STUDY OF THE EFFECT OF Nb2O5 ADDITION IN MOF FROM ZrCl4 WITH 1,4-BENZENEDICARBOXYLIC ACID (H2BDC) AS HYDROGEN STORAGE MATERIAL

• Main Author: HUSNI WAHYU WIJAYA (NIM : 20510007); Pembimbing 1 : Prof. Djulia Onggo, Ph.D; Pembimbing 2: Aep
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/15961
• Institution: Institut Teknologi Bandung

Hydrogen gas can be used as an alternative energy because fossil fuel demands increase rapidly while its supply is unrenewable and the product of fuels combustion is CO2 that caused greenhouse effect. The storage of H2 gas needs a large tank with high pressure caused impractical equipment. To overcome this problem the H2 gas can be stored in materials such as metal hydride or porous materials. However, mass per volume for metal hydride is high so porous materials become candidate for hydrogen storage especially metal-organic frameworks (MOFs). MOFs are coordination compound from metal ion or cluster with bridging ligand (organic ligand) built frameworks coordination polymer and formed porous material. The porous are host filled by guest molecule such as hydrogen and make them as storage. And also, MOFs is promising material for hydrogen storage because it has large surface area and highly porosity so the hydrogen adsorption should be higher than the other porous materials. Metals and/or organic ligands that formed of MOFs can be vary or addition other materials to the MOFs will enhance the amounts of hydrogen storage. MOF from ZrCl4 with 1,4-benzenedicarboxylic acid was reported and has high hydrogen up take, thermal stability, and relatively chemical resistance. In this research we reprepared this MOF using different technique, Schlenk technique at 120 oC 24 h, produced white solid contained cluster Zr6O4(OH)4(CO2)12. This cluster revealed by appeared peak at 20 7.4 and 8.6 from XRD pattern and at IR region showed peaks at 1589 and 1395 cm-1 indicated strecting of carboxylate groups, CO2, and triple peaks at 549, 654, and 746 cm-1 for longitudinal and transverse modus of Zr─O2. Pore parameters such as Langmuir surface area 847.330 m2/g, BET surface area 539.785 m2/g, micropore area 59.11%, and pore diameter 2.977 nm measured by isotherm adsorption. This result showed that surface area smaller than previous reported. The addition of Nb2O5 on those MOF produced white powder with same parent structure. Confirmation using XRD and IR measurements showed that the specific peaks are similar as reported, except appeared Nb2O5 peaks at XRD in this material. Nb2O5 that added caused increasing Langmuir surface area up to 250 m2/g, increasing BET surface area up to 75 m2/g, micropore area become 81.16%, and pore diameter become 3.551 nm. The particle size by SEM analysis is around 300 nm. In addition, MOF niobium based tried to synthesis by solvothermal with varying temperature and time of reaction. Reaction at 200 oC 24 hours produced brown-yellow powder but when run at 180 oC 3 days produced white powders. Both products analyzed using IR, XRD, and thermogravimetry showed that both of them not MOFs like as target.