Synthesis and Raman spectroscopy of indium-based hydrotalcites of formula Mg6In2(CO3)(OH)16· 4H2O

✍ Scribed by Ray L. Frost; Sara J. Palmer; Laure-Marie Grand

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 220 KB
• Volume: 41
• Category: Article
• ISSN: 0377-0486
• DOI: 10.1002/jrs.2571

✦ Synopsis

Abstract

Insight into the unique structure of layered double hydroxides has been obtained using a combination of X‐ray diffraction and Raman spectroscopy. Indium‐containing hydrotalcites of formula Mg~4~In~2~(CO~3~)(OH)~12~· 4H~2~O [2:1 In‐LDH (layered double hydroxides)] through to Mg~8~In~2~(CO~3~)(OH)~18~· 4H~2~O (4:1 In‐LDH) with variation in the Mg : In ratio have been successfully synthesized. The d(003) spacing varied from 7.83 Å for the 2:1 LDH to 8.15 Å for the 3:1 indium‐containing layered double hydroxide. Raman spectroscopy complemented with selected infrared data has been used to characterize the synthesized indium‐containing layered double hydroxides of formula Mg~6~In~2~(CO~3~)(OH)~16~· 4H~2~O. Raman bands observed at around 1058, 1075 and 1115 cm^−1^ are attributed to the symmetric stretching modes of the CO~3~^2−^ units. Multiple ν~3~ CO~3~^2−^ antisymmetric stretching modes are found at around 1348, 1373, 1429 and 1488 cm^−1^ in the infrared spectra. The splitting of this mode indicates that the carbonate anion is in a perturbed state. Raman bands observed at 690 and 700 cm^−1^ assigned to the ν~4~ CO~3~^2−^ modes support the concept of multiple carbonate species in the interlayer. Copyright © 2010 John Wiley & Sons, Ltd.