Light harvesting properties of some new heteroleptic dithiocarbimate–diamine/diimine complexes of Ni, Pd and Pt studied as photosensitizer in dye-sensitized TiO2 solar cells†
Abstract
This contribution describes the light harvesting efficiencies of new heteroleptic complexes of the form [M(L)(L′)] where L = p-tolylsulfonyldithiocarbimate (p-CH3C6H4SO2NCS22−); M = Ni(II), L′ = 2,2′-bipyridine (bpy) (1) or 1,10-phenanthroline (phen) (2) or N,N,N′,N′-tetramethylethylenediamine (tmed) (3); M = Pd(II), L′ = bpy (4) or phen (5) or tmed (6); and M = Pt(II), L′ = bpy (7) or phen (8) or tmed (9). These have been characterized by elemental analysis, IR, 1H and 13C NMR and UV-visible spectroscopies, and 1, 4 and 6 by single crystal X-ray diffraction. UV-visible absorption, electrochemical behavior and structural features of the ligand aromatic sulfonyldithiocarbimate containing free sulfonyl oxygen atoms serving as a typical anchoring group on TiO2 semiconductor electrode of the nickel complexes enable them to act as potential photosensitizers for solar energy conversion. This study widens the scope for square planar heteroleptic complexes with a suitable combination of metal ions and ligands to be explored as photosensitizers.