Efficient synthesis of UiO-66 nanocrystals and their use as a template for the preparation of Ag,In/ZrO2 catalysts

M.A. ULLA; J.M. ZAMARO; LOZANO L.

Santa Fe

Congreso; VI San Luis Conference; 2018

Universidad Nacional del Litoral

In this work we first implement a more eco-sustainable synthesis of UiO66, using acetone as alternative solvent in replacement of the expensive and toxic Dimethylformamide (DMF). Different preparation protocols for the synthesis mixtures, solvent proportion, temperature and time of treatment were analyzed. We find that the reagent homogenization stage had a critical effect on the development of Zr-MOF in acetone and optimal results were obtained using a molar ratio BDC:ZrCl4:acetone 1:1:1622, prepared with magnetic stirring and solvothermally treated for 24 h at 80°C. The obtained MOF showed high crystallinity, crystals size of 150 nm, excellent thermal stability and microporosity with a specific surface of 1299 m2/g. These properties are similar to those reported for crystals traditionally obtained in DMF. Subsequently, the MOF nanocrystals were used as a template to obtain Ag and In derived-catalysts, which were explored in their catalytic behavior using the CO oxidation. The precursors of active species were infiltrated in the MOF by impregnation and then UV radiation and thermal treatments were employed to prepare the catalytic phases. We obtained the Ag/t-ZrO2 system that was active and stable in reaction as well as the In/t-ZrO2 system, which showed an interesting activity. The study provides information on the formation, development and performance of MOF-derived metal-ZrO2 catalytic systems