Morphological and structural evolution of mesoporous calcium aluminate nanocomposites by microwave-assisted synthesis

Autor: Po Hsueh Chang, San-Yuan Chen, Yen Ho Lai, Yen Po Chang, Tai Jung Lee, Yuan Tse Lee
Rok vydání: 2014
Předmět:
Zdroj: Microporous and Mesoporous Materials. 183:134-142
ISSN: 1387-1811
DOI: 10.1016/j.micromeso.2013.09.013
Popis: Novel special dual-structure calcium aluminate nanocomposites consisting of mesoporous Ca-containing Al 2 O 3 nanonetworks with Ca 12 Al 14 O 33 polycrystalline nanorods have been successfully synthesized using the microwave-hydrothermal (M-H) process in an alcohol solution consisting of calcium nitrate and mesoporous alumina, followed by calcination at a lower temperature (e.g., less than 600 °C). The mesoporous Ca-containing aluminate nanocomposites possessed a specific surface area of 51 m 2 g −1 and a broad pore size distribution of 4–12 nm in diameter, as observed from N 2 adsorption/desorption measurements. The results showed that highly dispersed Ca 12 Al 14 O 33 nanorods grown on the mesoporous nanostructure were obtained by varying the molar ratio of Ca/Al or by controlling microwave heating time, as characterized by scanning electron microscopy (SEM), transmission electron microscopy/electronic energy loss spectroscopy (TEM/EELS) and powder X-ray diffraction (PXRD). The Ca 12 Al 14 O 33 nanorods with diameters of 50–100 nm and lengths of 200–400 nm were grown in and on the one-dimensional mesochannels. A formation mechanism of the mesoporous Ca-containing aluminate nanocomposites involving amorphous mesoporous hydrated-Al 2 O 3 was also proposed.
Databáze: OpenAIRE
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