Mesoporous carbons with self-assembled surfaces of defined crystal orientation
Mesoporous carbons with self-assembled surfaces of defined crystal orientation
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DOI：
10.1016/j.micromeso.2007.04.055
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发表时间：
2008-02-01
影响因子：
5.2
通讯作者：
Hurt, Robert H.
中科院分区：
文献类型：
--
作者：
Jian, Kengqing;Truong, Trung C.;Hurt, Robert H.
碳吸附剂的设计传统上侧重于孔结构以及表面官能团数量和类型的控制。本论文探讨了在紧邻内表面处控制碳晶体结构或石墨烯层取向的潜力。我们假设，这种晶体结构影响碳表面的性质，并影响功能化的活性位点的数量和类型。在这里，一系列的介孔碳制备通过毛细管渗透中间相沥青（萘均聚物）到一系列的控制孔玻璃模板的不同特征孔径，然后碳化和模板蚀刻。已知液晶介晶在液体/二氧化硅界面处采用垂直排列（锚定），这在碳化后导致内表面处的石墨烯边缘位点的高浓度。这些表面被示出具有升高的化学反应性，并且孔结构被示出与基于负副本概念的定量模型的预测一致。总的来说，使用中间相沥青模板介孔碳允许系统和同时控制的孔结构和界面晶体结构，通过液晶表面锚定的明确定义的规则。(c)2007年爱思唯尔公司All rights reserved.
The design of carbon sorbents traditionally focuses on the control of pore structure and the number and type of surface functional groups. The present paper explores the potential of also controlling the carbon crystal structure, or graphene layer orientation, in the immediate vicinity of the internal surfaces. We hypothesize that this crystal structure influences the properties of the carbon surfaces and affects the number and type of active sites for functionalization. Here a series of mesoporous carbons are fabricated by capillary infiltration of mesophase pitch (naphthalene homopolymer) into a series of controlled pore glass templates of different characteristic pore size followed by carbonization and template etching. The liquid crystalline mesogens are known to adopt perpendicular alignment (anchoring) at liquid/silica interfaces, which after carbonization lead to a high concentration of graphene edge sites at the inner surfaces. These surfaces are shown to have elevated chemical reactivity, and the pore structures are shown to be consistent with predictions of a quantitative model based on the negative replica concept. Overall, the use of mesophase pitch for templated mesoporous carbons allows systematic and simultaneous control of both pore structure and interfacial crystal structure through the well-defined rules of liquid crystal surface anchoring. (c) 2007 Elsevier Inc. All rights reserved.