Thermally etched porous carbon cloth catalyzed by metal organic frameworks as sulfur hosts for lithium–sulfur batteries

Abstract

Activated carbon cloth (CC) plays vital roles in the fabrication of flexible energy devices, structured supports for catalysts, and CO2 capturer, etc. In terms of the conventional processing methods of activated CC, KOH and CO2 are the representative activation agents. Based on the idea of waiving the use of concentrated alkali and specialty gases, we demonstrate herein a highly efficient and previously unreported method of CC activation with a two-step procedure: homogeneous growth of metal organic frameworks (MOFs) on CC and subsequent activation catalyzed by the MOF derivatives. During pyrolysis, the MOF structures are transformed into Co3O4 particles, which react with carbon, leading to etching of the carbon fiber. This method can be used to form activated CC with coexistence of micropores, mesopores, and macropores. With the benefit of such hierarchical and unique structures, a free-standing sulfur-impregnated porous CC electrode demonstrates obvious advantages over CC-supported sulfur melt or sulfur slurry electrodes, which demonstrates great feasibility of MOF catalyzing porosification of CC for practical applications. This reported method not only broadens the scope of application of MOFs, it could also be further used to create hierarchical structures on other carbonaceous materials in various fields.