Selective photocatalytic and photoelectrocatalytic synthesis of valuable compounds in aqueous medium

In the past decades, photocatalytic and photoelectrocatalytic methods have been widely employed for the degradation of harmful compounds present both is gaseous and aqueous effluents. In the last years scientists have paid great attention to the synthesis of valuable compounds and hydrogen production. Organic syntheses are generally carried out in organic solvents, under high temperature/pressure, with toxic oxidants such as permanganate. On the other hand, photocatalysis and photoelectrocatalysis using water as solvent, air or water as oxidant, and sunlight as energy source, can be an efficient alternative to the traditional, non-environmentally friendly methods. This review summarizes the photocatalytic and photoelectrocatalytic transformations of organic molecules to commercially valuable products in water, sometimes evaluating also the contemporary H2 production. The reaction conditions, mechanisms and kinetics are presented and discussed. Future perspectives are also given.