Two new heteroleptic ruthenium (II) photosensitizers that contains 2, 2′; 6, 2′′- terpyridine with extended π-conjugation with donor groups, a 4, 4′-dicarboxylic acid-2, 2′- bipyridine anchoring ligand and a thiocyanate ligand have been designed, synthesized and fully characterized by CHN, mass spectrometry, UV-vis and fluorescence spectroscopies and cyclic voltammetry. The new sensitizers have either 3, 5-di-tert-butyl phenyl (m-BL-5) ...