Nguyen Dinh-Tuan, Ting Hsiang-An, Su Yen-Hsun, Hofmann Mario, Hsieh Ya-Ping
Department of Materials Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
Department of Mechanical Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan.
Nanomaterials (Basel). 2021 Feb 28;11(3):601. doi: 10.3390/nano11030601.
The success of van-der-Waals electronics, which combine large-scale-deposition capabilities with high device performance, relies on the efficient production of suitable 2D materials. Shear exfoliation of 2D materials' flakes from bulk sources can generate 2D materials with low amounts of defects, but the production yield has been limited below industry requirements. Here, we introduce additive-assisted exfoliation (AAE) as an approach to significantly increase the efficiency of shear exfoliation and produce an exfoliation yield of 30%. By introducing micrometer-sized particles that do not exfoliate, the gap between rotor and stator was dynamically reduced to increase the achievable shear rate. This enhancement was applied to WS and MoS production, which represent two of the most promising 2D transition-metal dichalcogenides. Spectroscopic characterization and cascade centrifugation reveal a consistent and significant increase in 2D material concentrations across all thickness ranges. Thus, the produced WS films exhibit high thickness uniformity in the nanometer-scale and can open up new routes for 2D materials production towards future applications.
范德华电子学将大规模沉积能力与高器件性能相结合，其成功依赖于合适二维材料的高效生产。从块状源对二维材料薄片进行剪切剥离可生成缺陷数量少的二维材料，但产量一直低于行业要求。在此，我们引入添加剂辅助剥离（AAE）方法，以显著提高剪切剥离效率并实现30%的剥离产率。通过引入不发生剥离的微米级颗粒，动态减小转子与定子之间的间隙以提高可实现的剪切速率。这种增强作用应用于WS和MoS的生产，它们是两种最具前景的二维过渡金属二硫属化物。光谱表征和级联离心显示，在所有厚度范围内二维材料浓度均持续且显著增加。因此，所制备的WS薄膜在纳米尺度上具有高度的厚度均匀性，并可为二维材料生产通向未来应用开辟新途径。
