2D layered materials, such as gallium selenide (GaSe), if exfoliated adjustably, exhibit several excellent properties, offering great potential for diverse uses. Herein, bulk GaSe is exfoliated by a novel temperature-adjustment bath-ultrasonic method. The obtained single to few layers of high-quality GaSe nanosheets are deposited on a silicon/silicon dioxide (Si/SiO₂) wafer and characterized by different methods to demonstrate the bath-temperature non-monotonic effect on the quality of nanoflakes. The optimal bath-ultrasonic experimental scheme of GaSe nanosheet preparation is proposed. The adjustment of temperature shows effective control over the micromorphology of the exfoliated GaSe material, especially the thickness of the nanosheets. Through atomic force microscopy (AFM) characterization of all samples, it can be observed that the nanosheets exhibit a uniform thickness, which means that this novel temperature-adjustment exfoliation method is of general significance. It is found that the bath temperature of the ultrasonic process plays an important role in the synthesis of samples. A reasonable exfoliation mechanism of 2D ultrathin nanosheets is proposed and the energetics of the bath-ultrasonic process are discussed.

中文翻译：

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通过温度调节浴-超声波处理将大块硒化镓简单剥离成单层/几层

二维层状材料，如硒化镓 (GaSe)，如果可调节剥离，则表现出多种优异性能，为各种用途提供巨大潜力。在这里，块状 GaSe 是通过一种新的温度调节浴超声波方法剥离的。将获得的单层或几层高质量 GaSe 纳米片沉积在硅/二氧化硅 (Si/SiO ₂) 晶片，并通过不同的方法表征，以证明浴温对纳米薄片质量的非单调影响。提出了GaSe纳米片制备的最佳浴-超声实验方案。温度的调节显示了对剥离的 GaSe 材料的微观形貌的有效控制，尤其是纳米片的厚度。通过所有样品的原子力显微镜（AFM）表征，可以观察到纳米片表现出均匀的厚度，这意味着这种新型的温度调节剥离方法具有普遍意义。发现超声波工艺的浴温在样品合成中起着重要作用。