Visible Light Photocatalysis in Water

The present chapter aims at introducing the main approaches to developing photocatalytic synthetic methods by using water as a reaction medium. By merging the innate green properties of water with the exploitation of a renewable energy source, such as light, this field of research represents one of the most intensive ones. A selection of the literature available so far is divided into three main sections based on (i) the water solubility of the photocatalyst and the use of additives including surfactants (photomicellar catalysis); (ii) the exploitation of on-water conditions to achieve acceleration of reaction rates; (iii) photobiocatalytic methods. The latter, indeed, are intrinsically designed and optimized to be performed in an aqueous environment. Taken together, all the reactions herein highlighted offer unique synthetic opportunities to address the main challenge of a sustainable manufacturing of chemicals.