A multiple coating route to hollow carbon spheres with foam-like shells and their applications in supercapacitor and confined catalysis

Abstract

Recent advances in the sol–gel process derived resorcinol-formaldehyde (RF) coating strategies offer new opportunities for the synthesis and applications of hollow carbon spheres (HCS). Due to the lack of an effective route for controlling the pore structures, the synthesis of RF resin derived HCS with a high specific surface area for promising applications is still a challenge. In this work, we present a facile and effective template-directed multiple coating route to synthesize RF resin derived HCS with foam-like shells (HCSF). The as-synthesized HCSF exhibit a significantly higher specific surface area (1286 m² g⁻¹) and larger pore volumes (2.25 cm³ g⁻¹) than the RF resin derived HCS (639 m² g⁻¹ and 0.56 cm³ g⁻¹). Our experiments demonstrated that the cationic surfactant CTAB plays a critical role in forming the foam-like pore structure. Compared with the RF resin derived HCS, the as-synthesized HCSF show advantageous performances in supercapacitor and confined catalysis due to their unique pore structures.