Large-scale synthesis of highly structural-connecting carbon nanospheres as an anodes material for lithium-ion batteries with high-rate capacity

• Published in: Chemical engineering journal advances 2020-10, Vol.2, p.100014, Article 100014
• Main Authors: Peng, Chuan, Liao, Ming Dong, Lv, Xue Lin, Chen, Lin, Hou, Sheng Ping, Min, Dan, Chen, Jian, Wang, Hao-Lun, Lin, Jarrn-Horng
• Format: Article
• Language: English
• Subjects: High-rate capacity; Highly structural-connecting carbon nanospheres; Large-scale synthesis; Lithium-ion batteries
• ISSN: 2666-8211; 2666-8211
• DOI: 10.1016/j.ceja.2020.100014

•A facile method has been suggested to fabricate highly structural-connecting carbon nanospheres (CNSs).•This method is simple and easily to scale-up extensively.•HNO3-treated CNSs demonstrate admirably electrochemical performance as the anode materials for lithium-ion batteries.•HNO3-treated CNSs display a capacity of 420 mAh g−1 at 0.2 A g−1 and exists excellent rate capacity of 280 mAh g−1 at 2 A g−1. Highly structural-connecting carbon nanospheres (CNSs) are prepared using thermal pyrolysis of acetylene at 580 °C with a yield of 1 kg h−1. The as-prepared CNSs present a particle-size distribution in a range of 60–90 nm, and display a highly-connected structure (the specific oil-adsorption value is 180 mL/100g according to the ASTM D2415-19 method) with a specific surface area of 30 m2 g−1. The as-prepared CNSs were treated with an acid purification (1M HNO3 80 °C for 2 h) or thermal treatments at higher temperatures (800 or 1000 °C for 2 h) under argon atmosphere. The CNSs-based samples demonstrate admirably electrochemical performance as the anode materials for lithium-ion batteries (LIBs). Additionally, HNO3-treated CNSs display better performances in LIBs comparing with pristine, thermal-treated CNSs, graphite, and carbon black-super-P and acetylene black. For the HNO3-CNSs sample, the first charge-discharge cycle of the specific charge capacity is 506 mAh g−1, and which maintains at 420 mAh g−1 of specific discharge capacity, the initial coulombic efficiency is 85.0%. Moreover, the rate capacity is conducted at various current densities from 0.05 to 2 A g−1, the capacitance retention rate can maintain above 98 % after 100 cycles. Remarkably, the HNO3-treated CNSs exists excellent rate capacity of 280 mAh g−1 at 2 A g−1, which is superior to those of previously reported CNSs. Herein, we provide a facile route to massively prepare a high-performance anode material for LIBs. [Display omitted] Nitrogen-doped activated carbon nanofibers (N-ACF) demonstrates excellent electrochemical performance with a specific capacitance value of 227 F g−1 at 0.5 A g−1, and shows a 94 % capacitance retention after 10000 cycles at 2 A g−1. Moreover, N-ACF-based electrode displays a high energy-density of 14.30 Wh kg−1 and a high power-density of 79.88 W kg−1 in 1 M Na2SO4 electrolyte.