動態光散射研究溶液中二維材料之行為

Dynamic Light Scattering for the Investigation of 2D Materials Behavior in Solution

張晏嘉(Yeh-Chia Chang)

指導教授 ： 謝馬利歐

國立臺灣大學/理學院/應用物理研究所/碩士(2022年)

https://doi.org/10.6342/NTU202202272

摘要

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。

關鍵字

粒徑分析 ； 動態光散射 ； 曝光時間相關光譜 ； 圖像功率光譜 ； 流動

並列摘要

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.

並列關鍵字

Particle sizing ； Dynamic light scattering ； Exposure Time Dependent Spectrum ； Image power spectrum ； Flowing effect iv

參考文獻

[1] K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos, I. V. Grigorieva, and A. A. Firsov. Electric field effect in atomically thin carbon films. Science, 306(5696):666–669, 2004.

[2] K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, M. I. Katsnelson, I. V. Grigorieva, S. V. Dubonos, and A. A. Firsov. Two-dimensional gas of massless dirac fermions in graphene. Nature, 438:197–200, 2005.

[3] Changgu Lee, Xiaoding Wei, Jeffrey W. Kysar, and James Hone. Measurement of the elastic properties and intrinsic strength of monolayer graphene. Science, 321(5887):385–388, 2008.

[4] A.A. Balandin, S. Ghosh, W. Bao, I. Calizo, D. Teweldebrhan, F. Miao, and C. N. Lau. Superior thermal conductivity of single-layer graphene. Nano Lett, 8:902, 2008.

[5] Hua-Ding Song, Peng-Fei Zhu, Jingzhi Fang, Ziqi Zhou, Huai Yang, Kaiyou Wang, Jingbo Li, Dapeng Yu, Zhongming Wei, and Zhi-Min Liao. Anomalous hall effect in graphene coupled to a layered magnetic semiconductor. Phys. Rev. B, 103:125304, Mar 2021.