Potential Methods and Perspectives of Solar Energy Conversion via Photocatalytic Processes

World annual consumption of energy is now about 5 × 1016 kcal and doubles every 15 to 20 years [1–4]. The main contribution to the energy balance of mankind is made by organic fossil fuels. However, if one compres modern annual energy consumption with the estimated energy that can be produced by burning all the prospected fossil fuels of the Earth (about 1019 kcal [1, 6]), the search for novel sources indeed becomes urgent, For the long-term prospects there are two most promising novel resources: thermonuclear energy baaed on dieterium and solar energy [1–13]. At present, wide use of these sources is not possible. It should be noted, however, that while controlled thermonuclear synthesis is in a state of experimental study, solar energy is continuously received by the Earth in amounts exceeding the needs of our civilization. The problem is only how to utilize this gifted energy.