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arXiv · 2206.13706

Chiral Assemblies of Pinwheel Superlattices on Substrates

Shan Zhou·Jiahui Li·Jun Lu·Haihua Liu·Ji-Young Kim·Ahyoung Kim·Lehan Yao·Chang Liu·Chang Qian·Zachary D. Hood·Wenxiang Chen·Thomas E. Gage·Ilke Arslan·Alex Travesset·Kai Sun·Nicholas A. Kotov·Qian Chen
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Abstract

The unique topology and physics of chiral superlattices make their self-assembly from nanoparticles a holy grail for (meta)materials. Here we show that tetrahedral gold nanoparticles can spontaneously transform from a perovskite-like low-density phase with corner-to-corner connections into pinwheel assemblies with corner-to-edge connections and denser packing. While the corner-sharing assemblies are achiral, pinwheel superlattices become strongly mirror-asymmetric on solid substrates as demonstrated by chirality measures. Liquid-phase transmission electron microscopy and computational models show that van der Waals and electrostatic interactions between nanoparticles control thermodynamic equilibrium. Variable corner-to-edge connections among tetrahedra enable fine-tuning of chirality. The domains of the bilayer superlattices display strong chiroptical activity identified by photon-induced near-field electron microscopy and finite-difference time-domain simulations. The simplicity and versatility of the substrate-supported chiral superlattices facilitate manufacturing of metastructured coatings with unusual optical, mechanical and electronic characteristics.

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Shan Zhou, Jiahui Li, Jun Lu, Haihua Liu, Ji-Young Kim, Ahyoung Kim, Lehan Yao, Chang Liu, Chang Qian, Zachary D. Hood, Wenxiang Chen, Thomas E. Gage, Ilke Arslan, Alex Travesset, Kai Sun, Nicholas A. Kotov, Qian Chen. 2022-06-28. Chiral Assemblies of Pinwheel Superlattices on Substrates. https://doi.org/10.1038/s41586-022-05384-8

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