Ultrafine design of carbon whisker array @ hollow carbon sphere anode for superior K-storage

• Published in: Applied surface science 2024-03, Vol.649, p.159113, Article 159113
• Main Authors: Pang, Yinshuang, Lai, Qingxue, Chen, Ningning, Shen, Nailu, Chen, Hong, Zhang, Wanying, Liu, Zhi, Nie, Luanjie, Zheng, Jing
• Format: Article
• Language: English
• Subjects: 3D array structure; Bottom-up strategy; Hollow structure; K-storage mechanism; Nanocarbon materials
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2023.159113

[Display omitted] •A C–C coupling-based strategy was proposed to achieve multidimensional manipulation over nanocarbon K-storage anode.•The optimized CWA@HCS material delivered superior K-storage performance to most previously reported carbon-based materials.•The surface capacitive-dominated K-storage mechanism ensures superior K storage performance. Even though bottom-up strategy has been successfully developed to construct nanocarbon materials from molecule blocks for energy storage applications, elaborate structure manipulation via a facile and scalable method remains a big challenge. Herein, a facile free-radical C–C coupling-based bottom-up strategy was proposed to controllably construct carbon whisker array @ hollow carbon sphere (CWA@HCS) anode from the molecule block of hexabromobenzene (HBB) for superior K-storage. The novel CWA@HCS anode was easily achieved via the controllable catalysis of C–C coupling reaction on the surface of commercial metallic Cu particles. The optimized CWA@HCS anode delivered a high reversible K-storage capacity of 367.6 mAh/g at 50 mA/g, excellent rate capability (155.5 mAh/g at 1000 mA/g), and excellent long-term cycle performance (182.5 mAh/g maintained after 700 cycles at 500 mA/g). In addition, the full cell assembled from CWA@HCS electrode showed excellent cycle performance and rate performance. These excellent K-storage properties should be attributed to the surface capacitive-dominated K-storage mechanism guaranteed by the three-dimensional (3D) array structure. This study provides a basic reference for the design of advanced nanocarbon materials as well as anode materials for potassium ion batteries.