Ultra-small crystals, synthesis

Naturally-produced zeolites often far surpass those made in the laboratory in terms of their large size and sheer beauty. However, the time-frame of nature s synthesis procedure is measured in millennia - clearly not an option for even the most patient scientist. Hence it is up to the scientist to use his ingenuity in creating methods to prepare ultra-large or ultra-small crystals in the laboratory. 

Excellent studies have been performed on the synthesis of ultra-small crystals of MFI-type zeolite [59,60]. In particular the preparation of suspensions of colloidal silicalite-1 crystals (less than 100 nm) with a narrow particle-size distribution have been extensively studied. 

In the case of explosive nucleation, the nutrient pool is rapidly depleted and further substantial crystal growth is avoided. Thus ultra-small crystals, down to 30 nm, with a small crystal size distribution can be obtained. Generally, monomeric reagents and low synthesis temperatures are used for preparing ultrasmall crystals. 

Coker, E. N. and Jansen, J. C. (1998) Approaches for the synthesis of ultra-large and ultra-small zeolite crystals. In Molecular Sieves. (H. G. Karge and J. Weitkamp, eds.). Springer, Berlin Germany and New York, N.Y. pp. 121-155. 

Approaches for the Synthesis of Ultra-Large and Ultra-Small Zeolite Crystals... 

Coker EN, Jansen JC (1998) Approaches for the Synthesis of Ultra-Large and Ultra-Small Zeolite Crystals. 1 121-155... 

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