Synthesis and Characterization of Zirconium-Based Metal Organic Frameworks (UiO-66) Double Ligands with Amine-Carboxylic Acid (NH₂-H₂BDC) using Solvothermal Method

¹ Civil Engineering Programme, Faculty of Engineering, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu, Sabah 88400, Malaysia
² Oil and Gas Engineering Programme, Faculty of Engineering, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu, Sabah 88400, Malaysia
³ Faculty of Engineering, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu, Sabah 88400, Malaysia

^* Corresponding author: snfarhanazakaria@ums.edu.my

Abstract

In this study, zirconium-based metal organic frameworks (MOFs) of the UiO-66 type were synthesized by the solvothermal method using traditional solvent, N,N-Dimethylformamide (DMF). A composition of terephthalic acid (H2BDC) and 2-amino terephthalic acid (NH2-H2BDC) with a molar ratio of 1:0, 1:0.5, 1:1, 1:1.5, 1:2, 1:3, 0:1, and 0:2 was used as an organic ligand to synthesize the UiO-66 samples. Eight samples of UiO-66 were synthesis at a temperature of 120°C for 24 hours through solvothermal method to produce highly crystalline structures of UiO-66. The successful modification of organic ligands and crystallinity of the UiO-66 samples were verified through X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Brunauer-Emmett-Teller (BET) analysis. The addition of amine groups (NH2) developed new active sites, as shown by the vibrational bands of N-H and C-N, without disturbing the integrity of the UiO-66 structure. Based on the BET analysis, amine functionalization caused the surface area of UiO-66 decrease slightly, while preserving mesoporous characteristics suitable for adsorption applications. The modified UiO-66 materials demonstrated enhanced chemical functionalities, which made UiO-66 as an attractive candidate for the treatment of water and wastewater and industrial applications, particularly in selective adsorption and catalysis.