Nanocasting synthesis of ordered mesoporous alumina with crystalline walls: influence of aluminium precursors and filling times

摘要

The influence of aluminum precursors and filling times on the nanocasting synthesis of ordered crystalline mesoporous alumina molecular sieve with CMK-3 as an exotemplate was investigated. With the aid of nitrogen physisorption, XRD and TEM characterizations, we found that neither aluminum alkoxide nor boehmite sol was suited to be incorporated into the template pores to achieve stable alumina frameworks under our experimental conditions. The employment of aluminum nitrate as a precursor and then in situ precipitation into the template pores led to stable alumina frameworks after 4 repeated filling cycles. Direct decomposition of alumina nitrate can also yield ordered mesoporous alumina but with poor crystallized walls.