Enhancing the capacitive performance of microporous materials with protic ionic liquids

Gallegos, Alejandro; Wu, Jianzhong

doi:10.1016/j.molliq.2022.120161

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Enhancing the capacitive performance of microporous materials with protic ionic liquids

Gallegos, Alejandro·Wu, Jianzhong

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Abstract

Classical density functional theory (cDFT) is used to investigate the electrosorption of protic ionic liquids in porous electrodes within the framework of a coarse-grained model. The purpose of this study is to clarify the capacitive behavior of protic ionic liquids in confined geometry. Previous studies have indicated that thermodynamic properties (e.g., capacitance, phase behavior and ionic conductivity) are influenced by the composition of the acid-base system and show asymmetry between acid dominant versus base dominant compositions. Here, we find that the electric double layer capacitance can be significantly improved by using protic ionic liquids compared to its aprotic counterpart through optimization of the mixture composition (i.e., the ratio of acid to base). We demonstrate the influence of pore size and applied voltage on the capacitance performance of protic ionic liquids and provide insight into microscopic understanding of ion and solvent distributions inside micropores.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY Chemistry Classical density functional theory Physics Protic ionic liquids Supercapacitors

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Gallegos, Alejandro, Wu, Jianzhong. 2022-08-24. Enhancing the capacitive performance of microporous materials with protic ionic liquids. https://doi.org/10.1016/j.molliq.2022.120161

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