The fabrication of metal-oxide-pillared clay by a simple, environmentally friendly method is reported. The interlayer space within the clay (vermiculite, VMT) is first modified, followed by the intercalation of metal alkoxides dissolved in supercritical CO2 (see Figure), which are then hydrolyzed. Large electrostatic charges on VMT help resist delamination during intercalation and maintain ordered structures after calcination. Basal spacing and porosity are controllable by the intercalation time.