provides an in-depth treatment of the subject by exploring the fundamentals required for the selection of the materials, their synthesis methods, and possible ways to modify them for higher efficiency and enhanced stability. The prospects of adopting these sustainable solutions at a commercial level are summarized. Special emphasis is given to the figure-of-merits for currently developed systems for hydrogen generation and CO2 reduction and to an assessment of available materials in terms of efficacy and efficiency. also includes information on: is a highly useful guide for both novice and experienced researchers involved in renewable energy and carbon dioxide utilization that explains the current state of the field and discusses future perspectives.