In chemistry, photocatalysis is the acceleration of a photoreaction in the presence of a catalyst. In catalysed photolysis, light is absorbed by an adsorbed substrate. In photogenerated catalysis, the photocatalytic activity (PCA) depends on the ability of the catalyst to create electron–hole pairs, which generate free radicals (hydroxyl radicals: ·OH) able to undergo secondary reactions. Commercial application of the process is called Advanced Oxidation Process (AOP).
Chlorophyll of plants is a type of photocatalyst. Photocatalysis compared to photosynthesis, in which chlorophyll captures sunlight to turn water and carbon dioxide into oxygen and glucose, photocatalysis creates strong oxidation agent to breakdown any organic matter to carbon dioxide and water in the presence of photocatalyst, light and water.
