A method for in-situ formation of surface modified mixed oxide material includes burning a titanium chloride comprising compound and a silicon chloride comprising compound in the presence of oxygen and hydrogen in a reactor to form a plurality of silica-titania mixed oxide particles, wherein a temperature during the burning step is from 700 to 1100.degree. C. In embodiments of the invention a concentration of hydrogen is in a stoichiometric excess (H.sub.2:O.sub.2) to oxygen from 2.02:1 to 2.61:1 during the burning step. While the mixed oxide particles are still in the reactor, a metal is deposited on a surface of the mixed oxide particles at a temperature below the temperature of the burning step, such as in the form of randomly located nanoparticle clusters which only partially cover the surface of the mixed oxide particles. The titania can be non-stoichiometric TiO.sub.2-x, wherein 0.1