Generation of voids in the alkyl layers of an alkyl derivative of boehmite by heat treatment and adsorption behavior of the voids

The solvothermal reaction of aluminum isopropoxide in 1-decanol yielded the decyl derivative of boehmite [AlO(OH)(1−X)(OC10H21)X]. This product belongs to a class of intercalation compounds where the guest moieties are covalently bonded to the host inorganic (boehmite) layers. In this work, the alkyl chains in the boehmite layers were partially removed by heat treatment in an He flow. X-ray diffraction (XRD), thermogravimeter (TG), and N2 adsorption measurement showed that the voids surrounded by the alkyl chains were generated by the heat treatment. When the decyl derivative of boehmite was heated at 310 °C for 3 h in the He flow, the voids had the largest volume, but prolonged heat treatment resulted in partial collapse of the boehmite layers causing a smaller void volume.