Amorphous TiCu-Based Additives for Improving Hydrogen Storage Properties of Magnesium Hydride

Area of Science:

• Materials Science
• Energy Storage
• Nanotechnology

Background:

• Magnesium hydride (MgH2) is a promising material for hydrogen and heat storage due to its high capacity and low cost.
• Improving MgH2's hydrogen storage properties often involves catalytic doping.
• Amorphous TiCu-based alloys are explored as catalysts for MgH2.

Purpose of the Study:

• To investigate the catalytic effects of amorphous and crystalline TiCu-based alloys on MgH2 for hydrogen storage.
• To evaluate the performance and stability of MgH2 doped with amorphous Ti45Cu41Ni9Zr5 alloy.

Main Methods:

• High-energy mechanochemical synthesis was used to prepare nanostructured MgH2 doped with amorphous or crystalline TiCu-based alloys.
• Transmission electron microscopy (TEM) was employed for microstructural analysis.
• Pressure-composition-temperature (PCT) analysis was conducted to determine thermodynamic properties.

Main Results:

• Amorphous TiCu additives demonstrated superior catalytic effects compared to crystalline alloys.
• MgH2 doped with amorphous Ti45Cu41Ni9Zr5 exhibited improved dehydrogenation kinetics and stability during cycling at 300 °C.
• The amorphous TiCu-based catalysts remained thermally stable up to 360 °C, with a calculated reaction enthalpy of -78.7 kJ/mol·H2 and entropy of 145.0 J/K·mol·H2.

Conclusions:

• Amorphous TiCu-based alloys are effective catalysts for enhancing the hydrogen storage properties of MgH2.
• The nanostructured MgH2 system catalyzed by amorphous TiCu shows good cycling stability and thermal stability.
• This study highlights the potential of amorphous TiCu alloys for developing advanced MgH2-based hydrogen storage materials.