Hydrogen Storage with Aluminum Formate, ALF: Experimental, Computational, and Technoeconomic Studies

Abstract

Long-duration storage of hydrogen is necessary for coupling renewable H 2 with stationary fuel cell power applications. In this work, aluminum formate (ALF), which adopts the ReO 3type structure, is shown to have remarkable H 2 storage performance at non-cryogenic (>120 K) temperatures and low pressures. The most promising performance of ALF is found between 120 K and 160 K and at 10 bar to 20 bar. The study illustrates H 2 adsorption performance of ALF over the 77 K to 296 K temperature range using gas isotherms, in situ neutron powder diffraction, and DFT calculations, as well as technoeconomic analysis (TEA), illustrating ALF's competitive performance for long-duration storage versus compressed hydrogen and leading metal−organic frameworks. In the TEA, it is shown that ALF's storage capacity, when combined with a temperature/pressure swing process, has advantages versus compressed H 2 at a fraction of the pressure (15 bar versus 350 bar). Given ALF's performance in the 10 bar to 20 bar regime under moderate cooling, it is particularly promising for use in safe storage systems serving fuel cells.

Effect of Hf Dopant on Resistance to CO Toxicity on ZrCo(110) Surface for H Adsorption

“…Safe and efficient hydrogen storage is one of the biggest and most challenging obstacles to the more widespread usage of hydrogen [3][4][5]. Among different hydrogen storage systems [6][7][8][9], alloys are important and widely used as hydrogen storage materials. From the perspective of practical application, the hydrogen storage alloys should be stable and must be able to resist the toxic effect of impurity gases [10,11], such as carbon monoxide (CO), that are produced in the process of steam hydrogen production.…”

Long Duration Energy Storage Using Hydrogen in Metal–Organic Frameworks: Opportunities and Challenges

“…Despite having higher LCOS under the same MOF price range, Type 3 MOFs have higher chances of achieving the cheapest material cost using abundant metals and linkers. Further, their capability of achieving moderate uptake under low pressure (∼10 g/kg at ∼10 bar) could make them an ideal candidate for high-pressure electrolyzers (>30 bar, while this Perspective assumes 2 bar). , …”

“…Recently, a third type of MOF has emerged in the H 2 storage literature, which is designed to be synthesized via abundant and cheap materials (i.e., aluminum and formic acid), while retaining H 2 uptake. Type 3 MOF requires more cooling than Type 2 but reaches its peak performance under low-pressure conditions . Evans et al report a low optimum pressure range (10–40 bar), which remains high enough to transfer H 2 into fuel cells .…”

“…Further, their capability of achieving moderate uptake under low pressure (∼10 g/kg at ∼10 bar) could make them an ideal candidate for high-pressure electrolyzers (>30 bar, while this Perspective assumes 2 bar). 33,38 Besides pressure, heat and cooling management is affected by the way in which storage systems are integrated into H 2 production and end use. When coupled with electrolyzers, MOF-based H 2 storage requires that the H 2 be compressed and cooled at the same time, which increases energy consumption.…”

“…Type 3 MOF requires more cooling than Type 2 but reaches its peak performance under low-pressure conditions. 33 Evans et al report a low optimum pressure range (10–40 bar), which remains high enough to transfer H 2 into fuel cells. 33 The generalization for Type 2 and Type 3 MOFs needs further evaluation, which requires more experimental data, particularly for Type 3, related to isotherm assumptions under broad temperature ranges (see SI Section S2 for discussion).…”