Charging a Negatively Curved Nanographene and Its Covalent Network
Yiqun Zhang, Yikun Zhu, Danni Lan, Sai Ho Pun, Zheng Zhou, Zheng Wei, Ying Wang, Hung Kay Lee, Chao Lin, Jiangpeng Wang, Marina A. Petrukhina, Quan Li, Qian Miao
Abstract
This study explores a bottom-up approach toward negatively curved carbon allotropes from octabenzo[8]circulene, a negatively curved nanographene. Stepwise chemical reduction reactions of octabenzo[8]circulene with alkali metals lead to a unique highly reduced hydrocarbon pentaanion, which is revealed by X-ray crystallography suggesting a local view for the reduction and alkali metal intercalation processes of negatively curved carbon allotropes. Polymerization of the tetrabromo derivative of octabenzo[8]circulene by the nickel-mediated Yamamoto coupling reaction results in a new type of porous carbon-rich material, which consists of a covalent network of negatively curved nanographenes. It has a specific surface area of 732 m2 g–1 and functions as anode material for lithium ion batteries exhibiting a maximum capacity of 830 mAh·g–1 at a current density of 100 mA·g–1. These results indicate that this covalent network presents the key structural and functional features of negatively curved carbon allotropes.