Facile dip coating processed graphene/MnO2 nanostructured sponges as high performance supercapacitor electrodes

► A facile and fast dip coating process has been developed to fabricate graphene/MnO2 nanostructured sponge electrodes. ► The control of the morphology, size, and uniformity of graphene/MnO2 based composite materials as well as facile and large scale processing are simultaneously achieved. ► Choose commercial sponges as skeletons to construct homogeneous three-dimensional interconnected macro-network RGO composite.