Sodium fluoride (NaF) has been found to be an activation agent in exfoliating a hexagonal boron nitride (hBN) platelet, using a solvent free method. The procedure was carried out by enhancing the intercalation of ferric chloride (FeCl₃) in an intermediate step, up to 330 °C, followed by removal of the by-product at room temperature. In this research, five additional common salts, including lithium fluoride, potassium fluoride, lithium chloride, sodium chloride, and potassium chloride, were examined and compared to NaF for their effectiveness in achieving maximum exfoliation of commercially available sub-micron-sized hBN. It was found that all fluoride and chloride salts significantly activated the intercalation of FeCl₃ into this hBN. Analyses and characterization by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and Raman spectroscopy revealed NaCl to be one of the most effective agents without further heat treatment and the least expensive salt for the intercalation reaction and exfoliation process. The synthetic route of this solvent free method is straightforward, achieving yields of 89% or higher, making it suitable for large scale production.

中文翻译：

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使用无溶剂方法对亚微米六方氮化硼进行高产率剥离


氟化钠 （NaF） 已被发现是使用无溶剂方法去除六方氮化硼 （hBN） 片状的活化剂。该程序是通过在中间步骤中增强三氯化铁 （FeCl₃） 的插层来实现的，最高可达 330 °C，然后在室温下去除副产物。在这项研究中，检查了另外五种常见盐，包括氟化锂、氟化钾、氯化锂、氯化钠和氯化钾，并与 NaF 进行了比较，以了解它们在最大限度地去除市售亚微米大小的 hBN 方面的有效性。结果发现，所有氟化物盐和氯盐都显著激活了 FeCl₃ 嵌入到该 hBN 中。通过 X 射线衍射、扫描电子显微镜、傅里叶变换红外光谱和拉曼光谱进行分析和表征表明，NaCl 是无需进一步热处理的最有效试剂之一，也是插层反应和剥离过程最便宜的盐。这种无溶剂方法的合成路线简单明了，产量达到 89% 或更高，使其适用于大规模生产。