Molecular Dynamics Study Of Hydrogen Storage In Carbon Nanotube Arrays

The significance of studying hydrogen storage in carbon nanotubes (CNTs) is illuminated firstly in this article, and the CNTs as a promising new material for hydrogen storage are interpreted.Secondly, the development in experimental and theoretical researches of hydrogen storage in CNTs since 1997 was reviewed. Main experimental and theoretic results are compared and the discrepancy between them is generalized. We introduce three main methods of theoretical study on hydrogen storage in CNTs: 1. Grand Canonical Monte Carlo (GCMC) method based on all kinds of potential functions. 2. Classical Molecular Dynamics (MD) method based on all kinds of potential functions. 3. Density Function Theory (DFT) based on quantum theory.Thirdly, the work by author is introduced in detail. The main contents include ? the foundation of MD simulation cell in Grand Canonical Ensemble (GCE); ? the establishment of elastic collision mechanism between hydrogen molecules and carbon nanotube walls and arithmetic design; ? molecular dynamics simulation details of hydrogen physisorption in single walled carbon nanotube arrays (SWCNTA) and program design; ? the acquirement and analysis of computer simulation results, where the influences of tube diameter, distance between tubes, temperature and pressure on hydrogen physisorption in SWCNTA are investigated in detail. In this paper, (1) and (2) are innovative work.By induction and analyzing a large number of data obtained from the simulations, we point out that increasing pressure and decreasing temperature properly, and choosing the diameters and distances between tubes of SWCNTA reasonably, can improve the hydrogen storage capacity of SWCNTA effectively. And then their theoretic explanations are also discussed. Furthermore, comparing our results with the results obtained from GCMC simulation indicates that the MD method presented in this paper for GCE simulation is correct and feasible.At last, the conclusions of this paper and the suggestions of further study are given.