共查询到20条相似文献,搜索用时 15 毫秒
1.
《International Journal of Hydrogen Energy》2019,44(45):24829-24838
Owing to the existence of periodic channels in phosphorene, this 2D material can be a good candidate for room temperature reversible hydrogen storage. The density functional theory calculations (DFT), including van der Waals interactions (vdW-DF2) coupled with the cooper exchange functional (C09), has been applied to study the potential of phosphorene as a new 2D material for hydrogen storage. Our results show that the adsorption energy (−292 to −277 meV) of H2 on phosphorene is appropriate for storage. The analysis of diffusion pathways between different physisorbed states on phosphorene shows that a single hydrogen molecule diffuses very easily along the open channel (less than 1 meV along the zigzag direction), as compared to 14 meV for diffusion across the channels (along the armchair direction). The potential energy surfaces for the dissociative chemisorption of H2 was computed on highly symmetric sites of phosphorene and the highest activation barrier was found to be 2.77 eV. The very large dissociation energy coupled with a strong physisorption of H2 on phosphorene and facile diffusion, makes this 2D material a promising candidate for H2 storage at room temperature. 相似文献
2.
《International Journal of Hydrogen Energy》2022,47(61):25696-25703
In this work, we report on the study of the hydrogen storage capability of titanium (Ti) decorated B36 nanosheets using density functional theory (DFT) calculations with van der Waals corrections. Ti atoms are strongly bonded to the surface of B36 with a binding energy of 6.23 eV, which exceeds the bulk cohesive energy of crystalline Ti. Ti-decorated B36 (2Ti@B36) can reversibly adsorb up to 12 H2 molecules with a hydrogen storage capacity of 4.75 wt % and average adsorption energy between 0.361 and 0.674 eV/H2. The values of desorption temperature and the results of molecular dynamics simulations enable to conclude that 2Ti@B36 is a perspective reversible material for hydrogen storage under real conditions. 相似文献
3.
Taking into account the van der Waals correction, the characteristics of the Li-decorated graphyne as the hydrogen storage medium have been explored using first-principles plane wave calculations. We find that Li atom can be adsorbed not only over the center of large hexagon (HL site) but also over the center of small hexagon (HS site). For double-side Li decorations, there are 14H2 molecules can be adsorbed on Li-decorated graphyne primitive cell with the adsorption energy of 0.19 eV/H2. As a result, the hydrogen storage capacity of 13.0 wt% can be obtained. This suggests that the Li-decorated graphyne system can serve as a high-capacity hydrogen storage medium. 相似文献
4.
Puspamitra Panigrahi Dilip Acharya Sheeba Rathina Selvi Rajeev Ahuja Tanveer Hussain 《International Journal of Hydrogen Energy》2021,46(38):19988-19997
There is a great interest in the design of innovative concepts and strategies of nitrogen rich carboneous materials for exploring their hydrogen (H2) storage properties. Methane (CH4) storage can be an alternative to H2 because the combustion energy of the former is around three times higher than the latter. However, strong inter-molecular repulsion between the CH4 molecules is a major bottleneck to achieve a high gravimetric density. In this study, we use first principles density functional calculations to investigate the coadoption of H2 and CH4 on Li decorated carbon nitride (Li–C7N6) monolayer. The repulsion between CH4 molecules has been avoided by keeping them in asymmetric configuration whereas the repulsion between CH4–H2 is in moderation due to the exploitation of open Li doped sites on C7N6 surface. Though Li–C7N6 has a lower H2 or CH4 storage capacity due to weak van der Waals interactions, the capacity could be doubled with a novel strategy of co-mixing of H2 with CH4 which results into a significantly high gravimetric density of 8.1 wt%. This clearly shows that the CH4–H2 co-mixing strategies have the potential to further propel the prospects of C7N6 monolayers for reversible clean energy storage applications. 相似文献
5.
Yusheng Wang Rui Zheng Haiyan Gao Jing Zhang Bin Xu Qiang Sun Yu Jia 《International Journal of Hydrogen Energy》2014
Hydrogen storage properties of 10 different adatom decorated silicene are carried out using density functional theory calculations with long-range van der Waals dispersion correction. It is found that the binding energy between metal adatoms and the silicene is greater than the cohesive energy of bulk metal so that clustering of adatom will not occur once it is bonded with silicene. The adsorption of H2 on Li, Na, K, Mg, Ca, and Au decorated silicene is a weak physisorption. Differently, a weaker chemisorption is responsible for the adsorption of H2 on Be, Sc, Ti, and V decorated silicene. In particular, silicene with Na, K, Mg, and Ca decorating on both sides leads to 7.31–9.40 wt% hydrogen storage capacity with desirable adsorption energy, indicating that the metal-decorated silicene can serve as a high capacity hydrogen storage medium. 相似文献
6.
《International Journal of Hydrogen Energy》2020,45(29):14907-14914
Hydrogen has become a strong candidate to be a future energy storage medium but there are technological challenges both in its production and storage. For storage, a search for lightweight, abundant and non-toxic materials is on the way. An abundant natural material such as wood cellulose would make an ideal storage medium from a sustainability perspective. Here, using a combination of static DFT calculations and ab initio molecular dynamics simulations at different temperatures, it is shown that wood cellulose has the ability to uptake H2 via a physisorption mechanism based on dispersion interactions of the van der Waals type involving the O-atoms of the d-glucose rings. The absorption causes little to no disturbances on the cellulose structure and H2 is highly mobile in the material. At an external pressure of H2(g) of 0.09 atm and T = 25 °C, cellulose has a theoretical gravimetric density of hydrogen storage of ≈1%. 相似文献
7.
《International Journal of Hydrogen Energy》2021,46(56):28700-28708
The mechanism of hydrogen molecule adsorption on 2D buckled bismuthene (b-Bi) monolayer decorated with alkali metal atoms was studied using density functional theory based first principles calculations. The decorated atoms Li, Na and K exhibited distribution on surface of b-Bi monolayer with increasing binding energy of 2.6 eV, 2.9 eV and 3.6 eV respectively. The adsorption of H2 molecule on the slabs appeared stable which was further improved upon inclusion of van der Waals interactions. The adsorption behaviour of H2 molecules on the decorated slabs is physisorption whereas the slabs were able to bind up to five H2 molecules. The average adsorption energy per H2 molecules are in range of 0.1–0.2 eV which is good for practical applications. The molecular dynamics simulation also confirmed the thermodynamic stabilities of five H2 molecules adsorbed on the decorated slabs. The storage capacity values are found 2.24 wt %, 2.1 wt %, and 2 wt %, for respective cases of Li, Na and K atoms decorated b-Bi. The analysis of the adsorbed cases pointed to electrostatic interaction of Li and H2 molecule. The adsorption energies, binding energies, charge analysis, structural stability, density of states, and hydrogen adsorption percentage specifies that the decorated b-Bi may serve as an efficient hydrogen storage material and could be an effective medium to interact with hydrogen molecules at room temperature. 相似文献
8.
The adsorption behavior of hydrogen molecules on the calcium-decorated BC7 sheet has been investigated using first-principles calculations. Our calculations demonstrate that the van der Waals interactions are crucial for the hydrogen storage in the calcium-decorated BC7 sheet. We find that the average adsorption energy per hydrogen molecules decreases with the number of adsorbed hydrogen molecule increasing. When six hydrogen molecules adsorb, the average adsorption energy is 0.26 eV. In this case, the gravimetric density for hydrogen storage on two sides of calcium-decorated BC7 sheet is about 4.96 wt%. These features indicate that the calcium-decorated BC7 sheet has potential application in hydrogen storage. 相似文献
9.
《International Journal of Hydrogen Energy》2022,47(14):8929-8942
Underground hydrogen storage can store grid-scale energy for balancing both short-term and long-term inter-seasonal supply and demand. However, there is no numerical simulator which is dedicated to the design and optimisation of such energy storage technology at grid scale. This study develops novel simulation capabilities for GPSFLOW (General Purpose Subsurface Flow Simulator) for modelling grid-scale hydrogen and gas mixture (e.g., H2–CO2–CH4–N2) storage in cavern, deep saline aquifers and depleted gas fields.The accuracy of GPSFLOW is verified by comparisons against the National Institute of Standard and Technology (NIST) online thermophysical database and reported lab experiments, over a range of temperatures from 20 to 200 °C and pressure up to 1000 bar. The simulator is benchmarked against an existing model for modelling pure H2 storage in a synthetic aquifer. Several underground hydrogen storage scenarios including H2 storage in a synthetic salt cavern, H2 injection into a CH4-saturated aquifer experiment, and hydrogen storage in a depleted gas field using CO2 as a cushion gas are used to test the GPSFLOW's modelling capability. The results show that GPSFLOW offers a robust numerical tool to model underground hydrogen storage and gas mixture at grid scale on multiple parallel computing platforms. 相似文献
10.
《International Journal of Hydrogen Energy》2020,45(11):6780-6792
We computationally investigate the hydrogen storage properties of carbyne C10-ring structure on either Dnh or D(n/2)h symmetry decorated with calcium (Ca) atoms adsorbed on its outer surface. The calculations are carried out on DFT-GGA-PW91 and DFT-GGA-PBE levels of theory as implemented in Biovia Materials Studio modeling and simulation software. To account for van der Waals interactions we also carried out calculations using DFT-D method of Grimme. Dmol3 is used to calculate total energies, HOMO-LUMO electronic charge density, Mulliken population analysis, and electrostatic potential fitting charges (ESP). Based on these results: i) the average binding energy of Ca atom doping to C10-ring is ~2.3 eV (PW91) and ~2.1 eV (PBE). ii) Up to seven H2 molecules per Ca atom can be physically adsorbed with an average energy of ~0.2 eV per H2 molecule. iii) This physisorption leads to 8.09 wt percentage (wt. %) for the gravimetric storage capacity. According to these results, calcium-decorated carbyne C10-ring structure is excellent candidate for hydrogen storage at ambient conditions with application to fuel cells. 相似文献
11.
《International Journal of Hydrogen Energy》2020,45(29):14915-14921
Hydrogen storage in clathrate hydrates is a promising approach for industry-scale utilizations. However, extreme operation conditions such as high pressure (about GPa) limit the development. In this work hydrogen hydrate phase equilibrium in addition of methane, tert-butyl alcohol (tBA), trichloromethane (CHCl3) and 1,1-dichloro-1-fluoroethane (HCFC-141 b) are reported at 6 MPa–20 MPa and 274 K–286 K, which including 21 points in total. Mechanism studies using Raman spectroscopy show that tBA and H2O form metastable hydrate cages via hydrogen bonds, then form stable sII hydrates with the help of CH4. Hydrate-based hydrogen storage capacity in 5.6 mol%HCFC-141 b-water mixture could reach 46 V/V (0.36 wt%) at 273 K and 10 MPa. Combing with chemical energy of HCFC-141 b, this work achieved high capacity of hydrogen and chemical energy storage in gas hydrate at mild conditions. This study will provide guidance on hydrate-chemical hybrid hydrogen storage technology, and leads to the next generation of hybrid hydrate-based hydrogen technology in the future. 相似文献
12.
《International Journal of Hydrogen Energy》2022,47(99):41833-41847
By applying density functional theory (DFT) and ab-initio molecular dynamics (AIMD) simulations, we predict the ultrahigh hydrogen storage capacity of K and Ca decorated single-layer biphenylene sheet (BPS). We have kept various alkali and alkali-earth metals, including Na, Be, Mg, K, Ca, at different sites of BPS and found that K and Ca atoms prefer to bind individually on the BPS instead of forming clusters. It was found that 2?2?1 supercell of biphenylene sheet can adsorb eight K, or eight Ca atoms, and each K or Ca atom can adsorb 5H2, leading to 11.90% or 11.63% of hydrogen uptake, respectively, which is significantly higher than the DOE-US demands of 6.5%. The average adsorption energy of H2 for K and Ca decorated BPS is ?0.24 eV and ?0.33 eV, respectively, in the suitable range for reversible H2 storage. Hydrogen molecules get polarized in the vicinity of ionized metal atoms hence get attached to the metal atoms through electrostatic and van der Waals interactions. We have estimated the desorption temperatures of H2 and found that the adsorbed H2 can be utilized for reversible use. We have found that a sufficient energy barrier of 2.52 eV exists for the movement of Ca atoms, calculated using the climbing-image nudged elastic band (CI-NEB) method. This energy barrier can prevent the clustering issue of Ca atoms. The solidity of K and Ca decorated BPS structures were investigated using AIMD simulations. 相似文献
13.
Potassium-doped PC71BM for hydrogen storage: Photoelectron spectroscopy and first-principles studies
De-Qu Lin Long-Xi Wang Cheng-Hui Song Ying-Ying Du Guang-Hua Chen Chen Liu Jia-Ou Wang Rui Wu Hai-Jie Qian Kurash Ibrahim Hong-Nian Li 《International Journal of Hydrogen Energy》2021,46(24):13061-13069
We consider the fullerene C70 derivative PC71BM as a potential onboard hydrogen storage material. As the cases of many sorbents, metal-decoration is needed to increase the adsorption energy of H2. We study the metal-decoration by intercalating K atoms into a PC71BM film and performing photoelectron spectroscopy measurements. The results reveal that the maximum stoichiometry is K9–10PC71BM. Then we study the hydrogen storage property of an isolated K9PC71BM molecule with density functional theory calculations. A K9PC71BM molecule can compactly adsorb 45H2 (6.22 wt%); the compact adsorption structure does not require large interstitial space in solid phase and thus should be able to be realized in experiments. Considering the poor crystallinity of solid PC71BM (with many large interstitial spaces), a gravimetric capacity >7 wt% can be anticipated. The adsorption energy meets the DOE target of onboard operating temperatures, and van der Waals interaction contributes more than 40% of the adsorption energy. 相似文献
14.
《International Journal of Hydrogen Energy》2022,47(44):19168-19174
The boron-based two-dimensional (2D) materials decorated with functional groups NLi4 has been numerically investigated for hydrogen storage via first principles calculations method. Strain-energy analysis and molecular dynamics simulations shows the pristine planar honeycomb B2O has strong mechanical and thermal stability. Crystal Orbital Hamiltonian Population analysis confirmed that there exist stronger B–B/B–O covalent bonds within B2O monolayer. In functional material, a local electric field around each lithium atom can be formed and the overall electronic structure is favorably changed for gas adsorptions. Both electrostatic forces and the van der Waals interaction are the dominant hydrogen-attached mechanisms of lithium cation. An anchored functional group NLi4 can adsorb at most 11 hydrogen molecules, and the average adsorption energy per hydrogen molecules is around ?0.20 eV, indicating high hydrogen storage capacity and reversible applicability. The highest hydrogen storage capacity can reach to 9.1 wt%. The study shows the investigated material is a good candidate for hydrogen storage. 相似文献
15.
High-capacity reversible hydrogen storage properties of metal-decorated nitrogenated holey graphenes
《International Journal of Hydrogen Energy》2022,47(19):10654-10664
Motivated by the need for an effective way of storing hydrogen (H2), a promising energy carrier, we have performed density functional theory (DFT) calculations with different van der Waals corrections coupled with the statistical thermodynamic analysis and ab initio molecular dynamics (AIMD) on the light-metal decorated nitrogenated holey graphene (C2N) monolayers. We have found that the decoration by selected light metals (Na, Mg, Ca) improves the H2 adsorption on the C2N to the desired levels (>150 meV/H2). Moreover, the metal dopants strongly bonded with C2N even at higher doping concentrations, which invalidates the metal clusters formation. Among considered metals, Na and Mg resulted in H2 storage capacities of 5.5 and 6.9 wt%, respectively, which exceed the target set by the U.S. Department of Energy's for 2025. Thermodynamic analysis and the AIMD simulations were employed to investigate the H2 sorption at varied conditions of temperature and pressure for practical applications. 相似文献
16.
《International Journal of Hydrogen Energy》2023,48(32):12036-12044
This work analysed the permeation of binary and ternary H2-containing mixtures through a SAPO-34 membrane, aiming at investigating how hydrogen influences and its permeation is influenced by the presence of the other gaseous species, such as CO2 and CH4. We considered the behaviour of various gas mixtures in terms of permeability and selectivity at various temperatures (25–300 °C), feed pressures (400–1000 kPa) and compositions by means of an already validated mass transport model, which is based on surface and gas translation diffusion. We found that the presence of CO2 and CH4 in the H2-containing mixtures influences in a similar way the H2 permeation, reducing its permeability of about 80% compared to the single-gas value because of their stronger adsorption. On the other hand, H2 promotes the permeation of CO2 and CH4, causing an increment of their permeability with respect to those as single gases. These combined effects reflected in interesting selectivity values in binary mixture (e.g., CO2/H2 about 11 at 25 °C, H2/CH4 about 9 at 180 °C), which showed the potential of SAPO-34 membranes in treating of H2-containing mixtures. 相似文献
17.
《International Journal of Hydrogen Energy》2019,44(31):16348-16358
Mesoporous g-C3N4/Zn–Ti layered double hydroxide (LDH)-laminated van der Waals heterojunction nanosheets were prepared by a facile one-step in situ hydrothermal method. Due to the strong electrostatic interactions between the positively charged Zn–Ti LDH and negatively charged g-C3N4 nanocrystal, a laminated van der Waals heterostructure was successfully formed between Zn–Ti LDH and g-C3N4. The mesoporous g-C3N4/Zn–Ti LDH-laminated van der Waals heterojunction, which had a narrow bandgap of 2.41 eV extended the photoresponse to the visible light region. The obtained heterojunctions showed excellent visible-light-driven photocatalytic performance for the complete removal of ceftriaxone sodium (up to ∼97%) and a high hydrogen production rate (∼161.87 μmol h−1 g−1). This was mainly attributed to the formation of the laminated van der Waals heterojunctions, which favoured charge separation and the absorption of visible light, and the mesoporous structure, which provided more surface active sites. This facile strategy for preparing mesoporous g-C3N4/Zn–Ti LDH-laminated van der Waals heterojunctions offers new insights for the fabrication of high-performance van der Waals heterojunction photocatalytic materials. 相似文献
18.
Sudhanshu S. Pawar Valentine Nkongndem Nkemka Ahmad A. Zeidan Marika Murto Ed W.J. van Niel 《International Journal of Hydrogen Energy》2013
A two-step, un-coupled process producing hydrogen (H2) from wheat straw using Caldicellulosiruptor saccharolyticus in a ‘Continuously stirred tank reactor’ (CSTR) followed by anaerobic digestion of its effluent to produce methane (CH4) was investigated. C. saccharolyticus was able to convert wheat straw hydrolysate to hydrogen at maximum production rate of approximately 5.2 L H2/L/Day. The organic compounds in the effluent collected from the CSTR were successfully converted to CH4 through anaerobic digestion performed in an ‘Up-flow anaerobic sludge bioreactor’ (UASB) reactor at a maximum production rate of 2.6 L CH4/L/day. The maximum energy output of the process (10.9 kJ/g of straw) was about 57% of the total energy, and 67% of the energy contributed by the sugar fraction, contained in the wheat straw. Sparging the hydrogenogenic CSTR with the flue gas of the UASB reactor ((60% v/v) CH4 and (40% v/v) CO2) decreased the H2 production rate by 44%, which was due to the significant presence of CO2. The presence of CH4 alone, like N2, was indifferent to growth and H2 production by C. saccharolyticus. Hence, sparging with upgraded CH4 would guarantee successful hydrogen production from lignocellulosic biomass prior to anaerobic digestion and thus, reasonably high conversion efficiency can be achieved. 相似文献
19.
《International Journal of Hydrogen Energy》2022,47(40):17835-17844
TeO2, as a promising gas sensor material, has been extensively studied for its capacity to detect hydrogen with high sensitivity. First-principles calculations were applied to explore the adsorption properties of hydrogen (H2), carbon dioxide (CO2), methane (CH4), and hydrogen sulfide (H2S) on TeO2 doped with either Mg or Mn to explore this compound's potential as hydrogen sensors. Hydrogen is more readily adsorbed on pure-TeO2, Mg–TeO2 and Mn–TeO2 than CO2, CH4 and H2S molecules by calculating their adsorption energy and charge transfer; the sequence of adsorption strength is H2>H2S > CO2>CH4. The hydrogen molecules and pure-TeO2, Mg–TeO2 and Mn–TeO2 form H–O bonds with lengths of 0.98, 0.98 and 0.99 Å, respectively, indicating that chemical adsorption is dominant between them. The adsorption of hydrogen leads to significant changes in the density of states (DOSs) of pure-TeO2, Mg–TeO2 and Mn–TeO2, which may lead to changes in their electrical conductivity. Moreover, the larger diffusion coefficients for hydrogen on the surfaces of pure-TeO2, Mg–TeO2 and Mn–TeO2 relative to other gases indicates that hydrogen diffuses readily in TeO2-based sensing materials, and the higher gas concentration contributes to improvements in response performance. This finding offers a theoretical basis for experimental explorations of the influence of metal dopants on TeO2 hydrogen sensing performance. 相似文献
20.
Zhaoshun Meng Ruifeng Lu Dewei Rao Erjun Kan Chuanyun Xiao Kaiming Deng 《International Journal of Hydrogen Energy》2013
Based on the first-principles derived force fields and grand canonical Monte Carlo simulations, we find that the catenated metal-organic frameworks outperform the noncatenated structures, in terms of H2 separation from other gases (CH4, CO and CO2) and H2 adsorption by Li doping. A system utilizing IRMOF-11 (or IRMOF-13) for hydrogen separation and Li-doped IRMOF-9 for hydrogen storage is therefore proposed, with hydrogen uptake of 4.91 wt% and 36.6 g/L at 243 K and 100 bar for Li-doped IRMOF-9, which is close to the 2017 DOE target. It is promising to find appropriate microporous materials for hydrogen purification and storage at ambient conditions with structure catenated. 相似文献