Universal mechanical exfoliation of large-area 2D crystals
Universal mechanical exfoliation of large-area 2D crystals
复制标题
大面积二维晶体的通用机械剥离
DOI：
10.1038/s41467-020-16266-w
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发表时间：
2020-05-15
影响因子：
16.6
通讯作者：
Gao, Hong-Jun
中科院分区：
文献类型：
--
作者：
Huang, Yuan;Pan, Yu-Hao;Gao, Hong-Jun
二维材料为探索原子薄晶体中产生的现象提供了非凡的机会。从第一次分离石墨烯开始，机械剥离一直是提供高质量二维材料的关键，但尽管有所改进，但在产量、横向尺寸和污染方面仍然受到限制。在这里，我们介绍了一种无公害，一步和通用的金辅助机械剥离方法，并通过分离40种类型的单晶单层，包括元素二维晶体，金属二硫族化合物，磁铁和超导体，证明了其有效性。电子显微镜、光谱学和电输运的无转移测量表明，它们大多数都是毫米级的高质量材料。制备了大型悬浮二维晶体和异质结。晶体和衬底之间增强的附着力使这种有效的剥离成为可能，为此，我们确定了一种金辅助剥离方法，该方法支持生产大面积单层的通用途径，从而支持对二维材料的基本性质和潜在应用的研究。
Two-dimensional materials provide extraordinary opportunities for exploring phenomena arising in atomically thin crystals. Beginning with the first isolation of graphene, mechanical exfoliation has been a key to provide high-quality two-dimensional materials, but despite improvements it is still limited in yield, lateral size and contamination. Here we introduce a contamination-free, one-step and universal Au-assisted mechanical exfoliation method and demonstrate its effectiveness by isolating 40 types of single-crystalline monolayers, including elemental two-dimensional crystals, metal-dichalcogenides, magnets and superconductors. Most of them are of millimeter-size and high-quality, as shown by transfer-free measurements of electron microscopy, photo spectroscopies and electrical transport. Large suspended two-dimensional crystals and heterojunctions were also prepared with high-yield. Enhanced adhesion between the crystals and the substrates enables such efficient exfoliation, for which we identify a gold-assisted exfoliation method that underpins a universal route for producing large-area monolayers and thus supports studies of fundamental properties and potential application of two-dimensional materials.