Nanostructuring of Mg-Based Hydrogen Storage Materials: Recent Advances for Promoting Key Applications

• Published in: Nano-micro letters Vol. 15; no. 1; p. 93
• Main Authors: Ren, Li, Li, Yinghui, Zhang, Ning, Li, Zi, Lin, Xi, Zhu, Wen, Lu, Chong, Ding, Wenjiang, Zou, Jianxin
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01-12-2023; Springer Nature B.V; SpringerOpen
• Subjects: Chemical reduction; Clean energy; Composite materials; Desorption; Energy Conversion and Storage; Energy sources; Engineering; Fossil fuels; Heterostructures; Hydrogen; Hydrogen storage; Hydrogen storage materials; Kinetics; Low cost; Mechanical milling; Mg-based hydrogen storage materials; Nanoscale Science and Technology; Nanostructure; Nanotechnology; Nanotechnology and Microengineering; On-board hydrogen storage; R&D; Research & development; Review; Room temperature; Sorption; Storage capacity; Thermal management; Thermodynamics; Ultrasonic methods; Thermodynamics; Hydrogen storage; Nanostructure; Kinetics; Mg-based hydrogen storage materials; On-board hydrogen storage
• ISSN: 2311-6706; 2150-5551
• DOI: 10.1007/s40820-023-01041-5

Highlights
A comprehensive discussion of the recent advances in the nanostructure engineering of Mg-based hydrogen storage materials is presented.
The fundamental theories of hydrogen storage in nanostructured Mg-based hydrogen storage materials and their practical applications are reviewed.
The challenges and recommendations of current nanostructured hydrogen storage materials are pointed out.
With the depletion of fossil fuels and global warming, there is an urgent demand to seek green, low-cost, and high-efficiency energy resources. Hydrogen has been considered as a potential candidate to replace fossil fuels, due to its high gravimetric energy density (142 MJ kg
−1
), high abundance (H
2
O), and environmental-friendliness. However, due to its low volume density, effective and safe hydrogen storage techniques are now becoming the bottleneck for the "hydrogen economy". Under such a circumstance, Mg-based hydrogen storage materials garnered tremendous interests due to their high hydrogen storage capacity (~ 7.6 wt% for MgH
2
), low cost, and excellent reversibility. However, the high thermodynamic stability (ΔH =  − 74.7 kJ mol
−1
H
2
) and sluggish kinetics result in a relatively high desorption temperature (> 300 °C), which severely restricts widespread applications of MgH
2
. Nano-structuring has been proven to be an effective strategy that can simultaneously enhance the ab/de-sorption thermodynamic and kinetic properties of MgH
2
, possibly meeting the demand for rapid hydrogen desorption, economic viability, and effective thermal management in practical applications. Herein, the fundamental theories, recent advances, and practical applications of the nanostructured Mg-based hydrogen storage materials are discussed. The synthetic strategies are classified into four categories: free-standing nano-sized Mg/MgH
2
through electrochemical/vapor-transport/ultrasonic methods, nanostructured Mg-based composites via mechanical milling methods, construction of core-shell nano-structured Mg-based composites by chemical reduction approaches, and multi-dimensional nano-sized Mg-based heterostructure by nanoconfinement strategy. Through applying these strategies, near room temperature ab/de-sorption (< 100 °C) with considerable high capacity (> 6 wt%) has been achieved in nano Mg/MgH
2
systems. Some perspectives on the future research and development of nanostructured hydrogen storage materials are also provided.
Graphical Abstract