Synthesis and characterization of metal organic framework MOF-199 doped with sodium cations for hydrogen storage at ambient temperature

Abstract

Over the last decade, metal-organic frameworks have been widely used as new options for hydrogen storage. The high surface area and regular pores cause these materials are good options for hydrogen storage. In this study sodium ions were introduced in (Cu3 (BTC)2)MOF-199 holes with in situ method, and its hydrogen adsorption performance was measured at room temperature. The structure and morphology of the proposed new MOF ((Na.Cu3(BTC)2)) was recognized with various techniques including TG, BET, SEM, FTIR and XRD. The results showed that after introducing sodium ions in the MOF, the main structure did not changed and the surface area increased from 1300 m2g-1 to 1434 m2g-1 and the hydrogen adsorption increased from 1 to 1.4 wt% (40% increase). The increase in hydrogen adsorption after sodium doping may be due to growing surface area and physical interaction between hydrogen molecules and sodium ions (increasing binding energy).Therefore, sodium ions act as additional sorption sites and adsorb hydrogen molecules.

Keywords

• metal organic framework mof-199
• hydrogen storage
• sodium doping
• nanoporous materials
• in situ synthesis