Electrocatalysis of molecular oxygen reduction reaction at liquid-liquid interface and DFT computational study of proton transfer from the conjugate acid of 2,2′-dipyridylamineto oxygen

• Published in: Journal of molecular modeling 2020-12, Vol.26 (12), p.350-350, Article 350
• Main Author: Soleymani-Bonoti, Fatemeh
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Molecular Medicine; Original Paper; Theoretical and Computational Chemistry
• ISSN: 1610-2940; 0948-5023
• DOI: 10.1007/s00894-020-04605-z

In this study, the catalytic effect of 2,2′-dipyridylamine (DPA) on the reduction of oxygen (O 2 ) at the polarized water/1,2-dichloroethane (DCE) interface was investigated. Ferrocene (Fc) and tetrathiafulvalene (TTF) were weak electron donors used in this study. Slow reduction of O 2 at the interface containing Fc and TTF was significantly accelerated upon the addition of DPA. Voltammetry and biphasic shake flask experiments revealed that DPA acts as a proton ionophore to transfer protons between the aqueous and organic phases. The PA, GB, and pK a values of all possible conjugate acids of DPA were calculated. Then, a mechanism was suggested to explain the interaction between protonated DPA and oxygen molecular. The mechanism was computationally analyzed by using density functional theory (DFT). Furthermore, DFT calculations at the B3LYP/6-31G** level of theory showed that the conjugate acid species of DPA transfer proton to O 2 at the interface. The results show that DPA-H 2+ and DPA-H 1+ are the best species to transfer proton to molecular oxygen.