CHARACTERIZATION OF [FE(O-PHEN)(3)][NI(CS3)(2)] AS A PHOTOSENSITIZER FOR WIDE-BAND GAP SEMICONDUCTOR (ZNO) ELECTRODES IN ACETONITRILE MEDIA

A newly synthesized transition metal complex tris-1,10-ortho-phenanthr oline iron (II) bis-thiocarbonato nickelate (II), [Fe(o-phen)(3)] [Ni( CS3)(2)], has been studied for its photosensitizing properties at n-Zn O semiconductor electrodes prepared by spray pyrolysis and sol-gel tec hniques. The absorption spectrum of this inorganic complex in acetonit rile solution exhibits a strong peak at 462 nm and a shoulder at 510 n m wavelength of light. From cyclic voltammetric studies it has been fo und that this compound can undergo reversible, one-electron transfer o xidation with formal redox potential E(0) = 0.985 V vs. SSCE in aceton itrile medium. The sensitization of the photocurrent at the ZnO electr ode by the test dye was confirmed by determining current-potential cur ves and action spectrum. As compared with sprayed ZnO thin films, part iculate films prepared by sol-gel technique were found to give better performance.