(28i) Biomimetic Crystal Growth for Programmable Separation and Chiroptical Properties

Non-classical growth mechanisms are a hallmark of biomimetic crystal growth [1]. Recently, bio-inspired growth has resulted in unique structural morphologies with novel physical and chemical properties. However, these growth mechanisms are often investigated as an after-thought, rather than a set of rules which can be broken at will to create the desired structures/properties. Here, I will describe two studies where informed intervention at the early stages of crystal growth lead to (i) record-breaking membrane performance and, (ii) hierarchically complex chiral micro-particles. Firstly, I will describe the engineering of one-dimensional defects in two-dimensional zeolite nanosheets as an extendable model system [2]. This study demonstrates the impact of atomic scale defects on enhanced macro-scale separation performance for xylene mixtures [3,4]. Secondly, I will demonstrate the art of navigating the free-energy landscape during the self-assembly of gold-cysteine colloids with programmable chiroptical properties [5]. Both these studies leverage the synergistic application of state-of-the-art characterization, computational and mathematical tools across multiple length scales towards a unified understanding of non-classical growth.

References
[1] J. J. De Yoreo et al. Crystallization by particle attachment in synthetic, biogenic, and geologic environments. Science, 349, aaa6760 (2015).
[2] Prashant Kumar, Kumar Varoon Agrawal, Michael Tsapatsis, K Andre Mkhoyan. Quantification of thickness and wrinkling of exfoliated two-dimensional zeolite nanosheets. Nature Communications, 6, 7128 (2015).
[3] Prashant Kumar, Dae Woo Kim, Neel Rangnekar, Hao Xu, Evgenii Fetisov et. al. One-dimensional intergrowths in two-dimensional zeolite nanosheets and their effect on ultra-selective transport. Nature Materials, 19, 443–449 (2020).
[4] Mi Young Jeon*, Donghun Kim*, Prashant Kumar*, Pyung Soo Lee*, Neel Rangnekar, Peng Bai et. al. Ultra-selective high-flux membranes from directly synthesized high aspect ratio zeolite nanosheets. Nature, 543, 690-694 (2017) * equal contribution.
[5] Wenfeng Jiang, Zhibei Zhu, Prashant Kumar et.al. Emergence of complexity in Hierarchically Organized Chiral Particles. Science, eaaz7949 (2020).