The photosensitized reduction reaction of methylviologen was investigated by tetrakis [(4-trimethylamino) phenyl] metalloporphyrins [MeTPI, Me=H2, Zn(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), Mn(Ⅲ), Co(Ⅲ)]. The kinetic parameter a, inductive time ti and initial rate v0 in photosensitized reaction were applied to measure the photosensitivity of photosensitizers. Both substituting groups and axial coordinations of metalloporphyrin can exert a great influence on the photosensitivity of photosensitizers. The experimental results domonstrated that (1) zinc porphyrin is the best photosensitizers in the same series of porphyrins and metalloporphyrins; (2) the aromatic organic bases can increase the photosensitivity through axial ligation, on the contrary, the aliphatic amines can decrease the photosensitivity; (3) the aromatic organic bases with positive charge can increase the photosensitivity considerably.

Key words: PHOTOSENSITIZATION, ZINC COMPLEX, COPPER COMPLEX, PHOTOCATALYSIS, COBALT COMPLEX, NICKEL COMPLEX, METHYL VIOLOGEN, PORPHYRIN, AXIAL LIGANDS