| Abstract
| - l-Aspartic acid (l-Asp) has been intercalated into magnesium−aluminum layered double hydroxides bycoprecipitation. The structure and composition of the intercalated material have been studied by X-raydiffraction, inductively coupled plasma emission spectroscopy, and elemental analysis. A schematic modelof the intercalated structure has been proposed. Furthermore, the thermal decomposition of the hybrid materialhas been characterized by in situ powder X-ray diffraction, in situ Fourier transform infrared spectroscopy,thermogravimetry, differential thermal analysis, 13C solid-state magic-angle spinning nuclear magneticresonance, temperature-programmed decomposition, and gas chromatography−mass spectrometry. Thethermolysis of l-Asp LDH is quite different from that of the pristine l-Asp studied as a reference sample andis characterized by three steps: the first from room temperature to 150 °C is attributed to the loss of bothadsorbed and interlayer water, accompanied by the destruction of the hydrogen bonding network and a decreasein basal spacing; the second step (250∼350 °C) involves the polymerization and deamination of l-Asp ionsin the interlayer of LDH and dehydroxylation of the brucite-like layers; the third step in the temperatureregion of 350∼450 °C corresponds to dehydroxylation of the brucite-like layers as well as further decompositionof interlayer materials.
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