Photoinduced CO-Reduction in Aqueous Suspension of n-TiO2

TiO2-suspension as well as ΤiΟ2-colloide in aqueous solutions are acting as catalyst for trans­forming CO into formaldehyde under illumination with uv-light. The yield of formaldehyde was studied as a function of pH (range: 1-7) and of the n-TiO2 content in the suspension at pH 2. Probable reaction mechanisms are presented.