Pomegranate-like C60@cobalt/nitrogen-codoped porous carbon for high-performance oxygen reduction reaction and lithium-sulfur battery
Jianhua Wu, Shiyang Wang, Zhanwu Lei, Runnan Guan, Muqing Chen, Pingwu Du, Yalin Lu, Ruiguo Cao, Shangfeng Yang
Abstract
Porous carbon materials play essential roles in electrocatalysis and electrochemical energy storage. It is of significant importance to rationally design and tune their porous structure and active sites for achieving high electrochemical activity and stability. Herein, we develop a novel approach to tune the morphology of porous carbon materials (PCM) by embedding fullerene C60, achieving improved performance of oxygen reduction reaction (ORR) and lithium-sulfur (Li-S) battery. Owing to the strong interaction between C60 and imidazole moieties, pomegranate-like hybrid of C60-embedded zeolitic imidazolate framework (ZIF-67) precursor is synthesized, which is further pyrolyzed to form C60-embedded cobalt/nitrogen-codoped porous carbon materials (abbreviated as C60@Co-N-PCM). Remarkably, the unique structure of C60@Co-N-PCM offers excellent ORR electrocatalytic activity and stability in alkaline solutions, outperforming the commercial Pt/C (20 wt.%) catalyst. Besides, C60@Co-N-PCM as a novel cathode delivers a high specific capacity of ∼ 900 mAh·g−1 at 0.2 C rate in Li-S batteries, which is superior to the pristine ZIF-67-derived PCM without embedding C60.