TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Particles: The dye is adsorbed by using a solution containing the anionic sulfonic acid derivative and the dye.The dye absorbance is carried out by first allowing the anionic organic sulfonic acid derivative to be absorbed by semiconductor particles and then allowing the dye to be adsorbed.The anionic organic sulfonic acid derivative is of formula R1-(Ar)m-L1-SO3-M+ (I), preferably a compound of formula R2-Ph-O-(CH2-CH2O)n-L2-SO3-M+ (II);R1 = H, (un)substituted alkyl group;Ar = (un)substituted arylene;m = 0,1;L1 = single bond or a divalent linking group; andM+ = cation, with the proviso that a combination of a hydrogen atom as R1, 0 as m, and a single bond as L1 is excluded;R2 = straight or branched alkyl group;Ph = phenylene group;n = 0-50;L2 = sinlge bond, (un)substituted alkylene, (un)substituted alkyleneoxy group.Preferred Dye: The dye is selected from organic metal complex dyes, phthalocyanine dyes, porphyrin and polymethine dyes.The semiconductor particles are metal oxide(s) selected from TiO2, TiSrO3, WO3, Nb2O5, and SnO2.The semiconductor particles have a charge transporting layer comprising a molten salt electrolyte and a counter electrode.The charge transporting layer comprises a room temperature molten salt which mainly comprises an imidazolium salt and contains no volatile components. L1 = (un)substituted alkylene, -O- and/or divalent linking group;    M+ = alkali metal ion.    EXAMPLE - In the manufacturing process:    (1) A transparent electrically-conductive substrate (photoanode) was prepared by uniformly coating a 1.9 mm thick alkali-free glass sheet with fluorine-doped dioxide by CVD to give a 600 nm thick substrate having a surface resistivity of about 15 OMEGA/square and a light transmission (500 nm) of 85%;    (2) A titanium dioxide-containing coating composition was prepared by preparing a titanium dioxide dispersion from tetraisopropoxide in accordance with method by C.J. Barbe et al J. Am. Ceram, Soc., vol. P.3157 (1997), except that the autoclave temperature was 230 degreesC. Polyethylene glycol (average molecular weight: 20,00) (30 wt.%) was added to the dispersion to prepare a viscous coating composition;    (3) The coating composition was applied to the electrically-conductive layer side of the transparent electrically-conductive substrate prepared in (1) to a thickness of 100 microns, dried at 25 degreesC for 60 minutes, and fired at 500 degreesC for 30 minutes to form a titanium dioxide layer. The coating weight and thickness of the titanium dioxide layer were 10 g/m2 and 8 microns respectively;    (4) a ruthenium complex dye was dissolved in a dried mixture of acetonitrile and t-butanol in a concentration of 32 x 10-4 mol/l, and a pasty organic sulfonic acid derivative was dissolved in it at a concentration of 0.025 mol/l;    (5) the TiO2-coated glass substrate was immersed in the dye solution prepared in (4) and allowed to stand for 3 hours at 40 degreesC while stirring. The dyed gas substrate was washed with ethanol and dried to prepare a dye-sensitized electrode. The amount of dye absorbed was 1.2 x 10-3 mol/m2. The light absorption wavelength of the electrode was 800 nm at the longest.    A dye-sensitized electrode was prepared in the same manner as above but replacing the above dye with a black dye having a longer wavelength. The light absorbance wavelength of the resulting electrode was about 900 nm at the longest.    In order to prepare the photocell, the TiO2 layer of the dye-sensitized electrode was scraped off leaving a circle of 8 mm in diameter as a light-receiving area. A platinum-deposited substrate was superposed on the electrode with a polyethylene film flame spacer of heat pressure bonding type (thickness: 20 nm) interposed inbetween. The two electrodes were pressure bonded while heating the scraper to 120 degreesC and the edges of the cell were sealed with an epoxy resin adhesive. A room temperature molten salt was made to penetrate into the gap between the electrodes. All the steps of cell assembly and penetration were carried out at in dry air having a dew point of -60 degreesC. The inside of the cell was evacuated by suction in vacuo for several hours to remove air and the small hole was closed with low melting glass.    Thus, wet type photocells were obtained comprising dye-sensitized semiconductor.