State-of-the-art, challenges and prospects of heterogeneous tandem photocatalysis

With numerous chemical reactions involved, photocatalysis has gained a lot of attention in recent decades as a possible method for converting solar energy to value-added chemicals. The effectiveness of photocatalytic systems has been increased through the development of several methods and strategies. However, because of their poor performance and the low utility value of certain reaction products, their practical uses are quite constrained. Tandem photocatalysis has gained popularity recently as a result of its extremely selective transformations, exceptional performance, and ability to produce highly valuable compounds from its byproducts. This review summarizes the latest applications of heterogeneous tandem photocatalysis in the evolution of hydrogen, reduction of CO₂, and reduction of nitrates in aqueous media. It also looks into the literature on the utilization of tandem reactions in the in-situ synthesis of useful and environmentally friendly materials sequel to previous reduction reactions.