Experimental and theoretical study of ozone adsorption on alumina

Ozone adsorption has been studied by IR spectroscopy at low temperature. Although alumina is more acidic than TiO2, as shown by pyridine adsorption, IR spectroscopy did not detect O3 species adsorbed on strong Lewis Al3+ sites. However, O3 decomposition occurred and pyridine specific poisoning evidenced that such sites were involved in the decomposition. Quantum chemistry calculations confirmed such a result and specified that the remaining O(1D) resulting from the decomposition, in addition to physisorbed O2, was attached to the aluminum ion constituting the Lewis sites. The oxygen molecules would then gradually be desorbed.