To functionalize TiO₂ semiconductor nanoparticles, rigid-rod sensitizers, made of phenylethynyl and bicyclo[2.2.2]oct-1-ethynyl spacers substituted with a chromophore and two COOR binding groups, and tripodal sensitizers, consisting of a rigid-rod arm linked to a chromophore at one end and three COOR groups on the other end, have been synthesized and characterized. Ru^II-polybipyridyl complexes, pyrene, anthracene, azulene, and perylene were used as chromophores. These sensitizers with saturated and unsaturated bridges can distance the chromophoric groups 24Å from the surface of the semiconductor nanoparticles.