Interdisciplinary School of Green Energy/Low-dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology (UNIST), 100 Banyeon, Ulsan 689-798, South Korea.
Proc Natl Acad Sci U S A. 2012 Apr 10;109(15):5588-93. doi: 10.1073/pnas.1116897109. Epub 2012 Mar 27.
Low-cost, high-yield production of graphene nanosheets (GNs) is essential for practical applications. We have achieved high yield of edge-selectively carboxylated graphite (ECG) by a simple ball milling of pristine graphite in the presence of dry ice. The resultant ECG is highly dispersable in various solvents to self-exfoliate into single- and few-layer (≤ 5 layers) GNs. These stable ECG (or GN) dispersions have been used for solution processing, coupled with thermal decarboxylation, to produce large-area GN films for many potential applications ranging from electronic materials to chemical catalysts. The electrical conductivity of a thermally decarboxylated ECG film was found to be as high as 1214 S/cm, which is superior to its GO counterparts. Ball milling can thus provide simple, but efficient and versatile, and eco-friendly (CO(2)-capturing) approaches to low-cost mass production of high-quality GNs for applications where GOs have been exploited and beyond.
低成本、高产率的石墨烯纳米片（GNs）的制备对于实际应用至关重要。我们通过在干冰存在下简单的球磨处理，实现了边缘选择性羧基化石墨（ECG）的高产率。所得的 ECG 在各种溶剂中具有高分散性，可自剥离成单层和少层（≤5 层）的 GNs。这些稳定的 ECG（或 GN）分散体已用于溶液处理，结合热脱羧，可用于生产大面积的 GN 薄膜，用于从电子材料到化学催化剂等许多潜在的应用。热脱羧 ECG 薄膜的电导率高达 1214 S/cm，优于其 GO 对应物。因此，球磨处理为低成本、高质量 GNs 的大规模生产提供了简单、高效、通用且环保（CO2 捕获）的方法，可用于 GO 已经开发和超越的应用领域。
