TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Compounds: The conductive layer is made of tin indium oxide, tin fluorine oxide, gallium oxide-zinc oxide, aluminum oxide doped zinc oxide, tin-based oxide, tin antimony oxide or zinc oxide. The semiconductor nanoparticle is selected from silicon, titanium oxide, tin oxide, zinc oxide, tungsten oxide, niobium pentoxide or titanium oxide doped with strontium. The counter electrode contains platinum, gold, nickel, copper, silver, indium, ruthenium, iridium, palladium, rhodium, osmium or carbon. The ion liquids comprise cations and anions, where the anions are selected from iodide, bromide, chloride, (N(CN)2)-, (N(SO2CF3)2)-, (PF6)-, (BF4)- or (NO3)-.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Compounds: The quinolinecarboxylic acid is selected from the compounds of general formulae (XV-XXI). The photo-absorbing layer contains a semiconductor nanoparticle layer and a dye layer, where the semiconductor nanoparticle layer is connected with the conductive layer and the dye layer is connected with the reduction layer. The cations are selected from the aromatic compounds of general formulae (XXI-XXIX). The organic transport material is 2,2',7,7'-tetrabis(N,N-di-P-methoxylamine)9,9'-spirobifluorene or other organic P-type semiconductor. The electrolyte layer contains iodine or iodine salt electrolytes, ion liquids, organic transport materials and inorganic transport materials, where the ion liquids comprise cations and anions, where the anions are selected from (C(CN)3)-, (B(CN)4)-, (CF3COO)-, (ClO4)-, (BF3CF3)-, (CF3SO3)-, (CF3F2SO3)-, (CH3H2SO3)-, ((CF3 SO2)2N)-, ((C2H5 SO2)2N-, ((CF3SO2)3C)-, ((C2F5SO2)3C)-, ((FSO2)3C)-, (CH3CH2OSO3)-, (CF3C(O)O)-, (CF3CF2C(O)O)-, (CH3CH2C(O)O)-, (CH3C(O)O)-, (P(C2H5)3F3)-, (P(CF3)3F3)-, (P(C2H4H)(CF3)2F3))-,(P(C2F3H2)3F3)-, (P(C2F5)(CF3)2F3)-, (P(CF3)3F3)-, (P(C6H5)3F3)-, (P(C3H7)3F3)-, (P(C4H9)3F3)-, (P(C2H5)2F4)-, ((C2H5)2P(O)O)-, ((C2H5)2P(O)O2)-, (PC6H5)2F4)-, ((CF3)2P(O)O)-, ((CH3)2P(O)O)-, ((C4H9)2P(O)O)-, (CF3P(O)O2)-, (CH3P(O)O2)-, ((CH3O)2P(O)O)-, (BF2(C2F5)2)-, (BF3(C2F5))-, (BF2(CF3)2)-, (B(C2F5)4)-, (BF3(CN))-, (BF2(CN)2)-, (B(CF3)4)-, (B(OCH3)4)-, (B(OCH3)2(C2H5))-, (B(O2C2H4)2)-, (B(O2C2H2)2)-, (B(O2CH4)2)-,(N(CF3)2)-, (AlCl4)- or (SiF6)2-.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The conductive polymer is polyaniline, polypyrrole, polythiophene, poly(p-substituted phenylacetylene) or polyether. The transparent substrate layers are made of glass or plastic, where the plastic is selected from ethylene glycol polyterephthalate, ethylene glycol polynaphthalate, polycarbonate, polypropylene, polyimide, triacetyl cellulose and polyether sulfone.