(765c) Characterizing the Temporal Evolution of Zeolite Crystallization in the Presence of Growth Modifiers

Rimer, J. D., University of Houston
Lupulescu, A. I., University of Houston

The unique properties of zeolite crystals have facilitated their integration in a variety of industrial processes ranging from ion exchange to catalysis [1], as well as emerging biofuel and photonic technologies. The inability to control single crystal growth often yields materials with sub-optimal performance that can be attributed to long, tortuous internal diffusion pathlengths and/or limited access to active sites due to small external porous surface areas. In order to address these challenges, we have applied a bio-inspired technique [2] to selectively tailor zeolite morphology and structure using molecules termed zeolite growth modifiers (ZGMs), which bind to specific crystal surfaces and mediate anisotropic growth rates [3,4]. We will discuss our efforts to characterize ZGM interactions with zeolite crystals at the early stages of nucleation and growth. Using techniques such as dynamic light scattering (DLS) and small angle X-ray scattering (SAXS), we have investigated the evolution of zeolite precursor nanoparticles (or pre-nuclei) [5] and small crystallites in the presence of ZGMs. These studies seek to elucidate fundamental mechanisms of zeolite crystallization towards the design of more versatile and facile synthesis techniques to enable greater control of the physicochemical properties of microporous materials.

[1] Corma, A., J. Catalysis. 216 (2003) 298-312.

[2] Rimer, J.D., An, Z., Zhu, Z., Lee, M.H., Goldfarb, D.S., Wesson, J.A., Ward, M.D., Science

330 (2010) 337-341.

[3] Lupulescu, A.I. and Rimer, J.D., Angew. Chem. Int. Ed. 51 (2012) 3345-3349.

[4] Lupulescu, A.I., Manjesh, K., Rimer, J.D., J. Am. Chem. Soc. 135 (2013) 6608-6617.

[5] Rimer, J. D., Vlachos, D. G., Lobo, R. F. J. Phys. Chem. B. 109 (2005) 12762.