An investigation of the transformation of Al-based metal-organic frameworks to mesoporous Al2O3 with core-shell and nanoporous structure

• Alumina was synthesized via direct thermal treatment of Al-based MOFs MIL-96.
• Alumina with hexagonal spindle-shaped morphology was obtained.
• The textural properties of alumina can be modulated by thermal treatment condition.
• The effect of thermal treatment conditions on the textural properties and formation mechanism were discussed.
• The effect of textural properties and inner structure on the adsorption ability of alumina were investigated.

Hexagonal spindle-shaped mesoporous alumina with different internal structures were prepared using Al-based metal-organic frameworks MIL-96 as precursor through thermal treatment method. MIL-96 and alumina products were characterized by XRD, SEM, TEM, BET and TG. Results from these characterizations showed that alumina products keep the morphology of their precursor, and the thermal treatment conditions have large effect on alumina microstructures. The state of atmosphere and heating rate are the main factors affecting the internal textural properties of alumina. A possible transformation mechanism was also proposed. In addition, the effect of textural properties and structure on the adsorption ability of alumina was investigated. This work presents a novel method, which builds a direct linkage between MOF crystals and metal oxide microstructures, to control the morphology, structure and performance of alumina and other metal oxide materials.

Hexagonal spindle-shaped alumina with different textural properties, which significantly affect the adsorption ability of alumina, were synthesized via direct thermal treatment of Al-based MOFs MIL-96.Figure optionsDownload as PowerPoint slide