Generation of energy from renewable and CO2-neutral sources is one the greatest 21th Century's challenges. Solar energy is by far the most abundant of these sources. Solar energy utilization requires solar capture and conversion as well as storage. Solar capture and conversion may be accomplished by photovoltaics. Currently, solar photovoltaic technology is based on silicon. However, the high production cost of the crystalline silicon makes this technology too expensive and the development of this industry has been only possible based on government subsidies. On the other hand, no substantial changes are expected in this technology as its efficiency is already quite close to the thermodynamic limit (about 30%) and no substantial decrease in the cost of the production of silicon is expected.
Polymer photovoltaic cells are in principle attractive as their production cost is low because they can be produced using conventional coating methods, but their efficiency and life-time are not enough to make these systems commercially competitive. Solar electricity cannot be used as primary energy source, because of the diurnal variation in local isolation. Therefore, batteries should be used and for this purpose. Organic batteries are promising. Photocatalysys provides an attractive method to capture and storage solar energy in chemical bonds. Thus, conjugated microporous polymers incorporating metal nanoparticles are promising photocatalyst for water-splitting.