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Sodium alanate (NaAlH4) is a prospective H2 storage material for stationary and mobile applications, as NaAlH4 contains 7.4 wt% of H2, and it is possible to do multiple H2 release and accumulation cycles. Nanoconfinement is a potential solution to enhance the H2 release properties of NaAlH4. To optimize the supporting material and the synthesis method used for the nanoconfinement of NaAlH4, a better understanding of the influence of nanoconfinement on the H2 release processes is necessary. Thus, the H2 release from bulk, purely nanoconfined, and intermediate NaAlH4 is measured at different temperature ramp rates, and the characteristic parameters for each hydrogen release process are determined. Activation energies for each process are determined using the Kissinger method, and the effect of nanoconfinement on the activation energies is analysed. The impact of nanoconfinement on the H2 release processes from NaAlH4 and the limitations of each process in case of bulk and nanoconfined NaAlH4 are presented and discussed. Nanoconfinement of NaAlH4 decreases activation energies of the initial reversible H2 release steps to between 30 and 45 kJ mol−1 and increased the activation energy of the last irreversible H2 release step to over 210 kJ mol−1.

LiAlH4 is a potential solid-state H2 storage material, where safe and efficient H2 storage is of critical importance for the transition towards a sustainable emission-free economy. To improve the H2 release and storage properties of LiAlH4, confinement in porous media decreases the temperature of H2 release and improves the kinetics, where considerably improved H2 release properties are accompanied by a loss in the total amount of H2 released. The capability of mesoporous carbon black to improve the H2 storage properties of confined LiAlH4 is investigated with temperature-programmed desorption and time-stability measurements using X-ray diffraction and N2 gas adsorption measurements to characterize the composite materials’ composition and structure. Here, we present the capability of commercial carbon black to effectively lower the onset temperature of H2 release to that of near-ambient, ≥295 K. In addition, the confinement in mesoporous carbon black destabilized LiAlH4 to a degree that during ≤14 days in storage, under Ar atmosphere and at ambient temperature, 40% of the theoretically contained H2 was lost due to decomposition. Thus, we present the possibility of destabilizing LiAlH4 to a very high degree and, thus, avoiding the melting step before H2 release at around 440 K using scaffold materials with fine-tuned porosities.

Highly microporous adsorbents have been under considerable scrutiny for efficient adsorptive storage of H2. Of specific interest are sustainable, chemically activated, microporous carbon adsorbents, especially from renewable and organic precursor materials. In this article, six peat-derived microporous carbon materials were synthesized by chemical activation with ZnCl2. N2 and CO2 gas adsorption data were measured and simultaneously fitted with the 2D-NLDFT-HS model. Thus, based on the obtained results, the use of a low ratio of ZnCl2 for chemical activation of peat-derived carbon yields highly ultramicroporous carbons which are able to adsorb up to 83% of the maximal adsorbed amount of adsorbed H2 already at 1 bar at 77 K. This is accompanied by the high ratio of micropores, 99%, even at high specific surface area of 1260 m2 g−1, exhibited by the peat-derived carbon activated at 973 K using a 1:2 ZnCl2 to peat mass ratio. These results show the potential of using low concentrations of ZnCl2 as an activating agent to synthesize highly ultramicroporous carbon materials with suitable pore characteristics for the efficient low-pressure adsorption of H2.

Polyethylene terephthalate (PET) tape is widely used by well-known lithium-ion battery manufacturers to prevent electrode stacks from unwinding during assembly. PET tape is selected since it has suitable mechanical and electrical properties, but its chemical stability has been largely overlooked. In the absence of effective electrolyte additives, PET can depolymerize into its monomer dimethyl terephthalate, which is an unwanted redox shuttle that induces substantial self-discharge in a lithium-ion cell. This study presents a chemical screening experiment to probe the PET decomposition mechanism involving in situ generated methanol and lithium methoxide from dimethyl carbonate, one of the most common electrolyte solvents in lithium-ion cells. By screening other polymers, it is found that polypropylene and polyimide (Kapton) are stable in the electrolyte. Finally, it is demonstrated that reversible self-discharge of LiFePO4–graphite cells can be virtually eliminated by replacing PET jellyroll tape with chemically stable polypropylene tape.Polyethylene terephthalate (PET) tape is widely used for lithium-ion batteries but its chemical stability has been largely overlooked. Reversible self-discharge is now shown to be virtually eliminated in LiFePO4–graphite cells by replacing PET with polypropylene jellyroll tape.

Highly microporous adsorbents have been under considerable scrutiny for efficient adsorptive storage of H[sub.2] . Of specific interest are sustainable, chemically activated, microporous carbon adsorbents, especially from renewable and organic precursor materials. In this article, six peat-derived microporous carbon materials were synthesized by chemical activation with ZnCl[sub.2] . N[sub.2] and CO[sub.2] gas adsorption data were measured and simultaneously fitted with the 2D-NLDFT-HS model. Thus, based on the obtained results, the use of a low ratio of ZnCl[sub.2] for chemical activation of peat-derived carbon yields highly ultramicroporous carbons which are able to adsorb up to 83% of the maximal adsorbed amount of adsorbed H[sub.2] already at 1 bar at 77 K. This is accompanied by the high ratio of micropores, 99%, even at high specific surface area of 1260 m[sup.2] g[sup.−1] , exhibited by the peat-derived carbon activated at 973 K using a 1:2 ZnCl[sub.2] to peat mass ratio. These results show the potential of using low concentrations of ZnCl[sub.2] as an activating agent to synthesize highly ultramicroporous carbon materials with suitable pore characteristics for the efficient low-pressure adsorption of H[sub.2] .

Highly microporous adsorbents have been under considerable scrutiny for efficient adsorptive storage of H-2. Of specific interest are sustainable, chemically activated, microporous carbon adsorbents, especially from renewable and organic precursor materials. In this article, six peat-derived microporous carbon materials were synthesized by chemical activation with ZnCl2. N-2 and CO2 gas adsorption data were measured and simultaneously fitted with the 2D-NLDFT-HS model. Thus, based on the obtained results, the use of a low ratio of ZnCl2 for chemical activation of peat-derived carbon yields highly ultramicroporous carbons which are able to adsorb up to 83% of the maximal adsorbed amount of adsorbed H-2 already at 1 bar at 77 K. This is accompanied by the high ratio of micropores, 99%, even at high specific surface area of 1260 m(2) g(-1), exhibited by the peat-derived carbon activated at 973 K using a 1:2 ZnCl2 to peat mass ratio. These results show the potential of using low concentrations of ZnCl2 as an activating agent to synthesize highly ultramicroporous carbon materials with suitable pore characteristics for the efficient low-pressure adsorption of H-2.

LiAlH4 is a potential solid-state H2 storage material, where safe and efficient H2 storage is of critical importance for the transition towards a sustainable emission-free economy. To improve the H2 release and storage properties of LiAlH4, confinement in porous media decreases the temperature of H2 release and improves the kinetics, where considerably improved H2 release properties are accompanied by a loss in the total amount of H2 released. The capability of mesoporous carbon black to improve the H2 storage properties of confined LiAlH4 is investigated with temperature-programmed desorption and time-stability measurements using X-ray diffraction and N2 gas adsorption measurements to characterize the composite materials’ composition and structure. Here, we present the capability of commercial carbon black to effectively lower the onset temperature of H2 release to that of near-ambient, ≥295 K. In addition, the confinement in mesoporous carbon black destabilized LiAlH4 to a degree that during ≤14 days in storage, under Ar atmosphere and at ambient temperature, 40% of the theoretically contained H2 was lost due to decomposition. Thus, we present the possibility of destabilizing LiAlH4 to a very high degree and, thus, avoiding the melting step before H2 release at around 440 K using scaffold materials with fine-tuned porosities.