Thin films of noble-metal-based transition metal dichalcogenides, such as PtSe 2 , have attracted increasing attention due to their interesting layer-number dependent properties and application potential. While it is difficult to cleave bulk crystals down to mono- and few-layers, a range of growth techniques have been established producing material of varying quality and layer number. However, to date, no reliable high-throughput characterization to assess layer number exists. Here, we use top-down liquid phase exfoliation (LPE) coupled with centrifugation to produce PtSe 2 nanosheets of varying sizes and thicknesses with a low degree of basal plane defectiveness. Measurement of the dimensions by statistical atomic force microscopy allows us to quantitatively link information contained in optical spectra to the dimensions. For LPE nanosheets we establish metrics for lateral size and layer number based on extinction spectroscopy. Further, we compare the Raman s...

中文翻译：

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自上而下和自下而上的技术产生的PtSe 2层的光谱厚度和质量指标

诸如PtSe 2之类的贵金属基过渡金属二硫化氢薄膜由于其有趣的层数依赖性和应用潜力而受到越来越多的关注。尽管很难将大块晶体切割成单层和几层，但已建立了一系列生长技术，可生产质量和层数不同的材料。但是，迄今为止，尚不存在评估层数的可靠的高通量表征。在这里，我们使用自上而下的液相剥离（LPE）结合离心力，以生产出具有不同尺寸和厚度的PtSe 2纳米片，其基底平面缺陷程度低。通过统计原子力显微镜对尺寸进行测量，使我们能够将光谱中包含的信息定量链接到尺寸。对于LPE纳米片，我们基于消光光谱建立了横向尺寸和层数的度量。此外，我们比较了拉曼光谱。