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arXiv · 2009.04033

Unzipping chemical bond of non-layered bulk structures to form ultrathin nanocrystals

Liangxu Lin·Chang Wu·Juntong Huang·Andrew Nattestad·Jun Chen·Gordon G. Wallace·Shaowei Zhang
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Abstract

The rich electronic and band structures of monolayered crystals distinguished from their layered bulk counterparts offer versatile physical/chemical properties and applications.1-5 Their fabrications, particularly the top-down "exfoliations", are successful promised by the weak Van der Waals force between monolayers.6-9 Differentially, un-zipping ultra-thin crystals (e.g. with only one layer of crystal plane) from non-layered structures is highly challenging due to the strong chemical bond between planes and atoms. Alterative finely controlled growth of these ultra-thin materials is not really successful. This work demonstrates how a technique can be used to unzip and disintegrate ultra-thin crystal plane (e.g. monolayered nanocrystals and nanosheets) from bulk non-layered structures (ZnO, alpha/belta-MnO2, TiO2, alpha-TiB2), and present how the basic optical properties changed to distinguish from their bulk phases. The work here gives a strong tool kit to various novel 2D non-layered nanomaterials, providing significant contributions to the family of two-dimensional materials, potentially paving the way for various practical applications.

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Liangxu Lin, Chang Wu, Juntong Huang, Andrew Nattestad, Jun Chen, Gordon G. Wallace, Shaowei Zhang. 2020-09-08. Unzipping chemical bond of non-layered bulk structures to form ultrathin nanocrystals. https://doi.org/10.1016/j.matt.2020.12.023

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