||In this study, we used the Density functional theory (DFT) and Molecular dynamics (MD) to obtain the suitable hydrogen storage of platinum nanoclusters on the (5,5) and (9,0) carbon nanotubes (CNTs) and Li atoms on the (5,5) carbon nanotube. platinum nanoclusters on the CNT is chemisorption because hydrogen molecules dissociated. Li atoms on the CNT is physisorption due to hydrogen molecule do not dissociated. We hope that two different hydrogen storage models can achieve the goal which was set by Department of Energy US. There are three parts in this study. There were three parts in this study:|
The first part:
It is very important for obtaining the suitable potential parameters in the Molecular dynamics simulation to reflect the interaction between materials. However, we can not find the suitable parameters from the references to simulate our system. Hence, we use the Force-matching method and Density functional theory to obtain the potential parameter in our system. The Molecular dynamics simulation is utilized to simulate the hydrogen adsorption qith the modified potential parameters.
The second part:
The dynamics behavior of different platinum nanopartilces on the (5, 5) and (9, 0) CNTs at different temperature are investigated by the Molecular dynamics simulation when new parameters are obtained. The migration trajectory, square displacement and mean square displacement of the mass center of platinum nanoclusters are used to analyze to find what sizes of platinum nanoparticle and temperature are the best for hydorgen storage.
The third part:
Density functional theory simulation is utilized to simulate hydrogen molecules adsorbed on the (5, 5) pristine CNT and CNT with lithium atoms. The pressure and temperature effects are used to analyze the hydrogen storage system. Moreover, the different arrangements of CNTs array are also studied, such as, Van der Waals distance (VDW) and shape of array (triangular and square arrangement). Finally, the adsorbed and released phenomenon are also analyzed by the gravimetric capacity (wt%) of hydrogen molecule for hydrogen.