Photocatalyst containing metallic ultrafine particles and process for producing said photocatalyst

摘要

There is disclosed a photocatalyst which comprises a substrate having a photocatalytic function and metallic nanocolloid particles that are supported on the substrate by the use of a metallic nanocolloid liquid substantially free from a protective colloid formation agent. A highly active photocatalyst containing metallic ultrafine particles is provided by bringing a substrate such as fine particles having a photocatalytic function into contact with a metallic nanocolloid liquid which is substantially free from a protective colloid formation agent, and which has favorable dispersion stability even if containing metallic nanocolloid particles in a relatively high concentration. Accordingly the photocatalyst containing metallic ultrafine particles can be produced at a low cost without being restricted on the place of production.