Solar energy is being investigated as a potential means to destroy environmental contaminants. In solar detoxification, photons in sunlight are used to break down contaminants into harmless or more easily treatable products. Solar detoxification is a "destructive" technology—it destroys contaminants as opposed to "transfer-of-phase" technologies such as activated carbon or air stripping, which are more commonly used to remove contaminants from the environment.

In a typical photocatalytic process, water or soil containing organic contaminants is exposed to sunlight in the presence of a catalyst such as titanium dioxide or humic and fulvic acids. The catalyst absorbs the high energy photons, and oxygen collects on the catalyst surface, resulting in the formation of reactive chemicals referred to as hydroxyl free-radicals and atomic oxygen (singlet oxygen). These reactive chemicals transform the organic contaminants into degradation products, such as carbon dioxide and water. Solar detoxification can be accomplished...