Self-assembled carbon nanoribbons with the heteroatom doping used as ultrafast charging cathodes in zinc-ion hybrid supercapacitors
Yuying Li, Jiajia Huang, Liqun Kang, Zhihong Tian, Feili Lai, Dan J. L. Brett, Tianxi Liu, Guanjie He
Abstract
Abstract Zinc-ion hybrid supercapacitors (ZHSs) are highly desirable for large-scale energy storage applications owing to the merits of high safety, low cost and ultra-long cycle life. The poor rate performance of cathodes, however, severely hinders their application. Herein, aqueous ZHSs with superior performance were fabricated by employing a series of ultrathin carbon nanobelts modified with B, N, O (CPTHB- Bx ). The heteroatom doping can significantly modify the chemical behaviors of carbon frameworks, which could generate numerous active sites and accelerate the charge transport. The systematic investigation reveals that the B–N groups are active species for fast Zn-ion adsorption and desorption. As a result, the best-performed CPTHB-B2 exhibits an excellent electrochemical performance as cathodes in ZHSs, delivering a high specific capacitance of 415.3 F g −1 at 0.5 A g −1 , a record high capacitance retention of 81% when increasing the current densities from 0.5 to 100 A g −1 , an outstanding energy density of 131.9 W h kg −1 and an exceptionally high power density of 42.1 kW kg −1 . Our work provides a new cathode design for ultrafast charging Zn-ion storage devices.