Premium
Strongly Coupled Pyridine‐V 2 O 5 · n H 2 O Nanowires with Intercalation Pseudocapacitance and Stabilized Layer for High Energy Sodium Ion Capacitors
Author(s) -
Dong Jun,
Jiang Yalong,
Wei Qiulong,
Tan Shuangshuang,
Xu Yanan,
Zhang Guobin,
Liao Xiaobin,
Yang Wei,
Li Qidong,
An Qinyou,
Mai Liqiang
Publication year - 2019
Publication title -
small
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.785
H-Index - 236
eISSN - 1613-6829
pISSN - 1613-6810
DOI - 10.1002/smll.201900379
Subject(s) - pseudocapacitance , materials science , intercalation (chemistry) , electrochemistry , nanowire , cathode , vanadium , pyridine , electrolyte , fourier transform infrared spectroscopy , chemical engineering , inorganic chemistry , nanotechnology , supercapacitor , chemistry , electrode , organic chemistry , engineering , metallurgy
Developing pseudocapacitive cathodes for sodium ion capacitors (SICs) is very significant for enhancing energy density of SICs. Vanadium oxides cathodes with pseudocapacitive behavior are able to offer high capacity. However, the capacity fading caused by the irreversible collapse of layer structure remains a major issue. Herein, based on the Acid–Base Proton theory, a strongly coupled layered pyridine‐V 2 O 5 · n H 2 O nanowires cathode is reported for highly efficient sodium ion storage. By density functional theory calculations, in situ X‐ray diffraction, and ex situ Fourier‐transform infrared spectroscopy, a strong interaction between protonated pyridine and VO group is confirmed and stable during cycling. The pyridine‐V 2 O 5 · n H 2 O nanowires deliver long‐term cyclability (over 3000 cycles), large pseudocapacitive behavior (78% capacitive contribution at 1 mV s −1 ) and outstanding rate capability. The assembled pyridine‐V 2 O 5 · n H 2 O//graphitic mesocarbon microbead SIC delivers high energy density of ≈96 Wh kg −1 (at 59 W kg −1 ) and power density of 14 kW kg −1 (at 37.5 Wh kg −1 ). The present work highlights the strategy of realizing strong interaction in the interlayer of V 2 O 5 · n H 2 O to enhance the electrochemical performance of vanadium oxides cathodes. The strategy could be extended for improving the electrochemical performance of other layered materials.