Effect of structural variation in biomass-derived nonfluorinated ionic liquids electrolytes on the performance of supercapacitors  

作　　者：Inayat Ali Khan Yong-Lei Wang Faiz Ullah Shah 

机构地区：[1]Chemistry of Interfaces.Lulea University of Technology.SE-97187 Luled,Sweden [2]Department of Materials and Environmental Chemistry.Arrhenius Laboratory.Stockholm University.SE-10691Stockholm.Sweden

出　　处：《Journal of Energy Chemistry》2022年第6期174-184,I0005,共12页能源化学（英文版）

基　　金：the financial support in the form of a stipend for IAK (grant number: SMK-1838);The financial support from the Swedish Research Council (project number: 201804133) is gratefully acknowledged for supporting this work;NSC partially funded by Swedish Research Council through grant agreement no. 2016-07213。

摘　　要：There is a growing interest in sustainable and high performance supercapacitors(SCs) operating at elevated temperatures as they are highly demanded in heat-durable electronics. Here, we present a biomass-derived nonfluorinated ionic liquid(IL) [P_(4444)][HFuA] and its structural analogue [P_(4444)][TpA]as electrolytes for supercapacitors comprising multiwall carbon nanotubes and activated charcoal(MWCNTs/AC) mixed carbon composite electrodes. A detailed investigation of the effect of scan rate, temperature, potential window and orientation of ions on the electrodes surfaces is performed. The supercapacitors exhibited relatively lower specific capacitance for both [P_(4444)][HFuA] and [P_(4444)][TpA] ILs at room temperature. However, the specific capacitance has significantly increased with an increase in temperature and potential window. The equivalent serie resistances of the SCs is deceased with increasing temperatures, which is a result of improved ionic conductivities of the IL electrolytes. In CV cycling at60 °C, the capacitor with [P_(4444)][HFuA] IL-based electrolyte retained about 90% of its initial capacitance,while the capacitor with [P_(4444)][TpA] IL-based electrolyte retained about 83% of its initial capacitance.Atomistic computations revealed that the aromatic [FuA]^(-) and [TpA]^(-) anions displayed perpendicular distribution that can effectively neutralize charges on the carbon surfaces. However, the [HFuA]-anion exhibited somewhat tilted configurations on the carbon electrode surfaces, contributing to their outstanding capacitive performance in electrochemical devices.

关 键 词：BIOMASS Ionic liquids Carbon electrodes SUPERCAPACITORS Molecular dynamic simulations 

分 类 号：TM53[电气工程—电器] O645.1[理学—物理化学] O646[理学—化学]