摘要
由於石墨烯良好的導熱性、透光性及導電性。因此，其為目前最有機會取代傳統金屬氧化物，作為軟性電子元件及顯示器的材料之一。而石墨烯平面熱傳導係數 (2000~5300 Wm-1K-1) 以及內部載子移動率 (2 × 105 cm2V-1s-1) 都相當的高。而這些光電熱特性則因石墨烯生產時的層數有著極大的影響。然而，目前業界仍然缺少了，可大量生產高品質且低成本石墨烯的技術。而電化學剝離石墨烯生產技術，則提供了一個由便宜的石墨原料生產大量高品質石墨烯的技術。由此技術生產出來的石墨烯大多為雙層或多層石墨烯，而它們剝離下來的尺寸可達到數十微米等級。由拉曼光譜分析可知，電化學剝離石墨烯的品質優於傳統之氧化還原石墨烯。利用轉移電化學剝離石墨烯至可饒透明基材上可製造出可饒透明導電膜。而透過這樣卷對卷的生產方式，則可以很容易地製造出大面積的可饒透明石墨烯導電膜。而其片電阻及熱電特性因數則由其層數所影響，而石墨烯的層數(厚度)則由其穿透度來定義。由紫外光-可見光光譜儀量測其穿透度可達85 %。
關鍵詞：電化學剝離石墨烯、片電阻、卷對眷製造技術、熱電特性因數
Abstract
Graphene is a promising candidate for replacing some metal oxide-based materials. Due to its high conductivity and flexability, it can fabricated into transparent and supple conducting electrodes used in displays and electronic devices. Its in-plane thermal conductivity (2000~5300 Wm-1K-1) and intrinsic carrier mobility (2 × 105 cm2V-1s-1) are extremely high, depending on the size of graphene flake and number of graphene layers, as well as its quality. However, currently there is still no good method to provide high-quality, low-cost graphene in large quantities. Electrochemically exfoliated graphene enables the fabrication of massive graphene sheets in an ink form using artificial graphite as the starting material. This product is mainly composed of bi-layer and multi-layered graphene. Its lateral size can reach over ten μm, and the quality as measured by Raman spectroscopy has been shown to be higher than that of the reduced graphene oxide. The transparent and flexible conducting films made of the electrochemically exfoliated graphene can be simply transferred from the graphene ink onto any flexible and transparent substrate, such as polyethylene terephthalate, which is easy to scale up for large-area deposition via roll-to-roll fabrication. The sheet resistance and thermoelectric figures of merit, ZT of the electrochemically exfoliated graphene, have been measured as a function of its thickness as specified by its transmittance (85%), determined by a UV-Vis spectrometer, and the thermal conductivity can be determined through its thermoelectric properties.
Keywords: Electrochemically Exfoliated Graphene, Sheet Resistance, Roll-to-roll Fabrication, Thermoelectric Figures of Merit