Theoretical Study of Benzoquinone Derivatives as Organic Cathode Materials in Lithium-Ion Batteries

In lithium-ion batteries (LIBs), electrode materials are important because of their energy density and long cycle life. Currently, the use of green energy electrodes is preferable to the use of traditional inorganic electrode materials. These compounds are sustainable and renewable and can be obtained from natural products. Benzoquinone derivatives have been proven to be useful organic cathodes; therefore, their effects can be altered through structural changes as well as the introduction of functional groups. In this research, the electronic structures of some benzoquinone derivatives and their interactions with Li atoms were studied via density functional theory (DFT) calculations via Gaussian ۰۹ at B۳LYP/۶-۳۱۱G*. The effects of the position and type of various substituents on the charge density of the oxygen atom in carbonyls were compared via nuclear quadrupole coupling constant (NQCC) calculations. The results showed that the charge density of the carbonyl oxygen atoms in the benzoquinone derivatives changed with changing substitutions. In the presence of substituents such as -OCH۳, -Cl, and -CN, the calculated ۱۷O-NQCCs are reduced by approximately ۵۰۰ kHz. NBO analysis revealed that some interactions in perfluoroalkylated BQs cause a decrease in the electron density of the oxygen atoms in the carbonyl group. An investigation of the orbital energies of selected MOs of the radical intermediates of BQ derivatives confirmed the relationship between the stability of the radical intermediate and the charge‒discharge cycle performance.

کلیدواژه ها:

Li-ion batteries ، benzoquinone ، Charge density ، DFT ، organic cathode