The formation and growth of crystal nuclei of TPA-Silicalite-1 (aluminum free ZSM-5) from clear solns. using TEOS and silicic acid as silica sources were studied with small angle X-ray scattering (SAXS). Information was obtained on the size and shape of nanoscopic precursor particles of silicalite-1. The SAXS data can be interpreted assuming the presence of tablets of 4x2x1.3 nm up to 8x8x1.3 nm depending on the synthesis conditions. Starting solns. have been studied varying the silica source and the cations content (Sodium, Potassium and TPA). In each case well defined particle sizes are obsd. Although the nanoparticles differ in size, their shape is very similar and these data strengthen our hypothesis that TPA-Silicalite-1 formation is a nanoblock based aggregation mechanism rather than growth via monomer addn.
|Name||Studies in Surface Science and Catalysis|
|Conference||conference; 13th International Zeolite Conference, Montpellier, France, 8 - 13 July 2001; 2001-07-08; 2001-07-13|
|Period||8/07/01 → 13/07/01|
|Other||13th International Zeolite Conference, Montpellier, France, 8 - 13 July 2001|