The synthesis, spectral and photoelectrochemical studies of mixed ligand complexes of [Ru(dcbpy)(2)(LL)]Cl-2, where LL = 2,4-(1,3-N,N'-dimethyl)pteridinedione (DMP), 6,7-dimethyl-2,4-(1,3-N,N'-dimethyl)pteridinedione (MDMP), 6,7-diphenyl-2,4-(1,3-N,N'-dimethyl) pteridinedione (PhDMP), dibenzo[h,j]-(1,3-N,N'-dimethyl)isoalloxazine (BIAlo), 6,7-bis(pyrid-2-yl)-2,4-(1,3-N,N'-dimethyl) pteridinedione (PyDMP) were carried out. These complexes were attached to sol-gel processed TiO2 electrodes and the photocells fabricated were illuminated with polychromatic radiation in the presence of I-2/I-3(-) as redox electrolyte. The incident photon to current conversion efficiency determined was found to be similar to20-48%. (C) 2002 Elsevier Science B.V. All rights reserved.