Shaping the Future of Fuel: Monolithic Metal–Organic Frameworks for High-Density Gas Storage

Abstract

The environmental benefits of cleaner, gaseous fuels such as natural gas and hydrogen are widely reported. Yet, practical usage of these fuels is inhibited by current gas storage technology. Here, we discuss the wide-ranging potential of gas-fuels to revolutionize the energy sector and introduce the limitations of current storage technology that prevent this transition from taking place. The practical capabilities of adsorptive gas storage using porous, crystalline metal-organic frameworks (MOFs) are examined with regard to recent benchmark results and ultimate storage targets in this field. In particular, the industrial limitations of typically powdered MOFs are discussed while recent breakthroughs in MOF processing are highlighted. We offer our perspective on the future of practical, rather than purely academic, MOF developments in the increasingly critical field of environmental fuel storage.

Gas Storage in Porous Molecular Materials

“…More recently, Deng and co‐workers were able to oxidize the C 60 cages, to generate partially truncated fullerenes [100] . The open fullerene had a substantially higher uptake, with an outstanding H 2 capacity of 74.12 mmol g −1 reported at 120 bar and 77 K. We note that additional fullerenes have been studied for gas storage (B 40 and B 80 ), [101, 102] but these systems rely on chemisorptive processes that have significant practical barriers [22, 103] …”

“…The often‐low surface areas of typical PCCs likely contributes to the lack of research effort exploring the use of these materials for gas storage applications, where surface areas are generally correlated with gravimetric gas storage capacities. Significant advantages for the processing of molecular materials can be applied to tune and optimize volumetric storage capacities, with these methods typically inaccessible or far more challenging to apply for insoluble, polymeric materials [22] . Recent observations in this area motivate the re‐examination of existing porous cage materials and the development of novel molecular structures for gas storage [170] .…”

Targeted classification of metal–organic frameworks in the Cambridge structural database (CSD)

“…As current on-board containers operate at high pressures (700 bar for Toyota fuel cell vehicles) and room temperature, 71 we predicted the adsorption uptake at 298 K over a range of low to high pressures of 200, 500 and 900 bars. Although highthroughput screening has been widely performed on MOFs for hydrogen storage, very little work published results at these conditions.…”

Gas Adsorption in Amorphous Porous Boron Oxynitride: Grand Canonical Monte Carlo Simulations and Experimental Determination

“…For these purposes, a wide platform of porous materials are currently under research, which include metal-organic frameworks (MOFs), [2][3][4] covalent-organic frameworks (COFs), [5][6][7] activated carbon, [8][9][10] porous organic polymers, [11][12][13] and inorganic compounds such as zeolites. [14][15][16] These materials have been employed across a range of applications, such as gas storage, [17][18][19][20] , drug delivery, [21][22][23][24] water treatment, 25 CO2 capture, [26][27][28][29] and catalysis. [30][31][32][33] Porous boron oxynitride (BNO) has recently emerged as a prominent member of this material platform.…”