Reactions of water-stable C60 clusters (nC60) in water with OH radicals (•OH) and hydrated electrons (eaq -), generated by steady-state γ-radiation, were observed and characterized. Ordered C60 clusters were relatively recalcitrant to highly reactive •OH and eaq- species, with only a fraction of carbons oxidized and reduced, respectively. Pulse radiolysis suggested that the reactions of nC60 with OH• and e aq- were diffusion limited, with rate constants of (7.34 ± 0.31) - 109 M-1 s-1 and (2.34 ± 0.02) - 1010 M-1 s-1, respectively. Quantum mechanical calculations of binding energy of the C60-OH adduct as a function of C60 clustering degree indicate, despite an initial fast reaction, a slower overall conversion due to thermodynamic instability of C 60-OH intermediates. The results imply that ordered clustering of C60 in the aqueous phase significantly hinders C60s fundamental reactivity with radical species.
ASJC Scopus subject areas
- Environmental Chemistry