Synthesis, characterization, X-ray structure, electrochemistry, photocatalytic activity and DFT studies of heterotrinuclear Ni(II), Pd(II) and Zn(II) complexes containing a formylferrocene thiosemicarbazone ligand

Three complexes of the general formula M{CpFe(eta(5)-C5H4CH=N-N=C(S)NH2}(2)[where M = Ni-II(2a), Pd-II(2b) and Zn-II(2c)] were synthesized with formylferrocene thiosemicarbazone (1) as a bidentate ligand. All compounds were characterized using conventional spectroscopic and analytical techniques (infrared,H-1 and(13)C NMR, mass spectrometry and elemental analysis). The molecular structure of2bwas confirmed by single-crystal X-ray analysis. To study the photocatalytic activity of the new complexes (2a-c), methylene blue (MB) was selected as a model pollutant. After 180 min, the degradation efficiency of MB reached 87% for2a, 76% for2band 85% for2c, and all complexes showed a higher photocatalytic activity than the formylferrocene thiosemicarbazone free ligand1. Theoretical studies were used to characterize the geometry and electronic structure of the compounds and to provide a rational explanation for the measured photocatalytic activity.