Kondratyuk Petro, Wang Yang, Johnson J Karl, Yates John T
Surface Science Center, Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA.
J Phys Chem B. 2005 Nov 10;109(44):20999-1005. doi: 10.1021/jp0582078.
Three well-defined adsorption sites have been found on opened single-wall carbon nanotubes by temperature-programmed desorption measurements for several alkanes. A series of linear chain alkanes from pentane to nonane, as well as a branched alkane molecule, 2,2,4-trimethylpentane, were used to elucidate the effect of molecular length on the capacity of the adsorption sites. The two highest-energy adsorption sites were assigned as the nanotube interior sites and groove sites on the outside of the nanotube bundles. Hybrid Monte Carlo simulations were performed to probe the molecular-level details of adsorption. Both in experiments and in the simulation, the groove sites were seen to behave as one-dimensional adsorption space, demonstrating an inverse dependence of capacity on the length of the adsorbed molecule. In contrast, the capacity of the internal sites was found to depend inversely on the volume occupied by the molecule.
通过对几种烷烃进行程序升温脱附测量，在开口单壁碳纳米管上发现了三个明确的吸附位点。使用一系列从戊烷到壬烷的直链烷烃以及一个支链烷烃分子2,2,4-三甲基戊烷来阐明分子长度对吸附位点容量的影响。两个能量最高的吸附位点被确定为纳米管内部位点和纳米管束外部的沟槽位点。进行了混合蒙特卡罗模拟以探究吸附的分子水平细节。在实验和模拟中，都观察到沟槽位点表现为一维吸附空间，表明容量与吸附分子长度呈反比关系。相比之下，发现内部位点的容量与分子占据的体积成反比。
