Sorptive Capture and Photo-Catalytic Degradation of Methylene Blue from Aqueous Solution Using Lead-Organic Frameworks

摘要

A wide range solubility of water is the main cause of its contamination by variety of inorganic/organic pollutants and hence needs decontamination using various porous materials. It is needed and still is a challenging task of time to develop porous materials like metal organic frameworks for the said purpose. In this study, we report sorptive removal and photo-catalytic degradation of methylene blue (MB) using newly synthesized MOFs (1–4) of Pb2+ ions with 2-bromoterphthalic acid (H2BTA) and 5-hydroxyisophthalic acid (H2HIA). The prepared MOFs have been well characterized by means of FT-IR, UV/Vis, 1H NMR, powder X-ray diffraction, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), thermo-gravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) studies. BET surface area was found to be 2866.5 m2/g for 1, 3266.5 m2/g for 2, 605 m2/g for 3, and 1054 m2/g for 4, making them good candidates for MB removal and its degradation. The results showed that morphological properties and surface structures affect the sorption, thermodynamic and kinetic process. Photo-catalytic degradation efficiency of these MOFs was in the range 80–99% as follows: MOF-1 (99%) > MOF-2 (98%) > MOF-3 (80%) > MOF-4 (84%).