| abstract |
Provided is a novel photosensitizer having a large extinction coefficient that absorbs light in a wide range of visible light and has high light absorption efficiency even in an extremely thin thin film. A photosensitizer for a metal oxide semiconductor electrode comprising a metal complex represented by the general formula (I), which is adsorbed to the metal oxide semiconductor electrode via a ligand L 1 or L 2. A photosensitizer characterized in that the difference ΔL in energy level between the excited states calculated by using GAUSSIAN03 quantum chemistry program calculation of L 1 and L 2 is 0.25 eV or more. ML 1 L 2 X 2 (I) (M represents a Group 8 transition metal in the periodic table, X represents a halogen atom, a cyano group, a thiocinanate group, an isothiocyanate group, an isocyanate group, an isocyanide group, a hydroxy group, or a bidentate ligand in which Xs are bonded to each other. L 1 and L 2 are ligands containing an aromatic ring, and have a functional group having a COOH group or PO (OH) 2 in either L 1 or L 2 . [Selection] Figure 1 |