Bio-Inspired Crystal Growth

One of nature's main strategies is growing crystals with improved mechanical and physical properties, usually CaCO3. This improvement (comparing to synthetic crystals), can be achieved by incorporation of organic molecules inside the inorganic crystals, which induce strains and cause cracks deflection. Inspired by nature, it was found that organic molecules, particularly amino acids and proteins, can be incorporated into the crystal lattice of synthetic calcite and induce anisotropic lattice distortions. Moreover, other functional materials such as semiconductors (ZnO and Cu2O) and hybrid perovskites also allow for such incorporation.

Figure 1. Synthesis of the ZnO-amino acids crystals and their band gap as a function of measured lattice strain along c-axis.

Similar to calcium carbonate system, such incorporation induces strains and causes the lattice parameters to change. In the case of ZnO and Cu2O, these strains also create a tunable change in the optical band-gap, which is directly dependent on the amount of molecules that were incorporated.

We also demonstrated and deciphered the mechanism of amino acids induced band gap change and improved stability in the case of hybrid perovskite methylammonium lead bromide.

Moreover, we reported on the formation of hybrid organic-metal composites via the incorporation of selected amino acids into the crystal lattice of single crystals of gold, which is this the first finding of incorporation of organic molecules within the gold lattice.

Figure 2. left. Schematics of gold crystal with incorporated amino acids. Left. The {111} diffraction peak from Au-control and Au-Ala samples before and after heating. a) Au-control before (black) and after (red) annealing at 250ºC for 2 h.



Lang A, Polishchuk I, Seknazi E, Feldmann J, Katsman A, Pokroy B. Bioinspired Molecular Bridging in a Hybrid Perovskite Leads to Enhanced Stability and Tunable PropertiesAdv Funct Mater 2020; DOI: 10.1002/adfm.202005136.

Polishchuk I, Bianco-Stein N, Lang A, Kurashvili M, Caspary Toroker M, Katsman A, Feldmann J and Pokroy B. Strong Band Gap Blueshift in Copper (I) Oxide Semiconductor via Bio-Inspired Route. Adv Funct Mater 2020; 30(13):1910405.

Mijowska S, Polishchuk I, Lang A, Seknazi E, Dejoie C, Fermani S, Falini G, Demitri N, Polentarutti M, Katsman A and Pokroy B. High amino acid lattice loading at non-ambient conditions causes changes in structure and expansion coefficient of calcite. Chem Mater 2020; 32(10):4205.

 Brif, A, Ankonina, G, Drathen, C, & Pokroy, B.  Bio‐Inspired Band Gap Engineering of Zinc Oxide by Intracrystalline Incorporation of Amino Acids. Adv Mater 201426(3), 477-481.‏

Borukhin S, Bloch L, Radlauer T, Hill AH, Fitch AN, Pokroy B. Screening the Incorporation of Amino Acids into an Inorganic Crystalline Host: the Case of Calcite. Adv Funct Mater 2012; 22:4216.

Weber E, Bloch L, Guth C, Fitch AN, Weiss IM and Pokroy B. Recombinant biomineralization fusion protein induces anisotropic lattice distortions in synthetic calcite. Chem Mat 2014; 26:4925. HIGHLIGHTED ON THE COVER.

Chen, L, Polishchuk, I, Weber, E, Fitch, A. N, & Pokroy, B. Hybrid gold single crystals incorporating amino acids. Crys Grow & Des 2016; 16(5), 2972-2978.