Abstract
One of the basic tenets of photochemistry is that the driving force in a photochemical reaction is the quantized but very large energy of the photon. This means that even an extremely weak source of excitation light would give rise to a non-zero reaction rate. Let us consider the UV light existing in an indoor living environment. Its amount is very small, but each photon possesses an extremely large energy. If we have a system which could collect this weak UV light efficiently and then use it to drive photochemical reactions, most organic compounds could be burned in air at room temperature. This idea can be approached via TiO2 film photocatalysis in a reaction with an extremely low reactant concentration. One of the motivations for a study under such conditions is the desire to develop methods of purifying interior living and working environments using ambient light. The present report deals with the discovery that materials coated with photoactive TiO2 exhibit deodorizing, sterilizing and self-cleaning functions photochemically under ordinary room light illumination without using any reactive chemicals.
