Synthetic Strategy for MnO₂ Nanoparticle/Carbon Aerogel Heterostructures for Improved Supercapacitor Performance

Constructing heterostructure in nanomaterials is a scientific and efficient method to optimize the electrochemical properties of supercapacitors. Carbon aerogels (CAs) can enhance electrical conductivity and ion diffusion because of their three-dimensional porous structure, which is useful for fabricating electrodes. The moderate nanoheterostructures in aerogel nanomaterials have made great contributions to the optimization of application performance. Herein, a simple method for constructing the MnO₂ nanoparticle/CA (MnO₂/CA) heterostructure is proposed. The MnO₂/CA heterostructure exhibits outstanding electrochemical capability in a three-electrode system, with a specific capacitance of 384 F/g, higher than 201 F/g of the CA, at a current density of 0.5 A/g. When MnO₂/CA is used as a symmetric supercapacitor, it also exhibits a high energy density and power density, with the highest energy density of 33.78 Wh/kg. The prepared MnO₂/CA shows improved performance for synergies in providing a high specific capacity and long cycle life.