Cobalt-Imidazole Complexes: Effect of Anion Nature on Thermochemical Properties

• Published in: Materials Vol. 17; no. 12; p. 2911
• Main Authors: Netskina, Olga V, Sukhorukov, Dmitry A, Dmitruk, Kirill A, Mukha, Svetlana A, Prosvirin, Igor P, Pochtar, Alena A, Bulavchenko, Olga A, Paletsky, Alexander A, Shmakov, Andrey G, Suknev, Alexey P, Komova, Oxana V
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 14-06-2024; MDPI
• Subjects: Air bags; Chemical analysis; Cobalt; cobalt complex; Cobalt oxides; Composition; Critical temperature; Decomposition; gas-generation composition; Gases; Gasification; high-energy ligand; Hydrogen bonds; Imidazole; Infrared spectroscopy; Ligands; Nitrates; Nitrogen; Oxidation; oxidizing anion; Satellites; solvent-free synthesis; Spectrum analysis; Thermal decomposition; Thermal stability; Thermochemical properties; X ray photoelectron spectroscopy; imidazole; cobalt complex; oxidizing anion; high-energy ligand; cobalt oxide; solvent-free synthesis; gas-generation composition
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17122911

A solvent-free method was proposed for the synthesis of hexaimidazolecobalt(II) nitrate and perchlorate complexes-[Co(C
H
N
)
](NO
)
and [Co(C
H
N
)
](ClO
)
-by adding cobalt salts to melted imidazole. The composition, charge state of the metal, and the structure of the resulting complexes were confirmed by elemental analysis, XPS, IR spectroscopy, and XRD. The study of the thermochemical properties of the synthesized complexes showed that [Co(C
H
N
)
](NO
)
and [Co(C
H
N
)
](ClO
)
are thermally stable up to 150 and 170 °C, respectively. When the critical temperature of thermal decomposition is reached, oxidative two-stage gasification is observed. In this case, the organic component of the [Co(C
H
N
)
](NO
)
complex undergoes almost complete gasification to form Co
O
with a slight admixture of CoO, which makes it attractive as a component of gas-generation compositions, like airbags.