TY - JOUR
T1 - Synthesis of nanostructured mesoporous zirconia using CTMABr-ZrOCl2.8H2O systems : Kinetic study of synthesis mechanism
AU - Blin, Jean-Luc
AU - Flamant, Renald
AU - Su, Bao-Lian
PY - 2001
Y1 - 2001
N2 - A systematic kinetic study of mesoporous zirconia formation has been performed in order to optimize the synthesis conditions without addition of structure stabilizing agents such as sulfate or phosphate anions. We have investigated in particular the effect of synthesis time and temperature. On the basis of TEM, SEM, XRD and N2 adsorption-desorption results, a synthesis mechanism has been proposed. It is observed that at low temperature or for short durations at higher temperatures, the obtained materials are first supermicroporous, then if hydrothermal treatment is prolonged, a breakdown of the walls separating adjacent pores allows the transformation to mesopores. The obtained materials have a uniform pore size and their surface can reach 300 m2/g. The channel array is, at least part of samples, wormlike. However, if hydrothermal treatment is performed at too high temperature or for too long durations, mesoporous compounds are no longer obtained, but thermodynamically more stable crystalline zirconium oxides with very low specific surface area, namely the tetragonal and monoclinic forms, are the final phases.
AB - A systematic kinetic study of mesoporous zirconia formation has been performed in order to optimize the synthesis conditions without addition of structure stabilizing agents such as sulfate or phosphate anions. We have investigated in particular the effect of synthesis time and temperature. On the basis of TEM, SEM, XRD and N2 adsorption-desorption results, a synthesis mechanism has been proposed. It is observed that at low temperature or for short durations at higher temperatures, the obtained materials are first supermicroporous, then if hydrothermal treatment is prolonged, a breakdown of the walls separating adjacent pores allows the transformation to mesopores. The obtained materials have a uniform pore size and their surface can reach 300 m2/g. The channel array is, at least part of samples, wormlike. However, if hydrothermal treatment is performed at too high temperature or for too long durations, mesoporous compounds are no longer obtained, but thermodynamically more stable crystalline zirconium oxides with very low specific surface area, namely the tetragonal and monoclinic forms, are the final phases.
KW - synthesis mechanism
KW - thermal stability
KW - ionic surfactant
KW - CTMABr-ZrOCl<sub>2</sub>.8H<sub>2</sub>O
KW - mesoporous ZrO<sub>2</sub>
M3 - Article
VL - 3
SP - 959
EP - 972
JO - International Journal of Inorganic Materials
JF - International Journal of Inorganic Materials
ER -