METHOD FOR THE WET-CHEMICAL ETCHING OF TIO2 THIN-FILMS AND TIO2 PARTICLES AND ETCHING REAGENT

摘要

The invention relates to a method and an etching reagent for the wet-chemical etching of TiO2 thin-films and TiO2particles that permits a defined removal of the TiO2thin-film and a reduction of the particle size. The method comprises the steps: production of an etching reagent with a pH value greater than 13, said reagent containing a base with a concentration of 0.1 mol, selected from the bases NH4OH, NaOH, KOH or mixtures of the same and H2O2 with a smaller concentration than that of the base; setting of a temperature that is equal to or greater than the ambient temperature; immersion of the TiO2 thin-films and TiO2 particles in the etching reagent and steeping of the layers of the TiO2 thin-films and particles; said films and particles are then rinsed with distilled water and dried. To maintain the initial composition of the etching reagent, H2O2 is added during the etching process.