在低壓系統以過渡金屬催化製備石墨烯之生長機制

石墨烯(Graphene)為碳原子排列成六角型蜂巢晶格的二維網格，具有優越的光學、電學與機械特性，使得僅有原子級厚度的石墨烯提高了在導電薄膜方面的應用價值。本研究利用過渡金屬銅、鎳元素與石墨的混合粉末於低壓系統下，加熱至熔融狀，再利用冷卻階段改變合金對碳固溶度，使得碳析出於金屬表面，並以平面sp2鍵結形成石墨薄層；再利用酸蝕技術將合金塊錠表面之石墨薄層轉移至玻璃基板上。主要探討於相同合金配比下，改變碳含量對於形成sp2鍵結之石墨薄層的影響，藉由形貌與塊錠剖面的觀察解釋石墨薄層生長機制。石墨薄層生長機制為固溶再析出。首先，由合金樹枝狀晶析出之平面石墨排列於合金表面，隨著石墨添加量的增加，由於碳-碳鍵結能比鎳-碳或銅-碳鍵結能大，使得持續析出的石墨薄層以片狀相互拼結，因而達到連續態之石墨薄層；當石墨含量提高，大量的石墨偏析導致團聚現象明顯，增加了析出石墨薄層排列之異向性，表面出現了角錐狀之形貌，形貌出現不平整的片狀堆疊。此外，由於合金與石墨之間的熱膨脹係數之差異，導致在進行冷卻階段時產生熱應力集中的現象，形貌出現了隆起狀，稱此為皺摺。

關鍵字

石墨烯；液相催化

並列摘要

Graphene is a plane of carbon atoms that resembles to honeycomb lattice as chicken wire. Not only is it the excellent electronic and optical properties, it is also extremely stiff and strong. Those remarkable properties make graphene at the atomic scale become being widely applied such as the conductive film. In present work, we report a method to fabricate the graphite film on the transition metal alloy in vacuum system. Graphite will precipitate through the cooling process and assemble to sp2 bonding to form the continuous graphite film. To transform the substrate, use acid etching to transform glass from the alloy. The mechanism of graphene growth combined with diffusion and precipitation. The precipitation of planar graphite film will connect by itself. Moreover, the more graphite contenting, the rough of the microscopes were. Wrinkles were found within the graphite film due to the different coefficient of thermal expansion between alloy and graphite.

並列關鍵字

graphene ； liquid-phase catalysis

參考文獻

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國際替代計量

在低壓系統以過渡金屬催化製備石墨烯之生長機制

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