Highly nitrogen doped carbon nanofibers with superior rate capability and cyclability for potassium ion batteries.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29712922.
- Also identified by DOI 10.1038/s41467-018-04190-z and PMC identifier 5928078.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Potassium-ion batteries are a promising alternative to lithium-ion batteries. However, it is challenging to achieve fast charging/discharging and long cycle life with the current electrode materials because of the sluggish potassiation kinetics. Here we report a soft carbon anode, namely highly nitrogen-doped carbon nanofibers, with superior rate capability and cyclability. The anode delivers reversible capacities of 248 mAh g<sup>-1</sup> at 25 mA g<sup>-1</sup> and 101 mAh g<sup>-1</sup> at 20 A g<sup>-1</sup>, and retains 146 mAh g<sup>-1</sup> at 2 A g<sup>-1</sup> after 4000 cycles. Surface-dominated K-storage is verified by quantitative kinetics analysis and theoretical investigation. A full cell coupling the anode and Prussian blue cathode delivers a reversible capacity of 195 mAh g<sup>-1</sup> at 0.2 A g<sup>-1</sup>. Considering the cost-effectiveness and material sustainability, our work may shed some light on searching for K-storage materials with high performance.