Impact of Polymers on Magnesium-Based Hydrogen Storage Systems

Abstract

In the present scenario, much importance has been provided to hydrogen energy systems (HES) in the energy sector because of their clean and green behavior during utilization. The developments of novel techniques and materials have focused on overcoming the practical difficulties in the HES (production, storage and utilization). Comparatively, considerable attention needs to be provided in the hydrogen storage systems (HSS) because of physical-based storage (compressed gas, cold/cryo compressed and liquid) issues such as low gravimetric/volumetric density, storage conditions/parameters and safety. In material-based HSS, a high amount of hydrogen can be effectively stored in materials via physical or chemical bonds. In different hydride materials, Mg-based hydrides (Mg–H) showed considerable benefits such as low density, hydrogen uptake and reversibility. However, the inferior sorption kinetics and severe oxidation/contamination at exposure to air limit its benefits. There are numerous kinds of efforts, like the inclusion of catalysts that have been made for Mg–H to alter the thermodynamic-related issues. Still, those efforts do not overcome the oxidation/contamination-related issues. The developments of Mg–H encapsulated by gas-selective polymers can effectively and positively influence hydrogen sorption kinetics and prevent the Mg–H from contaminating (air and moisture). In this review, the impact of different polymers (carboxymethyl cellulose, polystyrene, polyimide, polypyrrole, polyvinylpyrrolidone, polyvinylidene fluoride, polymethylpentene, and poly(methyl methacrylate)) with Mg–H systems has been systematically reviewed. In polymer-encapsulated Mg–H, the polymers act as a barrier for the reaction between Mg–H and O2/H2O, selectively allowing the H2 gas and preventing the aggregation of hydride nanoparticles. Thus, the H2 uptake amount and sorption kinetics improved considerably in Mg–H.

In situ thermal characterisation and filamentary modification in Polymethylpentene

“…Note that PMP can be built in block copolymers, in which polymer blocks are strongly bonded in a covalent method to construct a patterned chemical architecture at the nanoscale [8]. Recently, the material has the potential to make nanomaterial templates [9].…”

Improved Hydrogen Storage Properties and Air Stability of Metal Hydrides by Constructing Heterophase Composites

“…Many works have been carried out to reduce the negative effects of surface oxidation. − On the one hand, the surface oxidation layer can be crushed by the ball milling process, which can create abundant fresh surface and increase the specific surface area at the same time. − This approach, combined with catalytic additives, has been widely used to improve the kinetic properties of magnesium-based hydrogen storage materials. − However, due to the elevated reactivity, the ball-milled hydrides are more sensitive to O 2 and H 2 O in the air and therefore suffer from second surface oxidation . This means that the ball-milled hydrides require a more harsh storage environment to maintain the improved kinetic properties.…”

“…24−26 However, due to the elevated reactivity, the ball-milled hydrides are more sensitive to O 2 and H 2 O in the air and therefore suffer from second surface oxidation. 27 This means that the ball-milled hydrides require a more harsh storage environment to maintain the improved kinetic properties. On the other hand, surface oxidation can be prevented by covering the metal hydrides with a gas-selective layer, which could prevent the permeation of oxygen molecules while allowing the passage of hydrogen molecules.…”

Recent Developments on Bioinspired Cellulose Containing Polymer Nanocomposite Cation and Anion Exchange Membranes for Fuel Cells (PEMFC and AFC)

“…As an example, the chemical energy of hydrogen is 141.865 MJ/kg, whereas gasoline and diesel get chemical energy of 45.58 and 45.4 MJ/kg, respectively [ 13 , 14 ]. “Hydrogen Energy” is majorly classified into three essential sectors, hydrogen production, hydrogen storage, and hydrogen distribution [ 15 , 16 ]. Using numerous techniques, hydrogen can be produced from various sources, such as natural gas, oil, coal, and electrolysis [ 17 , 18 ].…”