A review on on–board challenges of magnesium–based hydrogen storage materials for automobile applications

Abstract

The attempt of the review is to realize on–board hydrogen storage technologies concerning magnesium based solid–state matrix to allow fuel cell devices to facilitate sufficient storage capacity, cost, safety and performance requirements to be competitive with current vehicles. Hydrogen, a potential and clean fuel, can be applied in the state–of–the–art technology of ‘zero emission’ vehicles. Hydrogen economy infrastructure both for stationary and mobile purposes is complicated due to its critical physico–chemical properties and materials play crucial roles in every stage of hydrogen production to utilization in fuel cells in achieving high conversion efficiency, safety and robustness of the technologies involved. Moreover, traditional hydrogen storage facilities are rather complicated due to its anomalous properties such as highly porous solids and polymers have intrinsic microporosity, which is the foremost favorable characteristics of fast kinetics and reversibility, but the major drawback is the low storage capacity. In contrast, metal hydrides and complex hydrides have high hydrogen storage capacity but thermodynamically unfavorable. Therefore, hydrogen storage is a real challenge to realize ‘hydrogen economy’ that will solve the critical issues of humanity such as energy depletion, greenhouse emission, air pollution and ultimately climate change. Magnesium based materials, particularly magnesium hydride (MgH2) has been proposed as a potential hydrogen storage material due to its high gravimetric and volumetric capacity as well as environmentally benign properties to work the grand challenge out.