Deerattrakul Varisara, Hirunpinyopas Wisit, Pisitpipathsin Nuttapon, Saisopa Thanit, Sawangphruk Montree, Nualchimplee Chakrit, Iamprasertkun Pawin
Department of Applied physics, Faculty of Sciences and Liberal Arts, Rajamangala University of Technology Isan, Nakhon Ratchasima 30000, Thailand.
Department of Chemistry, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand.
Phys Chem Chem Phys. 2021 May 26;23(20):11616-11623. doi: 10.1039/d1cp00887k.
Recently, graphene-based materials have become ubiquitous in electrochemical devices including electrochemical sensors, electrocatalysts, capacitive and membrane desalination and energy storage devices. However, many of the electrochemical properties of graphene (particularly the capacitance and ionic transport) are not yet fully understood. This paper explores the capacitance and ionic transport properties of size dependent graphene (from 100 nm to 1 μm) prepared through the liquid phase exfoliation of graphite in which the size of graphene was finely selected using a multi-step centrifugation technique. Our experiment was then expanded to include basal plane graphene using highly ordered pyrolytic graphite as a model electrode, describing the assumed theoretical graphene capacitance (quoted as 550 F g-1 or 21 μF cm-2) and the electrochemical surface area of the carbon-based materials. This work improves our understanding of graphene electrochemistry (capacitance and ion transport), which should lead to the continuing development of many high-performance electrochemical devices, especially supercapacitors, capacitive desalination and ion-based selective membranes.
近年来，基于石墨烯的材料在包括电化学传感器、电催化剂、电容式和膜脱盐以及能量存储装置在内的电化学器件中已变得无处不在。然而，石墨烯的许多电化学性质（特别是电容和离子传输）尚未得到充分理解。本文探究了通过石墨的液相剥离制备的尺寸依赖性石墨烯（尺寸范围从100纳米至1微米）的电容和离子传输性质，其中使用多步离心技术精细选择了石墨烯的尺寸。然后，我们的实验扩展到使用高度有序热解石墨作为模型电极的基面石墨烯，描述了假定的理论石墨烯电容（记为550 F g-1或21 μF cm-2）以及碳基材料的电化学表面积。这项工作增进了我们对石墨烯电化学（电容和离子传输）的理解，这将推动许多高性能电化学器件的持续发展，尤其是超级电容器、电容式脱盐和基于离子的选择性膜。
