Polymer-derived N-doped carbon nanomaterials containing carbon nano-onions and their potential applicability

Abstract

Herein, we report the synthesis and characterization of materials consisting of carbon nano-onions (CNOs) and N and S atom-containing polymer precursors, readily available from polyacrylonitrile(PAN)–poly(acrylic esters) block copolymers. Two different acrylic esters were used, methyl and butyl acrylate carbon chains that formed a polymeric network with varying pore sizes on the CNO's surface. Their material counterparts without CNOs were also synthesized as reference materials. The polymers were annealed in airflow to stabilize PAN domains, followed by pyrolysis at 800 °C under an argon atmosphere. The N-rich carbon nanomaterials were loaded with S in the mixing–melting–diffusion process, resulting in S loading at 51–57 wt%. The synthesized N-doped carbon materials were used as positive electrodes in Li–S batteries. The battery with the CNO-based nanomaterial provided over 20% higher capacity than that without CNO. This suggests that designing and preparing N-doped carbon nanomaterials containing CNOs could be a promising direction in the search for cathode materials in Li–S batteries.