▎ 摘　　要

NOVELTY - A photocatalyzer is manufactured by forming photocatalyst secondary particle having particle size of 2-2000 mu m by aggregating photocatalyst primary particle with particle size of 4-100 nm and inorganic binder, immobilizing photocatalyst secondary particle on base material, covering the base-material surface with solution containing inorganic binder and photocatalyst secondary particle, and heating at 80-350 degrees C. USE - Manufacture of photocatalyzer (claimed) used for purifying water and organic substance and for hydrogen production. ADVANTAGE - The photocatalyzer can advance the photocatalytic reaction efficiently and has high photocatalytic activity. Stripping of photocatalyst secondary particle by generation of bubble in aqueous solution from base material is suppressed. The photocatalyzer can advance the oxidative degradation of hydrogen manufacture in sacrificial agent aqueous solution and organic substance in aqueous solution. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a photocatalyzer comprising photocatalyst secondary particle with particle size of 2-2000 mu m formed by aggregating photocatalyst primary particle with particle size of 4-100 nm and inorganic binder where photocatalyst secondary particle is immobilized on surface of base material, and solution which contains inorganic binder and photocatalyst secondary particle and covers the surface of base material that is heated at 80-350 degrees C.