碳纳米管阵列储氢的分子动力学模拟

采用分子动力学方法,模拟了常温和不同压强下,氢在不同管径和管间距的单壁碳纳米管阵列(SWCNTA—S ingle-walled Carbon Nanotube Arrays)中的物理吸附过程.重点研究了压强、管径和管间距对SWCNTA(管内和管间隙)物理吸附储氢的影响.发现氢分子主要储存在SWCNTA的管壁附近,适当地增大管径和管间距可有效增加SWCNTA的物理吸附储氢量,使其在常温下具有较高的储氢能力,并给出了相应的理论解释.计算结果表明,在常温和中等压强下,SWCNTA的物理吸附总储氢量(重量百分比)可达4.2%,从而为同等条件下SWCNTA具有较高储氢能力的实验结果提供了直接的理论支持.

Molecular dynamics simulation of hydrogen physisorption in single-walled carbon nanotube arrays

Processes of hydrogen physisorption in single-walled carbon nanotube arrays(SWCNTA) with different tube diameters and inter-tube distances are simulated by the molecular dynamics method on the condition of different pressure at normal temperature.The influences of pressure,tube diameter and inter-tube distance on hydrogen physisorption in SWCNTA,inside of the tubes and in the tube interstices,have been investigated in detail.We find that hydrogen molecules are mostly absorbed near the tube walls of SWCNTA,and increasing the tube diameter and inter-tube distance properly can improve the hydrogen storage capacity of SWCNTA effectively,which makes SWCNTA have higher capability for hydrogen storage at normal temperature.And their theoretic explanations are also given.Our computational results show that the total gravimetric hydrogen storage capacity of SWCNTA can reach 4.2% at normal temperature and moderate pressure,and offer a theoretical support for the experimental results,which reported in Ref.\ that the gravimetric hydrogen storage capacity of SWCNTA at normal temperature and moderate pressure is 4.2%.