Interaction of imidazolium based ionic liquid electrolytes with carbon nitride electrodes in supercapacitors; a step forward for understanding electrode-electrolyte interaction

Ionic liquids (ILs) are considered as an emerging class of electrolytes finding their applications in energy storage devices due to wide electrochemical windows, nonflammability, low volatility, and high thermal and chemical stability. The interaction of three ionic liquids i.e., 1,3-dimethylimidazolium chloride (MIC), 1,3-disulfonic acid imidazolium nitrate (DIN), 1-Ethyl-3-methylimidazolium tetrafluoroborate (EMI) with C2N surface is evaluated for better understanding electrode-electrolyte interaction in supercapac-itors. The interaction of electrolytes on C2N electrode is studied through interaction energy analysis, non -covalent interactions (NCI) analysis and quantum theory of atoms in molecule (QTAIM) analyses. Electronic properties are investigated through natural bond orbital (NBO), frontier molecular orbital (FMOs), density of states and electron density analyses. Interaction energies calculated for the most stable geometry of the studied electrolytes are-13.83 kcal/mol (DIN@C2N),-25.90 kcal/mol (EMI@C2N), and-26.94 kcal/mol (MIC@C2N). NBO analysis reveals that an appreciable amount of charge is transferred from surface to ionic liquids, and these results are further supported by EDD analysis. Moreover, FMO analysis unveils that 2.04 eV decrease in energy gap of MIC@C2N complex. We strongly believe that this study provides a deep insight in better understanding the electrode-electrolyte interac-tions, which play vital role in various application such as super-capacitors, batteries, and fuel cells.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

Ionic liquids (ILs) are a promising class of electrolytes for energy storage devices due to their favorable properties. This study investigates the interaction of three ILs with a C2N surface to gain insight into the electrode-electrolyte interaction in supercapacitors. Through various analyses, the researchers examine the energy and electronic properties of the ILs on the C2N electrode. The results provide valuable information for understanding and optimizing the electrode-electrolyte interactions in applications such as supercapacitors, batteries, and fuel cells.