Reversible intercalation of ammonia molecules into a layered double hydroxide structure without exchanging nitrate counter-ions

• Published in: Journal of solid state chemistry Vol. 183; no. 10; pp. 2324 - 2328
• Main Authors: Carbajal Arizaga, Gregorio Guadalupe, Wypych, Fernando, Castillón Barraza, Felipe, Contreras Lopez, Oscar Edel
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01-10-2010; Elsevier
• Subjects: ACETONE; ALUMINIUM COMPOUNDS; AMMONIA; CHARGED PARTICLES; CHEMICAL COATING; CHEMICAL VAPOR DEPOSITION; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); CLATHRATES; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Crystal structure; DEPOSITION; Electron density of states and band structure of crystalline solids; Electron states; Exact sciences and technology; Exchanging; EXPANSION; Fullerenes and related materials; intercalation compounds; HEAT TREATMENTS; HEATING; HYDRIDES; HYDROGEN COMPOUNDS; Hydroxide; HYDROXIDES; INFRARED SPECTRA; Intercalation; IONS; KETONES; Lattice dynamics; Layered; MATERIALS SCIENCE; Methods of deposition of films and coatings; film growth and epitaxy; NITRATES; NITROGEN COMPOUNDS; NITROGEN HYDRIDES; ORGANIC COMPOUNDS; OXYGEN COMPOUNDS; PH VALUE; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Phonons and vibrations in crystal lattices; Physics; Precipitation; Recycled; SPECTRA; STIRRING; SURFACE COATING; TEMPERATURE RANGE; TEMPERATURE RANGE 0400-1000 K; Zinc; ZINC COMPOUNDS; Layered; Ammonia; Hydroxide; Intercalation; Crystalline phase; Fourier transform spectroscopy; pH value; Hydroxides; Phase composition; Stirring; Aluminium; Nitrates; Intercalation compounds; Heat treatments; Zinc; CVD; Precipitation; Lamellar structure; Anhydrous compound; Calcium nitride; Vibrational modes; Fourier-transformed infrared spectrometry; Double layers; Acetone
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2010.07.050

A zinc/aluminum LDH was precipitated with recycled ammonia from a chemical vapor deposition reaction. The LDH presented a crystalline phase with basal distance of 8.9
Å, typical for nitrate-containing LDHs, and another phase with a basal distance of 13.9
Å. Thermal treatment at 150
°C eliminated the phase with the bigger basal distance leaving only the anhydrous nitrate-intercalated LDH structure with 8.9
Å. Intense N–H stretching modes in the FTIR spectra suggested that the expansion was due to intercalation of ammonia in the form of [NH
4(NH
3)
n
]
+ species. When additional samples were precipitated with pure ammonia, the conventional LDH nitrate structure was obtained (8.9
Å basal distance) at pH=7, as well as a pure crystalline phase with 13.9
Å basal distance at pH=10 due to ammonia intercalation that can be removed by heating at 150
°C or by stirring in acetone, confirming a unusual
sensu stricto intercalation process into a LDH without exchanging nitrate ions.
LDH-nitrate precipitated with ammonia expands the interlayer space if ammonia is bubbled up to pH 10. The basal distance decreased when the compound was heated at 150
°C or stirred in acetone. Nitrate ions are not exchanged.
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