Synthesis, characterization and photocatalytic studies of mesoporous silica grafted Ni(ii) and Cu(ii) complexes

Abstract

Mesoporous silica grafted nickel(II) and copper(II) complexes of a Schiff base ligand were synthesized. Functionalization of the ligand was achieved by Schiff base condensation of 3-APTES and O,O′-mono methylene bis(salicylidene). The Schiff base moiety was subsequently grafted with MCM41, followed by complexation with metal salts. The compounds were characterized by spectroscopy (Fourier transform infrared spectroscopy (FTIR), diffuse reflectance UV-Vis spectroscopy (DRS/UV-Vis), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS)), thermal analysis (Thermo Gravimetric Analysis (TGA)) microscopy (High Resolution Transmission Electron Microscopy (HRTEM)) and surface Brunauer–Emmett–Teller (BET) method, N₂-sorption isotherms analysis. The compounds were employed in the photo oxidation of Methyl Orange (MO) and Reactive Red198 (RR). The copper complex exhibits higher activity in the photo degradation of the dyes. The reusable photocatalysts show comparable activity to that of fresh catalyst without loss of their catalytic nature.