Mesoporous 3D NiCo₂O₄/MWCNT nanocomposite aerogels prepared by a supercritical CO₂ drying method for high performance hybrid supercapacitor electrodes

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>A facile sol-gel route is developed to build mesoporous 3D NiCo<SUB>2</SUB>O<SUB>4</SUB>/MWCNT nanocomposite aerogels. The crystal structure, surface morphology and electrochemical performance of the aerogel composites are investigated by X-ray diffraction (XRD), Field-emission scanning electrochemical spectroscopy (FE-SEM) and electrochemical measurements. The effects of MWCNT concentration on the capacitance performance of MWCNT/NiCo<SUB>2</SUB>O<SUB>4</SUB> aerogels are studied. It is found that the NiCo<SUB>2</SUB>O<SUB>4</SUB>/MWCNT nanocomposite aerogels with MWCNTs∼2.1wt% reach the maximum specific capacitance of up to 1010Fg<SUP>−1</SUP> at a discharge current density of 0.1Ag<SUP>−1</SUP> with excellent cyclic stability. Further, these materials are applied for solid-state asymmetric supercapacitors and show higher areal capacitance value (471.8mFcm<SUP>−2</SUP>) at a current density of 5mAcm<SUP>−2</SUP> with good cycle stability and glowing red LED for 3mins. The superior electrochemical performance is due to the mesoporous structure and well-connected metal nanoparticles with MWCNT in the nanocomposite aerogels, which can provide more active sites to enhance the electrochemical performance of the device.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>