二硫化鉬之化學修飾

Chemical Functionalization of Molybdenum Disulfides

劉威伸(Liu, Wei Shen)

指導教授 ： 李奕賢

國立清華大學/工學院/材料科學工程學系/碩士(2015年)

摘要

本研究藉由表面修飾來改變二硫化鉬的光學和電學特性，利用羅丹明B(Rhodamin B, RhB)和二甲基甲醯胺(DMF)修飾二硫化鉬有效地達到與二硫化鉬的電荷轉移，並探討RhB和DMF的電荷轉移機制。利用拉曼光譜(Raman)和光致螢光光譜(Photoluminescence)檢視RhB和DMF修飾對二硫化鉬造成P型摻雜或和型摻雜的效果；利用原子力顯微鏡(Atomic Force Microscopy, AFM)量測觀察分子分布的均勻性和厚度，最後將二硫化鉬製成之元件做電性量測分析。根據RhB和DMF的分子結構和官能基提出電荷轉移的機制，此研究結果顯示RhB造成二硫化鉬P型摻雜，DMF則是造成二硫化鉬N型摻雜，並且提供電性量測直接證明化學修飾後有P型和N型摻雜的趨勢，本研究利用RhB和DMF修飾的方法對於改變二硫化鉬之電子元件特性的改變相當有潛力。

關鍵字

二硫化鉬 ； 化學修飾 ； 羅丹明B ； 二甲基甲醯胺 ； P型 ； N型

並列摘要

Our research dedicate to chemical functionalization and effect of Raman and PL that molecular induce, we conclude mechanism of rhodamine B and dimethylformamide, by chemical functionalization, electrons can transfer to molybdenum disulfide and change its optical and electric properties. We confirm that molecular cause molybdenum disulfide what effect is induced by Raman and Photoluminescence, observe distribution and uniformity of molecular by AFM. Finally, we measure device that are made of molybdenum disulfide and show that molecular functionalization change electrical properties of molybdenum disulfide indeed. According to results of Raman and PL, we can discern what effect molecular cause and conclude mechanism of molecular. Our research shows rhodamine B that has benzene and electron-withdrawing can cause molybdenum disulfide p-doping, however, dimethylformamide contains electron-donating and causes molybdenum disulfide n-doping. Our research offers results of chemical functionalization that we can refer to change electrical properties of molybdenum disulfide in future.

並列關鍵字

Molybdenum disulfide ； functionalization ； Rhodamine B ； Dimethylformamide ； p doping ； n doping

參考文獻

[1] Novoselov, K. S., et al. "Two-dimensional atomic crystals." Proceedings of the National Academy of Sciences of the United States of America 102.30 (2005): 10451-10453.

[2] Dean, C. R., et al. "Boron nitride substrates for high-quality graphene electronics." Nature nanotechnology 5.10 (2010): 722-726.

[3] Pacile, D., et al. "The two-dimensional phase of boron nitride: Few-atomic-layer sheets and suspended membranes." Applied Physics Letters 92.13 (2008): 133107.

[4] Elias, D. C., et al. "Dirac cones reshaped by interaction effects in suspended graphene." Nature Physics 7.9 (2011): 701-704.

[5] Lin, Ming-Wei, et al. "Room-temperature high on/off ratio in suspended graphene nanoribbon field-effect transistors." Nanotechnology 22.26 (2011): 265201.