Structure stability of metal-organic framework MIL-53 (Al) in aqueous solutions

• MIL-53 (Al) is stable and highly resistant to hydrolysis in neutral and acidic solutions.
• The good structure stability of MIL-53 (Al) to aqueous solutions is quite rare among the MOFs.
• In aqueous basic solution, MIL-53 (Al) undergoes structure transformation.

The structural stability of MIL-53 (Al) in different pH aqueous solutions from room temperature to 100 °C has been investigated. Experimental results show MIL-53 (Al) is stable and highly resistant to hydrolysis in neutral and acidic solutions. It can retain its crystallinity and permanent porosity without structural collapse. The good structure stability of MIL-53 (Al) to aqueous solutions is quite unusual among the MOFs. The nitrogen adsorption for the soaked frameworks show a typical type I isotherm. In basic aqueous solution, MIL-53 (Al) undergoes structure transformation.