TY  - JOUR
A1  - Quan, Ting
A1  - Haerk, Eneli
A1  - Xu, Yaolin
A1  - Ahmet, Ibbi
A1  - Höhn, Christian
A1  - Mei, Shilin
A1  - Lu, Yan
T1  - Unveiling the formation of solid electrolyte interphase and its temperature dependence in "Water-in-Salt" supercapacitors
JF  - ACS applied materials & interfaces
N2  - "Water-in-salt" (WIS) electrolytes have emerged as an excellent superconcentrated ionic medium for high-power energy storage systems such as supercapacitors due to their extended working potential compared to the conventional dilute aqueous electrolyte. In this work, we have investigated the performance of WIS supercapacitors using hollow carbon nanoplates as electrodes and compared it to that based on the conventional "salt-in-water" electrolytes. Moreover, the potentiostatic electrochemical impedance spectroscopy has been employed to provide an insightful look into the charge transport properties, which also, for the first time, reveals the formation of a solid-electrolyte interphase (SEI and their temperature-dependent impedance for charge transfer and adsorption. Furthermore, the effect of temperature on the electrochemical performance of the WIS supercapacitors in the temperature range from 15 to 60 degrees C has been studied, which presents a gravimetric capacitance of 128 F g(-1) and a volumetric capacitance of 197.12 F cm(-3) at 55 degrees C compared to 87.5 F g(-1) and 134.75 F cm(-3) at 15 degrees C. The in-depth understanding about the formation of SEI layer and the electrochemical performance at different temperatures for WIS supercapacitors will assist the efforts toward designing better aqueous electrolytes for supercapacitors.
KW  - "water-in-salt"
KW  - supercapacitor
KW  - solid electrolyte interphase
KW  - electrochemical impedance spectroscopy
KW  - temperature effect
Y1  - 2021
U6  - https://doi.org/10.1021/acsami.0c19506
SN  - 1944-8244
SN  - 1944-8252
VL  - 13
IS  - 3
SP  - 3979
EP  - 3990
PB  - American Chemical Society
CY  - Washington
ER  -