TY - JOUR
T1 - Optimum synthesis of mesoporous silica materials from acidic condition
AU - Lin, Hong Ping
AU - Kuo, Chin Lung
AU - Wan, Ben Zu
AU - Mou, Chung Yuan
N1 - Funding Information:
Author is supported by the Danish Council for Independent Research - Technology and Production Sciences (FTP) and Natural Sciences (FNU) grant number 274-09-0096.
Funding Information:
★ Author is supported by the Danish Council for Independent Research - Technology and Production Sciences (FTP) and Natural Sciences (FNU) grant number 274-09-0096.
PY - 2002
Y1 - 2002
N2 - On the basis of the mixtures composed of CnTMAB/acids/TEOS/ water, the mesoporous materials with well-ordered hexagonal structures can be synthesized under acidic condition (pH < 1.0) with a careful control of the silica condensation. However, the induction period time for the formation of surfactant-silica precipitation varied with the employed acid source and decreased in the series: HNO3 < HBr < HCl < H 2SO4 at the same acid concentration. Increasing the acid concentration not only induced a fast precipitation rate, but also provoked more nuclei seeds formation and reduced the particle size of the mesoporous silica products. A proper aging time is also significant for getting the well-ordered mesoporous materials via acid route, and a longer aging time would induce a gradual decomposition of the mesostructures. For morphology, in acid synthetic medium, various interesting shell-like curved patterns on the surface of mesoporous silica particles were formed. The physical properties (such as d-spacing, pore size, BET surface area and porosity) of the calcined mesoporous silica are almost not affected by the nature of the acid source, but the pore size of the mesoporous materials can be tailored by varying the chain length of the surfactant. Adding the proper amount of ammonia solution for adjusting the pH value between 8-10 can improve the hexagonal mesostructures order of the mesoporous materials while maintaining the original morphology.
AB - On the basis of the mixtures composed of CnTMAB/acids/TEOS/ water, the mesoporous materials with well-ordered hexagonal structures can be synthesized under acidic condition (pH < 1.0) with a careful control of the silica condensation. However, the induction period time for the formation of surfactant-silica precipitation varied with the employed acid source and decreased in the series: HNO3 < HBr < HCl < H 2SO4 at the same acid concentration. Increasing the acid concentration not only induced a fast precipitation rate, but also provoked more nuclei seeds formation and reduced the particle size of the mesoporous silica products. A proper aging time is also significant for getting the well-ordered mesoporous materials via acid route, and a longer aging time would induce a gradual decomposition of the mesostructures. For morphology, in acid synthetic medium, various interesting shell-like curved patterns on the surface of mesoporous silica particles were formed. The physical properties (such as d-spacing, pore size, BET surface area and porosity) of the calcined mesoporous silica are almost not affected by the nature of the acid source, but the pore size of the mesoporous materials can be tailored by varying the chain length of the surfactant. Adding the proper amount of ammonia solution for adjusting the pH value between 8-10 can improve the hexagonal mesostructures order of the mesoporous materials while maintaining the original morphology.
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U2 - 10.1002/jccs.200200127
DO - 10.1002/jccs.200200127
M3 - Article
AN - SCOPUS:0345834047
SN - 0009-4536
VL - 49
SP - 899
EP - 906
JO - Journal of the Chinese Chemical Society
JF - Journal of the Chinese Chemical Society
IS - 5
ER -