Molecular Insights into Cage Occupancy of Hydrogen Hydrate: A Computational Study

Authors

Rui Ma, China University of PetroleumFollow
Hong Zhong, China University of PetroleumFollow
Jinxiang Liu, University of JinanFollow
Jie Zhong, University of Nebraska - LincolnFollow
Youguo Yan, China University of PetroleumFollow
Jun Zhang, China University of PetroleumFollow
Jiafang Xu, China University of PetroleumFollow

Date of this Version

2019

Citation

Processes 2019, 7, 699

Comments

© 2019 by the authors.

Open access

doi:10.3390/pr7100699

Abstract

Density functional theory calculations and molecular dynamics simulations were performed to investigate the hydrogen storage capacity in the sII hydrate. Calculation results show that the optimum hydrogen storage capacity is ~5.6 wt%, with the double occupancy in the small cage and quintuple occupancy in the large cage. Molecular dynamics simulations indicate that these multiple occupied hydrogen hydrates can occur at mild conditions, and their stability will be further enhanced by increasing the pressure or decreasing the temperature. Our work highlights that the hydrate is a promising material for storing hydrogen.