Rich porous dual-shell carbon spheres by dissolution-reassembly with high performance in supercapacitor

Abstract

Dual-shell hollow carbon spheres (DHCS) is beneficial for charge transfer and storage due to their regular spherical morphology, large cavity, rich porous structure and thin dual-shell, which guarantees the improved electrochemical performance. Herein, a dissolution-reassembly strategy with silica additive is used to prepare DHCS with excellent electrochemical performance in supercapacitor. The core of solid aminophenol/formaldehyde (AF) resin spheres is coated by compact silica shell. AF core can be selectively dissolved by appropriate amounts of acetone to create cavity. Moreover, the dissolved AF oligomer will re-assembly with silica additive on the surface of compact silica shell to from another shell under the bridge effect of cetyltrimethyl-ammonium bromide. After the pyrolysis and etching silica, the DHCS was obtained, showing uniform spherical morphology, thin dual-shell, rich porous structure, high surface area and possesses suitable N-doping content, which endows the DHCS with outstand electrochemical performance when used as electrode material in supercapacitor.