Polyoxometalate functionalized matrix material: synthesis, characterization, reductive and thermal degradation kinetics

Abstract

Abstract: One-pot synthesis of polyoxometalate (POM) based hybrid material 1 was synthesized by mixing copper nitrate, silicomolybdic acid and urea under hydrothermal condition. The reduction ability of 1 was examined by employing 2,4,6-trinitrophenol (2,4,6-TNP) and 4-nitrophenol (4-NP) in the presence of sodium borohydride in water. The catalytic reduction into the corresponding amine was monitored by UV–Visible spectroscopy. The rate and order of catalytic reduction were studied through chemical kinetics and follows pseudo-first-order. The efficiency of the catalyst was investigated by employing used catalyst 1 for at least ten cycles. Leaching experiments and performance of the reusability of catalyst were supported by FT-IR analyses. In addition, the electrochemical reduction ability of catalyst 1 was also executed by Cyclic Voltammetry (CV). Catalyst 1 was characterized by Fourier-Transform Infrared spectroscopy (FT-IR), Powder X-ray diffraction (PXRD), UV-Diffused Reflectance (UV DRS), Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDX), X-ray Photoelectron Spectroscopy (XPS), and Bruner–Emmet–Teller analyses (BET). Solid-state decomposition kinetics of 1 was performed from Thermogravimetric Analysis (TGA) data by fitting into model equations such as Flynn–Wall–Ozawa (FWO) and corrected (C-FWO). Graphic abstract: [Figure not available: see fulltext.].