Self-assembled three-dimensional interpenetrating porous graphene aerogels with MnO2 coating and their application as high-performance supercapacitors
Abstract
In this work, a hybrid materials of MnO2-wrapped graphene aerogels (GAs) were prepared using a simple in situ reduction method. The porous GAs obtained in our work not only boost ion and electron movement in electrochemical processes but can also serve as a 3D skeleton for combining with MnO2, which allows the poor electronic conductivity of MnO2 nanoparticles to be wired up to a current collector through the underlying GA conducting layers. As a supercapacitor electrode material, the structure exhibits a high reversible capacity of 210 F g−1 at a current density of 0.5 A g−1 with an excellent cycling retention of 99% after the 800th cycle at a current density of 2 A g−1. These results highlight the importance of anchoring MnO2 on GAs for maximum utilization of the electrochemical activity and retaining the good electrochemical stability of the electrode materials.