The University of British Columbia, Department of Materials Engineering, Vancouver, B.C., V6T1Z4, Canada.
Nanotechnology. 2017 Jul 14;28(28):285301. doi: 10.1088/1361-6528/aa76ae. Epub 2017 Jun 2.
We report uniform layer-by-layer sublimation of black phosphorus under heating below 600 K. The uniformity and crystallinity of BP samples after thermal thinning were confirmed by Raman spectra and Raman mapping. The sublimation rate of BP was around 0.18 nm min at 500 K and 1.15 nm min at 550 K. Both room and high temperature Raman peak intensity ratio [Formula: see text] as functions of BP thickness were established for in situ thickness determination and control. Uniform and crystalline 2 to 4-layer BP flakes with areas from 10 to 1000 μm were prepared with this method. No micron scale defects were observed. The sublimation thinning method was shown to be a controllable and scalable approach to prepare high-quality few-layer black phosphorus.
我们报告了在低于 600 K 的加热条件下，黑磷的均匀逐层升华。通过拉曼光谱和拉曼映射证实了热变薄后 BP 样品的均匀性和结晶度。在 500 K 时，BP 的升华速率约为 0.18nm min，在 550 K 时，BP 的升华速率约为 1.15nm min。建立了室温及高温下拉曼峰强度比[Formula: see text]随 BP 厚度变化的关系，用于原位厚度测定和控制。用这种方法制备了面积从 10 到 1000 μm 的均匀、结晶的 2 到 4 层 BP 薄片，没有观察到微米级缺陷。升华减薄法是一种可控且可扩展的制备高质量少层黑磷的方法。
