNT/CdMn₂O₄ is investigated. High specific capacities (Q_s) of 124.25 and 202 mAh g^-1 are obtained at 1 A g^-1 from CdMn₂O₄ nanoparticles and MWCNT/CdMn₂O₄ composite, correspondingly. The performance of cyclability of MWCNT/CdMn₂O₄ indicates the long durability of the material for commercial application. Further, an aqueous hybrid supercapacitor (HSC) is assembled by MWCNT/CdMn₂O₄ and activated carbon (AC). MWCNT/CdMn₂O₄//AC delivers an energy density of 36.80 W h kg^-1 at the power density of 775 W kg^-1 with the current density of 1 A g^-1. Further, two yellow, two blue, two green, two red and two white color light emitted diodes (LEDs) are easily and separately lighted by two MWCNT/CdMn₂O₄//AC connected in series. As well, a kitchen timer and toy motor fan were powered by two MWCNT/CdMn₂O₄//AC connected in series.