One-step synthesis of robust carbon nanotube foams with ultrahigh surface area for high-performance lithium ion battery

A novel three-dimensional（3D） carbon nanotube foams（CNTF） with ultrahigh specific surface area have been fabricated through a unique but facile one-step synthesis by using CO2 as both carbon source and activating agent. The activation temperature and time have been adjusted, and the best sample demonstrates a specific surface area of 1959.8 m2 g–1 and a total pore volume of 3.23 cm3 g–1. A reversible capacity of about 870 mAhg–1 is maintained at 50 mAg–1 when the CNTF used as cathode materials. Meanwhile, the capacity is as large as 320 mAhg–1 at the current density of 2 A g–1 and the capacity retention is nearly 100% after 500 cycles. These excellent and highly stable battery performances should be attributed to the structural advantages of as-synthesized CNTFs generated by using a facile CO2-assisted strategy, which may potentially be applied in large scale production of porous 3D carbon materials in the fields of energy storage and conversion.