Synthesis, Crystal Structure, and Photocatalytic Properties of Two Novel Fe-Complexes Based on Oxalato Ligands

Abstract

Two novel water-insoluble six-coordinated complexes, catena-(N,N-pyridine or imidazole)-μ₂-oxalato iron(II) ((C₂₄H₂₀Fe₂N₄O₈)_n and (C₃₂H₃₂Fe₄N₁₆O₁₆)_n ⋅ C₂H₅OH, abbreviations: CPOFe or CIOFe, general term: COFe) have been prepared and characterized using single crystal X-ray diffraction, IR spectroscopy, element analysis, and UV-Vis spectroscopy. To investigate the catalytic properties, a simulated environment has been established. Methyl orange (MO) and Rhodamine B (RhB) have been chosen as model pollutants to characterize the photocatalytic system with hydrogen peroxide (H₂O₂) under visible light (λ ≥ 420 nm). The results indicate that COFe could effectively activate H₂O₂ to oxidize and mineralize the substrates in aqueous media under ambient conditions, e.g. temperature, pressure, and visible light irradiation. The degradation rate of RhB has been over 98% in an hour.