共查询到20条相似文献,搜索用时 46 毫秒
1.
《International Journal of Hydrogen Energy》2022,47(67):28932-28944
Cryo-compressed hydrogen (CcH2) is a promising hydrogen storage method with merits of high density with low power consumption. Thermodynamic analysis and comparison of several CcH2 processes are conducted in this paper, under hydrogen storage conditions of 10–100 MPa at 60–100 K. Mixed-refrigerant J-T (MRJT), nitrogen/neon reverse Brayton (RBC) and hydrogen expansion are employed for cooling hydrogen, respectively. Combined CcH2 processes such as MRJT + neon-RBC are proposed to reach higher CcH2 density at lower temperatures (<80 K). It was indicated that the specific power consumptions (SPC) of MRJT processes are obviously lower than those of nitrogen/neon-RBC or hydrogen expansion processes. For a typical storage condition of 50 MPa at 80 K, MRJT CcH2 process could achieve hydrogen density of 71.59 kg m?3, above liquid hydrogen. While its SPC of 6.42 kWh kg?1 is about 40% lower than current dual-pressure Claude hydrogen liquefaction processes (10.85 kWh kg?1). 相似文献
2.
《International Journal of Hydrogen Energy》2019,44(31):16833-16840
Safe, reliable, and economic hydrogen storage is a bottleneck for large-scale hydrogen utilization. In this paper, hydrogen storage methods based on the ambient temperature compressed gaseous hydrogen (CGH2), liquid hydrogen (LH2) and cryo-compressed hydrogen (CcH2) are analyzed. There exists the optimal states, defined by temperature and pressure, for hydrogen storage in CcH2 method. The ratio of the hydrogen density obtained to the electrical energy consumed exhibits a maximum value at the pressures above 15 MPa. The electrical energy consumed consists of compression and cooling down processes from 0.1 MPa at 300 K to the optimal states. The recommended parameters for hydrogen storage are at 35–110 K and 5–70 MPa regardless of ortho-to parahydrogen conversion. The corresponding hydrogen density at the optimal states range from 60.0 to 71.5 kg m−3 and the ratio of the hydrogen density obtained to the electrical energy consumed ranges from 1.50 to 2.30 kg m−3 kW−1. While the ortho-to para-hydrogen conversion is considered, the optimal states move to a slightly higher temperatures comparing to calculations without ortho-to para-hydrogen conversion. 相似文献
3.
Song Hu Yongliang Yong Zijia Zhao Ruilin Gao Qingxiao Zhou Yanmin Kuang 《International Journal of Hydrogen Energy》2021,46(42):21994-22003
Searching advanced materials with high capacity and efficient reversibility for hydrogen storage is a key issue for the development of hydrogen energy. In this work, we studied systematically the hydrogen storage properties of the pure C7N6 monolayer using density functional theory methods. Our results demonstrate that H2 molecules are spontaneously adsorbed on the C7N6 monolayer with the average adsorption energy in the range of 0.187–0.202 eV. The interactions between H2 molecules and C7N6 monolayer are of electrostatic nature. The gravimetric and volumetric hydrogen storage capacities of the C7N6 monolayer are found to be 11.1 wt% and 169 g/L, respectively. High hardness and low electrophilicity provides the stabilities of H2–C7N6 systems. The hydrogenation/dehydrogenation (desorption) temperature is predicted to be 239 K. The desorption temperatures and desorption capacity of H2 under practical conditions further reveal that the C7N6 monolayer could operate as reversible hydrogen storage media. Our results thus indicate that the C7N6 monolayer is a promising material with efficient, reversible, and high capacity for H2 storage under realistic conditions. 相似文献
4.
R.K. Ahluwalia J.K. Peng H.S. Roh T.Q. Hua C. Houchins B.D. James 《International Journal of Hydrogen Energy》2018,43(22):10215-10231
Liquid hydrogen (LH2) truck delivery and storage at dispensing sites is likely to play an important role in an emerging H2 infrastructure. We analyzed the performance of single phase, supercritical, on-board cryo-compressed hydrogen storage (CcH2) with commercially-available LH2 pump enabled single-flow refueling for application to fuel cell electric buses (FCEB). We conducted finite-element stress analyses of Type 3 CcH2 tanks using ABAQUS for carbon fiber requirement and Fe-Safe for fatigue life. The results from these analyses indicate that, from the standpoint of weight, volume and cost, 2-mm 316 stainless steel liner is preferred to aluminium 6061 alloy in meeting the required 15,000 charge-discharge cycles for 350–700 bar storage pressures. Compared to the Type 3, 350 bar, ambient-temperature H2 storage systems in current demonstration FCEBs, 500-bar CcH2 storage system is projected to achieve 91% improvement in gravimetric capacity, 175% improvement in volumetric capacity, 46% reduction in carbon fiber composite mass, and 21% lower system cost, while exceeding >7 day loss-free dormancy with initially 85%-full H2 tank. 相似文献
5.
Jin-Ho Kim Yong-Mook Kang Min-Sik ParkKwang-Taek Hwang 《International Journal of Hydrogen Energy》2011,36(16):9714-9718
Li-Mg-N-H systems have been focused on as one of the most promising hydrogen storage systems owing to their high hydrogen contents and binary nitride, LiMgN, has a high gravimetric storage density of 8.2 wt% H2. We synthesized LiMgN by a hydriding thermal reaction between Mg and LiNH2 under various H2 pressures and a subsequent dehydrogenation reaction, and optimized conditions for the formation of pure LiMgN. The results demonstrate that pure LiMgN can be produced using hydriding thermal synthesis at 80 bar H2 pressure and 723 K. The hydriding and dehydriding characteristics of as-synthesized LiMgN were investigated by a Sievers’ type instrument. The reaction product LiMgN can be rehydrogenated by reacting with H2 under 80 bar of hydrogen pressure at 573 K, and then released under less than 0.5 bar at 573 K. The measured H2 capacity is about 6.8 wt% during the hydrogenation process. 相似文献
6.
《International Journal of Hydrogen Energy》2022,47(44):19146-19154
The hydrogen adsorption and storage of the lithium-decorated PdS2 monolayer at nano-size has been investigated by using extended tight-binding (GFN1-xTB) based on density functional theory (DFT). The calculation results demonstrate that the average adsorption energies of 1–5H2 change in 0.47–0.20 eV/H2 range which decreases with increasing of adsorbed hydrogen molecule number. The gravimetric density for hydrogen storage adsorption with 12Li atom and 60H2 molecules of Li-decorated PdS2 monolayer is about 6.98 wt% considered as possible application in hydrogen storage. The examination of the hydrogen store mechanism between the monolayer and hydrogen molecules is presented by polarization between Pd and H2, which can be effect on the adsorption behavior. 相似文献
7.
The effect of light metal ion decoration of the organic linker in metal-organic framework MOF-5 on its hydrogen adsorption with respect to its hydrogen binding energy (ΔB.E.) and gravimetric storage capacity is examined theoretically by employing models of the form MC6H6:nH2 where M = Li+, Na+, Be2+, Mg2+, and Al3+. A systematic investigation of the suitability of DFT functionals for studying such systems is also carried out. Our results show that the interaction energy (ΔE) of the metal ion M with the benzene ring, ΔB.E., and charge transfer (Qtrans) from the metal to benzene ring exhibit the same increasing order: Na+ < Li+ < Mg2+ < Be2+ < Al3+. Organic linker decoration with the above metal ions strengthened H2-MOF-5 interactions relative to its pure state. However, amongst these ions only Mg2+ ion resulted in ΔB.E. magnitudes that were optimal for allowing room temperature hydrogen storage applications of MOF-5. A much higher gravimetric storage capacity (6.15 wt.% H2) is also predicted for Mg2+-decorated MOF-5 as compared to both pure MOF-5 and Li+-decorated MOF-5. 相似文献
8.
Deepak Kag Nitin Luhadiya Nagesh D. Patil S.I. Kundalwal 《International Journal of Hydrogen Energy》2021,46(43):22599-22610
The adsorption of hydrogen molecules on monolayer graphene is investigated using molecular dynamics simulations (MDS). Interatomic interactions of the graphene layer are described using the well-known AIREBO potential, while the interactions between graphene and hydrogen molecule are described using Lennard-Jones potential. In particular, the effect of strain and different point defects on the hydrogen storage capability of graphene is studied. The strained graphene layer is found to be more active for hydrogen and show 6.28 wt% of H2 storage at 0.1 strain at 77 K temperature and 10 bar pressure. We also studied the effect of temperature and pressure on the adsorption energy and gravimetric density of H2 on graphene. We considered different point defects in the graphene layer like monovacancy (MV), Stone Wales (SW), 5-8-5 double vacancy (DV), 555–777 DV, and 5555-6-7777 DV which usually occur during the synthesis of graphene. At 100 bar pressure, graphene with 1% concentration of MV defects leads to 9.3 wt% and 2.208 wt% of H2 storage at 77 K and 300 K, respectively, which is about 42% higher than the adsorption capacity of pristine graphene. Impact of defects on the critical stress and strain of defected graphene layers is also studied. 相似文献
9.
《International Journal of Hydrogen Energy》2023,48(66):25821-25829
Based on the density functional theory, we investigate the electronic properties of the clusters M2B7 (M = Be, Mg, Ca) and their hydrogen storage properties systematically in this paper. Extensive global search results show that the global minimal structures of the three systems (Be2B7, Mg2B7 and Ca2B7) are heptagonal biconical structure, and the two alkaline earth metals are located at the top of the biconical. Chemical bonding analyses show that M2B7 clusters have 6σ and 6π delocalized electrons, which are doubly aromatic. At the wB97XD level, the three systems have good hydrogen storage capabilities. The hydrogen storage density of Be2B7 is as high as 23.03 wt%, while Mg2B7 and Ca2B7 also far exceed the hydrogen storage target set by the U.S. Department of Energy in 2017. Their average adsorption energies of H2 molecules all ranged from 0.1 eV/H2 to 0.48 eV/H2, which is fall in between physisorption and chemisorption. Extensive Born Oppenheimer molecular dynamics (BOMD) simulations show that the H2 molecules of the three systems can be completely released at a certain temperature. Therefore, M2B7 systems can achieve reversible adsorption of H2 molecules at normal temperature and pressure. It can be seen that the B7 clusters modified by alkaline earth metals may become a promising new nano-hydrogen storage material. 相似文献
10.
《International Journal of Hydrogen Energy》2022,47(93):39586-39594
The H2 storage properties of isoreticular metal-organic framework materials (IRMOFs), MOF-5 and IRMOF-10, impregnated with different numbers and types of heterogeneous C48B12 molecules were investigated using density functional theory and grand canonical Monte Carlo (GCMC) calculations. The excess hydrogen adsorption isotherms of IRMOFs at 77 K within 20 bar indicate that suitable number and type of C48B12 molecules play a crucial role in improving the H2 storage properties of IRMOFs. Among the studied pure and nC48B12 (n = 1, 2, 4, 8) in Ci symmetry impregnating into MOF-5, at 77 K under 6 bar, MOF-5-4C48B12 with a 3.5 wt% and 29.9 g/L hydrogen storage density, and at 77 K under 12 bar, the pure MOF-5 with a 4.9 wt% and 31.0 g/L hydrogen storage density has the best hydrogen storage properties. Whereas, among the studied pure and nC48B12 (n = 1, 2, 4, 8) in S6 symmetry impregnating into IRMOF-10, IRMOF-10-8C48B12 always shows the best hydrogen storage properties among the pure and C48B12-impregnated IRMOF-10 at 77 K within 20 bar. IRMOF-10-8C48B12 has a 6.0 wt% and 34.6 g/L hydrogen storage density at 77 K under 6 bar, and has a 7.1 wt% and 41.4 g/L hydrogen storage density at 77 K under 12 bar. The confinement effect of IRMOFs on C48B12 molecules, and steric hindrance effect of C48B12 molecules on IRMOFs mainly affects the H2 uptake capacity by comparing the absolute H2 molecules in individual IRMOFs units, C48B12 molecules, and IRMOFs-nC48B12 compounds. The absolute hydrogen adsorption profiles show that eight C48B12 molecules impregnating into MOF-5 can exert obvious steric effects for H2 adsorption. The saturated gravimetric and volumetric H2 densities of IRMOF-10-8C48B12 higher than those of MOF-5-8C48B12 due to with larger free volume. 相似文献
11.
《International Journal of Hydrogen Energy》2020,45(60):34972-34982
Hydrogen storage capacity on Cu(I)-exchanged SSZ-39 (AEI), -SSZ-13 (CHA) and Ultra stable-Y (US–Y, FAU) at temperatures between 279 K and 304 K are investigated. The gravimetric hydrogen storage capacity values reaching 83 μmol H2 g−1 (at 279 K and 1 bar) are found to be comparable with the highest adsorption capacity values reported on metal-organic frameworks. The volumetric hydrogen storage capacity values; on the other hand, are found to be more than three times of those reported on metal-organic frameworks (0.57 g/L on Cu(I)-SSZ-39 at 1 bar and 296 K vs. ca. 0.18 g/L on Co2(m-dobdc) at 1 bar and 298 K (Kapelewski MT, Runčevski T, Tarver JD, Jiang HZH, Hurst KE, Parilla PA et al. Record High Hydrogen Storage Capacity in the Metal-Organic Framework Ni2(m-dobdc) at Near-Ambient Temperatures. Chem Mater 2018; 30:8179–89)). The isosteric heat of adsorption values are calculated to be between 80 kJ mol−1 and 49 kJ mol−1 on Cu(I)-SSZ-39 and between 22 kJ mol−1 and 15 kJ mol−1 on Cu(I)-US-Y indicating H2 adsorption mainly at Cu(I) cations located at the eight-membered rings on Cu(I)-SSZ-39 and at six-membered rings on Cu(I)-US-Y. Hydrogen adsorption experiments performed at 77 K showed higher adsorption capacity values for Cu(I)-SSZ-39 at 1 bar, but Cu(I)-US-Y showed potential for hydrogen storage at higher pressure values. 相似文献
12.
《International Journal of Hydrogen Energy》2020,45(55):30818-30827
In this paper, we report here the hydrogen storage capacity of activated carbon aerogel synthesized by ambient pressure drying using a new catalyst. The carbon aerogel (CA) has been synthesized by the sol-gel method using resorcinol (R) and formaldehyde (F). For drying of RF wet gel instead of expensive and unsafe supercritical process, we have used ambient pressure drying. To avoid shrinkage which may occur due to this mode of drying, instead of usual catalyst (C): Na2CO3, organic catalyst triethylamine (TEA), which is known to be a condensing agent has been used. In order to find out the effect of change of R/C ratio on hydrogen sorption, three different R/C namely CA 1000, CA 2000, and CA 3000 were taken. Structural and microstructural details have been studied employing XRD, SEM, TEM, nitrogen adsorption, FTIR, and Raman spectroscopy. TEM and nitrogen adsorption studies have revealed that aerogel with R/C 1000 exhibits a higher degree of micropore density. The hydrogen storage capacities for all R/C ratios have been determined. It has been found that carbon aerogel (CA) with R/C = 1000, exhibits the highest hydrogen adsorption capacity out of the three aerogels. At liquid nitrogen temperature, the hydrogen storage capacity of aerogel with R/C = 1000 for the as-synthesized and activated carbons have been found to be 4.00 wt % and 4.80 wt %. A viable reason for the occurrence of high hydrogen storage capacity at liquid nitrogen temperature for aerogel with R/C = 1000 has been put forward. 相似文献
13.
“Similar self-preservation” and decomposition kinetics of tetrahydrofuran-hydrogen hydrate particles
《International Journal of Hydrogen Energy》2022,47(13):8457-8466
Storage hydrogen using hydrates is a promising alternative to other hydrogen storage technologies. In this work, the effects of pressure and temperature on the decomposition kinetics of binary THF-H2 hydrates was investigated systematically in the pressure range of 0.1 MPa–7 MPa and temperature from 243 K to 273 K. The results showed that the dissociation of THF-H2 hydrates could be divided into three stages, rapid decomposition, slow decomposition, and stable state. The higher the pressure, the lower the dissociation rate of THF-H2 hydrates in the final stable stage. It was worth to note that the dissociation rate of THF-H2 hydrates does not show a simple linear relationship with temperature. The anomalous phenomenon of THF-H2 hydrates dissociation was observed in the temperature region of 253 K and 268 K under 5 MPa, especially at 268 K, and it was called “similar self-preservation” phenomenon. The dissociation ratio of THF-H2 hydrates in 80 h was not more than 50 mol% at 268 K and 5 MPa. This study provides practical way for developing clathrate hydrate-based storage hydrogen (transport and application) in the future. 相似文献
14.
《International Journal of Hydrogen Energy》2022,47(68):29390-29398
With the methods of density functional theory (DFT) and molecular simulations, we have investigated the structural characteristics and hydrogen storage properties of five new reported boron-phosphorus cube based covalent organic frameworks (BP-COFs) with the higher valency. The structural parameters of five BP-COFs were researched by the numeric Monte Carlo (NMC) method, and the hydrogen adsorption properties were studied with grand canonical Monte Carlo (GCMC) simulations under the pressure of 0.1 bar–100 bar at both 77 K and 298 K. The results reveal that BP-COF-4 and BP-COF-5 possess the higher hydrogen adsorption capacities than BP-COF-1 to BP-COF-3 at both 77 K and 298 K. The possible methods to improve the H2 adsorption properties of five BP-COFs are also proposed. We hope this study may provide some reference and inspiration for exploring new COFs with the higher valency as high-performance hydrogen storage materials in future. 相似文献
15.
《International Journal of Hydrogen Energy》2022,47(80):34183-34194
The development of advanced materials for the safety and efficiency of hydrogen storage media is necessary. We computationally explored the hydrogen storage properties of penta-CN2 sheet. The hydrogen adsorption properties of neutral, negatively charged, externally strained, and metal-doped penta-CN2 sheets were investigated in detail. Here, for the first time, the effect of the strain of two-dimensional nonmetallic materials on hydrogen adsorption is investigated. We found that the hydrogen binding energy increases to ?0.20 eV and achieves storage capacities up to 9.00 wt % on the negatively charged substrate, and to ?0.14 eV at 18% stretching. Moreover, metal doping causes hydrogen adsorption energy to increase to ?0.25–0.82 eV. The hydrogen storage capacity of Li-doped defective CN2 sheet is up to 10.90 wt%. Our study may provide new insights into the search for advanced materials for reversible hydrogen storage. 相似文献
16.
《International Journal of Hydrogen Energy》2019,44(59):31192-31203
Hydrogen storage properties of Li-decorated graphene oxides containing epoxy and hydroxyl groups are studied by using density functional theory. The Li atoms form Li4O/Li3OH clusters and are anchored strongly on the graphene surface with binding energies of −3.20 and −2.84 eV. The clusters transfer electrons to the graphene substrate, and the Li atoms exist as Li+ cations with strong adsorption ability for H2 molecules. Each Li atom can adsorb at least 2H2 molecules with adsorption energies greater than −0.20 eV/H2. The hydrogen storage properties of Li-decorated graphene at different oxidation degrees are studied. The computations show that the adsorption energy of H2 is −0.22 eV/H2 and the hydrogen storage capacity is 6.04 wt% at the oxidation ratio O/C = 1/16. When the O/C ratio is 1:8, the storage capacity reaches 10.26 wt% and the adsorption energy is −0.15 eV/H2. These results suggest that reversible hydrogen storage with high recycling capacities at ambient temperature can be realized through light-metal decoration on reduced graphene oxides. 相似文献
17.
Salvador M. Aceves Francisco Espinosa-Loza Elias Ledesma-Orozco Timothy O. Ross Andrew H. Weisberg Tobias C. Brunner Oliver Kircher 《International Journal of Hydrogen Energy》2010
LLNL is developing cryogenic capable pressure vessels with thermal endurance 5–10 times greater than conventional liquid hydrogen (LH2) tanks that can eliminate evaporative losses in routine usage of (L)H2 automobiles. In a joint effort BMW is working on a proof of concept for a first automotive cryo-compressed hydrogen storage system that can fulfill automotive requirements on system performance, life cycle, safety and cost. Cryogenic pressure vessels can be fueled with ambient temperature compressed gaseous hydrogen (CGH2), LH2 or cryogenic hydrogen at elevated supercritical pressure (cryo-compressed hydrogen, CcH2). When filled with LH2 or CcH2, these vessels contain 2–3 times more fuel than conventional ambient temperature compressed H2 vessels. LLNL has demonstrated fueling with LH2 onboard two vehicles. The generation 2 vessel, installed onboard an H2-powered Toyota Prius and fueled with LH2 demonstrated the longest unrefueled driving distance and the longest cryogenic H2 hold time without evaporative losses. A third generation vessel will be installed, reducing weight and volume by minimizing insulation thickness while still providing acceptable thermal endurance. Based on its long experience with cryogenic hydrogen storage, BMW has developed its cryo-compressed hydrogen storage concept, which is now undergoing a thorough system and component validation to prove compliance with automotive requirements before it can be demonstrated in a BMW test vehicle. 相似文献
18.
《International Journal of Hydrogen Energy》2022,47(12):7861-7869
In this article, we have explored the hydrogen (H2) storage capacity of the Li doped B clusters LinB14(n = 1–5) using density functional theory (DFT). The geometrical and Bader's topological parameters indicate that the clusters adsorb H2 in the molecular form. The Li atom polarises the H2 molecules for their effective adsorption on the clusters. The LinB14 (n = 1–5) clusters are found to be stable even after H2 adsorption at room temperature. The average adsorption energy is found to be in the range of 0.12–0.14 eV/H2. Among the various clusters, the Li5B14 shows maximum H2 storage capacity (13.89 wt%) at room temperature. The ADMP simulation reveals that within few femtoseconds (fs), the H2 molecules begin to move away from the clusters and within 400 fs most of the H2 molecules moved away from the clusters. 相似文献
19.
《International Journal of Hydrogen Energy》2019,44(14):7354-7370
New hydrogen adsorption states on Li, Na, and Mg-decorated graphene-type BC3 sheet have been investigated by first-principles calculations. The structural, electronic and binding properties, metal binding and nH2 (n = 1–10) adsorption states of these systems are studied in detail with the Mulliken analysis, charge density differences, and partial density of states. To enhance the number of the adsorbed H2 molecules per metal atom, and also to generate the better initial coordinates for reducing the simulation time, we present two masthematical algorithms (CLICH and RICH). The tested results on BC3 sheet and boron-doped graphene (C30B2) show that these algorithms can increase the number of adsorbed hydrogen molecules by minimizing the computational time. It is seen that nH2 (n = 1–10) adsorbed Li,/Na and/Mg-decorated BC3 single- and double-sided systems are industrial materials for hydrogen storage technology, their adsorption energies fall into the acceptable adsorption energy range (0.20–0.60 eV/H2). It is concluded from the optimized geometries and charge density differences for the higher number of H2 adsorbed systems that not only decorated metal atom but also the sheet plays an important role in hydrogen storage process, because the boron atoms in the sheet expand the induced electric field between the adatoms and BC3 sheet. From Mulliken analysis, there is a charge transfer mechanism between H2 molecules and metal atoms. Moreover, the resonant peaks for the sheet, metal atoms and H2 molecules in partial density of states curves indicate the possible hybridizations. Additionally, these adsorption processes are supported by charge density difference plots. 相似文献
20.
《International Journal of Hydrogen Energy》2022,47(42):18384-18395
The transition away from fossil fuel and ultimately to a carbon-neutral energy sector requires new storage materials for hydrogen and methane as well as new solutions for carbon capture and storage. Among the investigated adsorbents, activated carbons are considered especially promising because they have a high specific surface area, are lightweight, thermally and chemically stable, and easy to produce. Moreover, their porosity can be tuned and they can be produced from inexpensive and environmentally friendly raw materials. This study reports on the development and characterization of activated carbons synthesized starting from amorphous cellulose with and without the inclusion of copper nanoparticles. The aim was to investigate how the presence of different concentrations of metal nanoparticles affects porosity and gas storage properties. Therefore, the research work focused on synthesis and characterization of physical and chemical properties of pristine and metal-doped activated carbons materials and on further investigation to analyze their hydrogen, methane and carbon dioxide adsorption capacity. For an optimized Cu content the microporosity is improved, resulting in a specific surface area increase of 25%, which leads to a H2 uptake (at 77 K) higher than the theoretical value predicted by the Chahine Rule. For CH4, the storage capacity is improved by the addition of Cu but less importantly because the size of the molecule hampers easy access of the smaller pores. For CO2 a 26% increase in adsorption capacity compared to pure activated carbon was achieved, which translated with an absolute value of over 48 wt% at 298 K and 15 bar of pressure. 相似文献