Hydrogen peroxide was adsorbed from an aqueous solution by titanium (IV) oxide grafted on a silica gel surface, The maximum sorption capacity, 1.2 molecule nm(-2), was achieved in solution at pH 3. The photoacoustic spectrum of the sorbed species indicated a similar structure for the complex formed between Ti4+ and H2O2 in aqueous solution (Ti(H2O2)(m)(4+)). The adsorbed hydrogen peroxide retained the oxidation capacity for several weeks, Electron spin resonance showed the presence of a free radical on the surface, The observed g values, g(1) = 2.000, g(2) = 2.007, and g(3) = 2.020, were attributed to the = Ti+O2- radical, formed during the decomposition of adsorbed hydrogen peroxide.