Synthesis and characterization of CoFe2O4@TiO2@HKUST-1 as a novel metal-organic framework nanocomposite

Abstract

A novel metal–organic framework-based nanocomposite has been designed and synthesized via a two-step procedure. First, CoFe2O4@TiO2 nanoparticles have been prepared through initial formation of CoFe2O4 nanoparticles, followed by introduction of TiO2 by using titanium tetraisopropoxide. Subsequently, HKUST-1 metal–organic framework has been formed through self-assembly of Cu(NO3)2·3H2O and trimesic acid in the presence of CoFe2O4@TiO2 nanoparticles. The properties of the resultant nanocomposite, CoFe2O4@TiO2@HKUST-1, have been analyzed via XRD, TGA, TEM, SEM, BET, VSM and FTIR and compared with those of HKUST-1, CoFe2O4@TiO2 and CoFe2O4. It was found that the nanocomposite showed lower specific surface area compared to HKUST-1. Moreover, incorporation of CoFe2O4@TiO2 resulted in significant morphological change. VSM analysis implied that the magnetic properties of CoFe2O4@TiO2 and the nanocomposite were lower than that of CoFe2O4. However, they could be magnetically separated by using an external magnet.