A high-pressure synthesis of hydrothermally stable periodic mesoporous crystalline aluminosilica materials†
Abstract
We report a synthetic route to mesoporous crystalline aluminosilica materials using high pressure and temperature. In the first step a large-pore periodic mesoporous aluminosilica SBA-15 material was filled with carbon at ambient pressure. We observed that crystallization of the pore walls of periodic mesoporous aluminosilica/carbon composites occurred at 2 GPa and a temperature of 650 °C without significant distortion of the mesostructure. Combustive removal of carbon from the crystallized composite in air led to the formation of periodic mesoporous crystalline aluminosilica materials. These materials are steam stable and are resistant to shrinkage under the harsh conditions of hydrothermal treatment at 800 °C.