Sol–gel synthesis of monolithic molybdenum oxide aerogels and xerogels

Abstract

Monolithic molybdenum trioxide aerogels and xerogels have been synthesized by the sol–gel method. A three-dimensional molybdenum oxide network is achieved by suppressing Mo=O bond formation through a ligand exchange process. IR spectroscopy is used to characterize the bond formations during gelation, aging, and drying of the gels. The as-prepared aerogels are low density (0.15–0.30 g cm^–3) amorphous materials with surface areas of 150–180 m² g^–1 . Upon heating to 400 °C, the amorphous solids crystallize to orthorhombic MoO₃ .

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