NOVELTY - A photoelectrochemical solar cell is constructed by depositing on electrode a mesoporous nanocrystalline titanium dioxide film; and depositing a drop of gel, consisting of nanocomposite organic-inorganic material incorporating iodine gas and iodide salt, on the top of the electrode supporting titanium dioxide/dye system.    USE - For construction of photoelectrochemical solar cell used as self-sustained device for the conversion of light into electricity for any application requiring small or high power, including as photovoltaic window in apparatuses or in buildings (claimed).    ADVANTAGE - The active surface of titanium dioxide is increased, accordingly increasing the quantity of adsorbed organic photosensitizer and the overall efficiency of the cell. Efficiency is also increased by the use of solid gel electrolyte where solvents are incorporated in the structure of the electrolyte that enhances electric conductivity.    DETAILED DESCRIPTION - Construction of photoelectrochemical solar cell made from nanocomposite organic-inorganic materials, deposited as fluid gels, subsequently transformed into solid gels, composed into a self-sustained photovoltaic apparatus for production of electric energy, involves:    (a) cutting a transparent electroconductive tin dioxide:fluorine or indium tin oxide (1) or other electrode from a commercially available plate;    (b) depositing on this electrode a mesoporous nanocrystalline titanium dioxide film (2), either of anatase or a mixture of anatase with rutile;    (c) synthesizing a gel containing a redox couple which will be deposited on the titanium dioxide/dye surface; and    (d) depositing a drop of the gel, while it is still a fluid, on the top of the electrode supporting the titanium dioxide/dye system and then sandwiching and spreading it between the above and the counter electrode, where, by choice, a thin layer of platinum can be deposited.    The mesoporous nanocrystalline titanium dioxide film is deposited on the electrode by solvolysis and polymerization of titanium isopropoxide without added water in the presence of organic acid and surfactant which acts as template; deposition of the material (a) as nanocomposite organic-inorganic film on the transparent electroconductive glass; calcination of the above material at high temperature; and adsorption of the ruthenium organometallic complex cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium (II) or any other equivalent commercially available substance which acts as photosensitizer of titanium dioxide.    The gel electrolyte (3) consists of nanocomposite organic-inorganic material incorporating iodine gas and iodine salt which is synthesized by solvolysis and polymerization of derivatives of alkoxysilanes or alkoxy titanates or of alkoxides of other metals, according to the sol-gel method in the absence of water, in the presence of organic acid and, possibly, in the presence of surfactant and organic solvents.    An INDEPENDENT CLAIM is also included for a photoelectrochemical solar cell composed of nanocomposite organic-inorganic materials made by this method, composed into a self-sustained photovoltaic device that transforms light energy into electric energy.    DESCRIPTION OF DRAWING(S) - The figure shows a cross-sectional view of photoelectrochemical solar cell.    Transparent electroconductive electrode (1)    Mesoporous nanocrystalline titanium dioxide film (2)    Gel electrolyte (3)    Positive electrode (4)