Nanostructured Metal Hydrides for Hydrogen Storage

Abstract

Knowledge and foundational understanding of phenomena associated with the behavior of materials at the nanoscale is one of the key scientific challenges toward a sustainable energy future. Size reduction from bulk to the nanoscale leads to a variety of exciting and anomalous phenomena due to enhanced surface-to-volume ratio, reduced transport length, and tunable nanointerfaces. Nanostructured metal hydrides are an important class of materials with significant potential for energy storage applications. Hydrogen storage in nanoscale metal hydrides has been recognized as a potentially transformative technology, and the field is now growing steadily due to the ability to tune the material properties more independently and drastically compared to those of their bulk counterparts. The numerous advantages of nanostructured metal hydrides compared to bulk include improved reversibility, altered heats of hydrogen absorption/desorption, nanointerfacial reaction pathways with faster rates, and new surface states capable of activating chemical bonds. This review aims to summarize the progress to date in the area of nanostructured metal hydrides and intends to understand and explain the underpinnings of the innovative concepts and strategies developed over the past decade to tune the thermodynamics and kinetics of hydrogen storage reactions. These recent achievements have the potential to propel further the prospects of tuning the hydride properties at nanoscale, with several promising directions and strategies that could lead to the next generation of solid-state materials for hydrogen storage applications.

Recent developments in the fabrication, characterization and implementation of MgH2-based solid-hydrogen materials in the Kuwait Institute for Scientific Research

“…Although AlH 3 has a good storage capacity (10 wt%) and a relatively low decomposition temperature (60-140 C), AlH 3 is not reversible. Schneemann et al 108 have recently published an important review article, discussing the potential applications of different nanostructured metal hydrides and their hydrogen storage properties. 108 MgH 2 , with its high storage capacity (7.6 wt%), great cyclability, natural abundance, and low cost has been considered as the most suitable hydrogen storage material for fuel cell applications.…”

“…Schneemann et al 108 have recently published an important review article, discussing the potential applications of different nanostructured metal hydrides and their hydrogen storage properties. 108 MgH 2 , with its high storage capacity (7.6 wt%), great cyclability, natural abundance, and low cost has been considered as the most suitable hydrogen storage material for fuel cell applications. Unfortunately, MgH 2 has several drawbacks related to its high thermal stability, slow kinetics of hydrogenation and dehydrogenation and high apparent activation energy.…”

“…many review articles have presented and discussed the possibility of designing Mg-based nanomaterials for hydrogen storage. [107][108][109] In 2017, a comprehensive review article published by Zhang et al presented the recent progress achieved to improve MgH 2 through catalytic agents and nanoconnement. 110 Mg and Mg 2 Ni were suggested 52 years ago as being suitable for use in internal combustion engines in the car industry.…”

Magnesium Nanoparticles With Pd Decoration for Hydrogen Storage

“…In order to overcome these drawbacks of MgH 2 for practical applications, numerous studies attempted to enhance the hydrogen storage performance of MgH 2 , such by as alloying Mg with other elements to alter the thermodynamic stability, doping with additives or catalysts, and reducing Mg particles to nano scale. "Nanosize effect" has been considered as an approach with the potential of leading to improvements in both kinetics and thermodynamics (Schneemann et al, 2018), which is based on (i) a larger surface area and thus more hydrogen dissociation sites (ii) the shortened hydrogen diffusion distances which in turn enhance kinetics, and (iii) the increased number of atoms at grain boundaries to enhance the hydrogen diffusion rates (Yao et al, 2011;Schneemann et al, 2018;Sun et al, 2018). Recently, an adapted Rieke method has emerged as an alternative to synthesize Mg nanoparticles to dramatically enhance the hydrogen sorption kinetics of Mg. For instance, Jeon et al (2011) reported the synthesis of air-stable Mg nanoparticles (∼4.9 nm) embedded in PMMA matrix, which enable both the storage of a high hydrogen capacity and rapid kinetics.…”

CaXH 3 (X = Mn, Fe, Co) perovskite‐type hydrides for hydrogen storage applications

“…7,12 In this area, metal and complex metal hydrides, intermetallic hydrides, complex chemical hydrides, nanostructured carbon materials, and metalorganic compounds have become research materials to develop the technology in interest. [16][17][18][19] Among them, the perovskite-type hydrides have been promising candidate for solid-state type of future hydrogen storage materials. [20][21][22][23][24][25][26][27][28] There are numerous number of perovskite compounds that can be obtained as carbides, nitrides, fluorides, chlorides, bromides, oxides, hydrides, and iodides.…”