動態光散射研究溶液中二維材料之行為

Abstract

二維材料已在電子學、光學和生命科學等眾多應用領域中展現出巨大的前景。為了瞭解它們的潛力，需要一種強大且可擴增的生產方法。液相剝離法讓我們在二維材料製造中可調節橫向尺寸和厚度。然而，由於特徵方面的挑戰，使我們對潛在機制和參數影響的理解有限。我們在這裡利用近場動態光散射技術對溶液中二維材料的形態進行原位測量。我們實現了一種曝光時間相關光譜的演算法，該演算法使用高速感光耦合元件分析光斑快速變化中對角度的依賴性。通過提取相關的時間常數，提供了對粒徑的估計。實驗結果已用標準粒徑校準，顯示出良好的預測能力。我們將該系統應用於表徵各種流體動力學條件下的二維材料。

Two-dimensional materials have shown great promise towards a multitude of applications, such as electronics, photonics, and life sciences. To realize their potential, a powerful and scalable production method is required. Liquid exfoliation allows fabrication of 2D materials with adjustable lateral dimension and thickness. However, limited understanding of the underlying mechanism and the impact of process parameters exists due to challenges in characterization. We here utilize a nearfield Dynamic Light Scattering (DLS) technique to conduct in-situ measurements of the 2D materials morphology within solution. We implement an Exposure Time Dependent Spectrum (ETDS) algorithm that analyzes the angle dependence in the fast variation of light speckles using a high-speed CCD. Through extraction of the correlated time constant, a robust estimate of the particle size is produced. The experimental DLS results were calibrated with particle size standards and show good predicting ability. We apply the system to characterizing 2D materials in various fluid dynamic conditions.