Radical cations of aromatic molecules with high ionization potentials on the surfaces of oxide catalysts: Formation, properties, and reactivity

The results obtained by the authors on the formation and properties of the radical cations of benzene and other molecules with high ionization potentials on the surfaces of ZSM-5 zeolites and sulfated zirconium dioxide are analyzed in this paper. It was found that radical cations of aromatic compounds can be obtained both by a thermal process and under illumination with visible light. Radical cations were found to be key intermediates in the low-temperature polycondensation of aromatic compounds on these catalysts. A possible mechanism of the formation of radical cations and the nature of the sites responsible for these processes are discussed.