Construction of acylhydrazidate-extended metal-organic frameworks

Area of Science:

• Materials Chemistry
• Inorganic Chemistry
• Crystallography

Background:

• Metal-organic frameworks (MOFs) are crystalline materials constructed from metal ions and organic linkers.
• MOFs offer tunable structures and properties, making them suitable for various applications.
• Acylhydrazidate ligands derived from aromatic polycarboxylic acids and hydrazine are explored for MOF synthesis.

Purpose of the Study:

• To synthesize and characterize new acylhydrazidate-extended metal-organic frameworks (MOFs) using hydrothermal methods.
• To investigate the structural diversity and topological properties of the newly formed MOFs.
• To evaluate the photoluminescence and gas adsorption capabilities of the synthesized MOFs.

Main Methods:

• Hydrothermal synthesis involving Ba(2+)/Zn(2+) ions, aromatic polycarboxylic acids, and hydrazine.
• X-ray single-crystal diffraction analysis for detailed structural elucidation.
• Photoluminescence spectroscopy and nitrogen adsorption measurements at 77 K.

Main Results:

• Four new MOFs were successfully synthesized: [Ba(pmdh)], [Ba(sdpth)(H2O)2]·0.5H2O, [Ba2(cpth)2(H2O)2], and [Zn2(pdh)2(ox)]·H2O.
• Structural analysis revealed diverse network topologies, including 1D square tubes, 2D layers extended to 3D networks, and complex 3D frameworks with secondary building units.
• Compounds 3 and 4 exhibited green photoluminescence, and MOFs 2 and 4 demonstrated significant N2 adsorption capacities at 77 K.

Conclusions:

• The hydrothermal reaction conditions allow for the formation of novel acylhydrazidate-based MOFs with varied dimensionalities and topologies.
• The synthesized MOFs display promising photoluminescent and gas sorption properties, indicating potential applications in sensing and gas storage.
• This study expands the library of MOFs and highlights the versatility of acylhydrazidate ligands in constructing functional materials.