Pressure dependent chemical changes of adsorbed water in MIL-47 (V) by raman spectroscopy

Pressure-dependent structural and chemical changes of the metal-organic framework (MOF) compound MIL-47(V) have been investigated up to 2.9 GPa using pore-penetrating liquid, water as pressure transmitting medium (PTM). Under compression, MIL-47(V) undergoes reversible replacement of the free terephthallic acid (TPA) by H2O molecules near 0.7 and 1.5 GPa. The observed structural and chemical changes observed in hydroxyl linked vanadium octahedra in as-synthesised MIL-47(V) demonstrate unique high pressure chemistry depending on the type of bridging octahedral group in framework structure. The tunable bridging group in MIL-47(V) allows postsynthetic room temperature by pressureinduced removal and insertion of organic molecules in MOFs through the formation of stable phases at ambient conditions. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study investigates the structural and chemical changes of the metal-organic framework (MOF) compound MIL-47(V) under pressure using water as a pressure transmitting medium. The results show that MIL-47(V) undergoes reversible replacement of the free terephthallic acid (TPA) by H2O molecules during compression, and the hydroxyl linked vanadium octahedra exhibit unique high pressure chemistry. The tunable bridging group in MIL-47(V) enables the removal and insertion of organic molecules in MOFs through pressure induction.