N-Doped Mesoporous Carbon Sheets/Hollow Carbon Spheres Composite for Supercapacitors.

Composite carbon materials with multiple morphologies (such as spheres/sheets and spheres/tubes) that combine the merits of both structures have a wide range of applications in electrochemistry, catalysis, energy storage, and so on. Therefore, the development of an efficient and simple method for preparing carbonaceous composite materials is a research hot spot. On the basis of the inhomogeneity of 3-aminophenol/formaldehyde (3-AF) polymerization spheres, the hollow 3-AF spheres were obtained after the dissolution of the internal 3-AF oligomer. The dispersed 3-AF oligomer was reassembled with silicate oligomers on the hard template of Mg(OH)2 sheets and hollow 3-AF spheres linked by CTAB through electrostatic force. The obtained N-MCS/HCS possessed both sheet and sphere structure, with a high specific surface area and uniform mesoporous distribution. As an electrode material, N-MCS/HCS exhibited a good specific capacity (270 F g-1 at the current density of 1 A g-1) and outstanding cycling life stability (96.3% after 5000 cycles) at a current density of 5 A g-1 and could be used as a new electrode material.