TY  - JOUR
A1  - Yan, Runyu
A1  - Josef, Elinor
A1  - Huang, Haijian
A1  - Leus, Karen
A1  - Niederberger, Markus
A1  - Hofmann, Jan P.
A1  - Walczak, Ralf
A1  - Antonietti, Markus
A1  - Oschatz, Martin
T1  - Understanding the charge storage mechanism to achieve high capacity and fast ion storage in sodium-ion capacitor anodes by using electrospun nitrogen-doped carbon fibers
JF  - Advanced functional materials
N2  - Microporous nitrogen-rich carbon fibers (HAT-CNFs) are produced by electrospinning a mixture of hexaazatriphenylene-hexacarbonitrile (HAT-CN) and polyvinylpyrrolidone and subsequent thermal condensation. Bonding motives, electronic structure, content of nitrogen heteroatoms, porosity, and degree of carbon stacking can be controlled by the condensation temperature due to the use of the HAT-CN with predefined nitrogen binding motives. The HAT-CNFs show remarkable reversible capacities (395 mAh g(-1) at 0.1 A g(-1)) and rate capabilities (106 mAh g(-1) at 10 A g(-1)) as an anode material for sodium storage, resulting from the abundant heteroatoms, enhanced electrical conductivity, and rapid charge carrier transport in the nanoporous structure of the 1D fibers. HAT-CNFs also serve as a series of model compounds for the investigation of the contribution of sodium storage by intercalation and reversible binding on nitrogen sites at different rates. There is an increasing contribution of intercalation to the charge storage with increasing condensation temperature which becomes less active at high rates. A hybrid sodium-ion capacitor full cell combining HAT-CNF as the anode and salt-templated porous carbon as the cathode provides remarkable performance in the voltage range of 0.5-4.0 V (95 Wh kg(-1) at 0.19 kW kg(-1) and 18 Wh kg(-1) at 13 kW kg(-1)).
KW  - carbon fibers
KW  - nitrogen-doped carbon
KW  - sodium-ion capacitors
KW  - sodium storage mechanism
Y1  - 2019
U6  - https://doi.org/10.1002/adfm.201902858
SN  - 1616-301X
SN  - 1616-3028
VL  - 29
IS  - 26
PB  - Wiley-VCH
CY  - Weinheim
ER  -