Analyzing the Total Attractive Force and Hydrogen Storage on Two-Dimensional MoP2 at Different Temperatures Using a...

Area of Science:

• Materials Science
• Computational Chemistry
• Energy Storage

Background:

• Hydrogen storage is critical for clean energy technologies.
• Two-dimensional (2D) materials offer unique properties for gas adsorption.
• Molybdenum phosphide (MoP2) is a potential candidate for hydrogen storage applications.

Purpose of the Study:

• To investigate the hydrogen storage capacity of pristine and defective 2D MoP2 using first-principle molecular dynamics (FPMD).
• To determine the influence of molybdenum vacancies on hydrogen adsorption.
• To assess the practical viability of MoP2 for hydrogen storage at different temperatures and pressures.

Main Methods:

• First-principle molecular dynamics (FPMD) calculations were employed to simulate hydrogen adsorption.
• Calculations were performed on both pristine and defective (12.5% Mo vacancies) MoP2 surfaces.
• A two-temperature simulation approach was used to identify stable adsorbed molecules.

Main Results:

• Pristine MoP2 exhibited a gravimetric capacity of 5.72% with an adsorption energy of -0.13 eV/molecule.
• Defective MoP2 showed improved gravimetric capacity of 6.02% with an adsorption energy of -0.14 eV/molecule.
• The defective surface demonstrated a gravimetric capacity ranging from 5.27% at 300 K to 6.02% at 77 K.

Conclusions:

• Defective MoP2 significantly enhances hydrogen storage capacity compared to pristine MoP2.
• The gravimetric capacity of 6.02% at 77 K for defective MoP2 meets US-Department of Energy targets.
• This research highlights the potential of defective 2D MoP2 for practical hydrogen storage solutions.