利用同步輻射光電子能譜顯微技術進行凡德瓦材料電子結構研究

Study of the Electronic Structure of the van der Waals Materials by Synchrotron Radiation Photoelectron Spectromicroscopy

許紘瑋(Hung Wei Shiu) ； 張羅嶽(Lo Yueh Chang) ； 陳家浩(Chia-Hao Chen)

《化學》 76卷2期 (2018/06) Pp. 147-154

https://doi.org/10.6623/chem.201806_76(2).004

摘要

隨著石墨烯的發展，二維材料受到廣泛的重視。這些材料的共通點是共價鍵層狀結構，以凡德瓦(van der Waals; vdW)力將其束縛為塊材，因此也稱為凡德瓦材料。凡德瓦材料包含了最單純的由單一碳元素構成的石墨烯、過渡金屬的硫族化合物(transition metal dichalcogenides; TMDs)、過渡金屬氧化物和拓墣絕緣體等，含跨了多樣化的電子結構及物理性質。也因此凡德瓦材料具有廣泛的應用潛力。但是以目前而言，絕大多數的高結晶性二維材料，面積大小都在數微米到數十微米左右，且由於僅單原子/單分子層厚度，大大增加了研究其基本性質的困難度。本文即針對同步輻射光電子能譜顯微術在單層凡德瓦材料異質結構及單層凡德瓦材料與基材的交互作用等方面的應用作一簡單的報導，利用同步輻射相關能譜顯微技術，系統性的探討單層凡德瓦材料的本徵及其異質介面的物理化學結構，以及單層凡德瓦材料與基材的交互作用等，以期深入了解二維凡德瓦材料多樣化的性質，並對其後續的元件應用有所助益。

關鍵字

凡德瓦材料 ； 石墨烯 ； 過渡金屬硫族化合物 ； 同步輻射光電子能譜顯微術 ； 異質介面

並列摘要

With the progress of graphene researches, the graphene related two-dimensional materials attracted wide attention in recent years. The common feature of these materials is that the bulk 3D crystals are stacked structures, they involve van der Waals (van der Waals, vdW) interaction between adjacent sheets with strong covalent bonding within each sheet. Due to their nature of vdW interaction, these are also known as the van der Waals materials. Van der Waals materials span a wide range of materials from the graphene with simplest structure, to transition metal chalcogenides, transition metal oxides and topological insulators, etc., containing a wide variety of electronic structures and physical properties. VdW materials therefore have a wide range of potential applications. However, the size of most high quality crystalline vdW materials is at most in the range of several tens of μm^2 with single atomic or molecular thickness. This fact largely increases the difficulty to study the fundamental properties of such materials. In this article, I will briefly introduce the recent results by using synchrotron radiation based scanning photoelectron spectromicroscopy, to study the electronic structure of the single-layer vdW heterostructure and the interaction between the vdW material and the substrate.

並列關鍵字

Van der Waals material ； Graphene ； Transition metal dichalcogenides ； Synchrotron radiation based scanning photoelectron spectromicroscopy ； Heterostructure