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A low-concentration (0.5 M) all-fluorinated electrolyte (LCAFE) was designed to stabilize high-energy-density lithium metal batteries. Introducing fluorinated solvents can control the electrolyte's solvation structure, interfacial chemistry, and physicochemical properties. Therefore, this LCAFE has good wettability, nonflammability, and excellent stability for lithium anodes.

MgH2 is considered as a promising hydrogen storage material for on-board applications. In order to improve hydrogen storage properties of MgH2, the amorphous TiMgVNi3-doped MgH2 is prepared by ball milling under hydrogen atmosphere. It is found that the catalytic (Ti,V)H2 and Mg2NiH4 nanoparticles are in situ formed after activation. As a result, the amorphous TiMgVNi3-doped MgH2 exhibits enhanced dehydrogenation kinetics (the activation energy for hydrogen desorption is 94.4 kJ mol−1 H2) and superior cycle durability (the capacity retention rate is up to 92% after 50 cycles). These results demonstrate that the in situ formation of highly dispersed catalytic nanoparticles from an amorphous phase is an effective pathway to enhance hydrogen storage properties of MgH2.

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by progressive neuronal loss in different brain regions, including the dopaminergic (DA) neurons of the substantia nigra pars compacta (SNc). The aggregation of α-synuclein (α-Syn) plays an essential role in the progression of PD-related neuron toxicity. In this study, bioinformatic analysis was used to confirm differentially expressed genes between patients with PD and healthy donors. Immunofluorescence was used to study the aggregation of α-Syn. Flow cytometry was used to confirm the apoptosis of neurons. Western blot was used to investigate the underlying mechanism. Coimmunoprecipitation (co-IP) was used to verify the interaction between proteins. Luciferase activity assay was used to confirm the target gene of miRNA. In vitro protein ubiquitination assay was used to ascertain the role of S-phase kinase-associated protein 1 (SKP1) on the ubiquitination processes of polo-like kinase 2 (PLK2). The result indicated that miR-101-3p was overexpressed in the substantia nigra of the postmortem brains of patients with PD. The underlying role was investigated in the SH-SY5Y cell line. The overexpression of α-Syn did not result in toxicity or aggregation. However, the co-overexpression of miR-101-3p and α-Syn promoted aggregation and neuron toxicity. Luciferase activity assay indicated that SKP1 is a target gene of miR-101-3p. The co-IP experiment confirmed that SKP1 could directly interact with PLK2. In vitro protein ubiquitination assay confirmed that SKP1 could promote the ubiquitination and subsequent protein degradation of PLK2. We also observed that the cotransfection of short hairpin RNA that targets PLK2 and α-Syn overexpression plasmid results in the endoplasmic reticulum stress of neurons. Our results collectively provide evidence that miR-101-3p contributes to α-Syn aggregation in neurons through the miR-101-3p/SKP1/PLK2 pathway.

A new MgH2–PrF3–Al–Ni composite was prepared by ball milling under hydrogen atmosphere. After initial dehydrogenation and rehydrogenation, Pr3Al11, MgF2, PrH3 and Mg2NiH4 nanoparticles formed accompanying the main phase MgH2. The hydrogen absorption-desorption properties were measured by using a Sieverts-type apparatus. The results showed that the MgH2–PrF3–Al–Ni composite improved cycle stability and enhanced hydrogen desorption kinetics. The improvement of hydrogen absorption-desorption properties is ascribed to the synergetic effect of the in situ formed Pr3Al11, MgF2, PrH3 and Mg2NiH4 nanoparticles. This work provides an important inspiration for the improvement of hydrogen storage properties in Mg-based materials.

MgH2 is one of promising hydrogen storage materials due to its high hydrogen capacity of 7.6 wt%. However, MgH2 nanocrystallites easily grow up during hydrogen absorption―desorption cycling, leading to deterioration of hydrogen storage properties. To clarify the growth kinetics of MgH2 crystallites, the growth characteristics of MgH2 nanocrystallites are investigated in this work. The growth exponents of MgH2 nanocrystallites in pure MgH2 and MgH2―10 wt% Pr3Al11 samples are evaluated to be n = 5 and n = 6, respectively. Meanwhile, their activation energies for crystallite growth are also determined to be 109.2 and 144.2 kJ/mol, respectively. The increase of growth exponent and rise of activation energy for crystallite growth in MgH2―10 wt% Pr3Al11 composite are ascribed to the presence of nano-sized Pr3Al11 phase.

MgH2 is one of promising hydrogen storage materials, but Mg crystallites grow up very fast during hydrogen desorption, leading to the degradation of hydrogen storage properties. Therefore the growth behavior and mechanism of Mg crystallites during hydrogen desorption of nanocrystalline MgH2 were investigated in this work. It was found that the transformation from MgH2 to Mg occurred by the surface-controlled ‘nucleation and growth’ mechanism. After the instantaneous nucleation of Mg at free surfaces of MgH2 particles, Mg crystallites grew through three stages, namely one-dimensional, then two-dimensional and finally one-dimensional growths. In the second stage, Mg crystallites grew quickly as compared with other stages. After complete hydrogen desorption, the average Mg crystallite size in MgH2−10 wt% Pr3Al11 sample was smaller than that in pure MgH2 sample due to the presence of Pr3Al11.

In this paper, studies were conducted by a series of single-factor experiments to investigate the effects of ultrasound types and working parameters on the higher alcohols (HA), phenolic compounds, and color properties of red wine, so as to highlight the importance of the comprehensive consideration on its application. The results indicate that ultrasound devices and working parameters do have some definite influences on the HA of wine; moreover, the ultrasound bath (SB-500DTY) is better than the SCIENTZ-950E and the KQ-300VDE. With the SB-500DTY employed to further investigate its effects on phenols and color properties other than on HA, unexpectedly, some variations of color parameters are opposite to the results ever obtained from other ultrasound conditions. In summary, all these results suggest that both the ultrasound type and parameters should be fully considered or neutralized so as to have a comprehensive evaluation about its application, instead of some contradictory results.

Confinement of LiBH4 in porous materials is an efficient route to enhance the ionic conductivity of lithium, which seems to be associated with various types of scaffolding and its mixture ratios. In the present work, we reveal the effect of supports on ionic conductivity improvements based on a comparison of different silica supports, including micro-SiO2 (SM), porous nano-SiO2 (MSN), and nano-SiO2 with nanochannels (SBA-15). All LiBH4/silica composites exhibited higher lithium ionic conductivity, where LiBH4/SBA-15 (47% weight ratio) exhibited the highest conductivity of 3 × 10−5 S cm−1 at 35 °C, nearly three orders of magnitude higher than that of pure LiBH4. In addition, the LiBH4/SBA-15 composite has a wider electrochemical stability window of −0.2 to 5 V, satisfactory compatibility with the Li anode, and no occurrence of side reactions. These ionic conductivity enhancements can be attributed to the support effects of distinct SiO2, i.e., the increase in surface area for superior interfacial ionic conductivity and/or the increased disorder of LiBH4 for faster matrix ionic conductivity. The present study offers useful insights for designing a new hydride solid electrolyte for all-solid-state lithium ion batteries.

Slow hydrogen sorption kinetics is one of the challenges facing practical applications of MgH2. To improve the hydrogen sorption kinetics, an Mg–Pr–Al composite is prepared by ball milling of a 14MgH2 + Pr + Al powder mixture. During hydrogenation and dehydrogenation processes of the Mg–Pr–Al composite, two reversible side reactions, i.e. 2PrH2 + H2 = 2PrH3 and Mg17Al12 + 17H2 = 17MgH2 + 12Al, occur accompanying hydrogen adsorption and desorption of the Mg–H2 system. The in situ formed Pr3Al11 phase in the activated Mg–Pr–Al composite is stable during further hydrogen adsorption and desorption processes, which plays a role in inhibiting growth of Mg crystallites. Hence, the improvement of hydrogen sorption kinetics for the Mg–Pr–Al composite is ascribed to the inhibiting role of Pr3Al11 in crystallite growth as well as the catalytic effect of PrH3/PrH2 on hydrogen sorption. These findings provide an important guidance for developing new Mg-based materials with superior hydrogen storage properties.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive neuronal loss in different brain regions, including the dopaminergic (DA) neurons of the substantia nigra pars compacta (SNc). The aggregation of α-synuclein (α-Syn) plays an essential role in the progression of PD-related neuron toxicity. In this study, bioinformatic analysis was used to confirm differentially expressed genes between patients with PD and healthy donors. Immunofluorescence was used to study the aggregation of α-Syn. Flow cytometry was used to confirm the apoptosis of neurons. Western blot was used to investigate the underlying mechanism. Coimmunoprecipitation (co-IP) was used to verify the interaction between proteins. Luciferase activity assay was used to confirm the target gene of miRNA. In vitro protein ubiquitination assay was used to ascertain the role of S-phase kinase-associated protein 1 (SKP1) on the ubiquitination processes of polo-like kinase 2 (PLK2). The result indicated that miR-101-3p was overexpressed in the substantia nigra of the postmortem brains of patients with PD. The underlying role was investigated in the SH-SY5Y cell line. The overexpression of α-Syn did not result in toxicity or aggregation. However, the co-overexpression of miR-101-3p and α-Syn promoted aggregation and neuron toxicity. Luciferase activity assay indicated that SKP1 is a target gene of miR-101-3p. The co-IP experiment confirmed that SKP1 could directly interact with PLK2. In vitro protein ubiquitination assay confirmed that SKP1 could promote the ubiquitination and subsequent protein degradation of PLK2. We also observed that the cotransfection of short hairpin RNA that targets PLK2 and α-Syn overexpression plasmid results in the endoplasmic reticulum stress of neurons. Our results collectively provide evidence that miR-101-3p contributes to α-Syn aggregation in neurons through the miR-101-3p/SKP1/PLK2 pathway.

Bismuth (Bi) has recently been discovered as a potential lithium-ion anode material for batteries with high Li capacity and suitable equilibrium potential, and without dendrite formation. However, the reversible electrochemical stability remains insufficient for applications. Herein, it is demonstrated that two-dimensional free-standing Bi nanosheets (Bi-NSs) have superior anode performance using either liquid or solid electrolytes. The Bi-NSs with a uniform thickness of ∼40 nm prepared by aqueous methods exhibit a record high capacity of ∼287 mA h g-1 at a current density of 250 mA g-1 with the LiBH4 solid electrolyte even after 100 cycles. Fast and stable solid-state lithium plating and stripping occur without side reactions. The 2D layered nanostructure has more active sites and a shorter diffusion length, and forms stable interfaces with the electrolyte. The present work reveals a facile synthesis route of novel 2D materials and paves an efficient pathway for high-capacity and safe bismuth-based anodes for lithium batteries.

To reveal the synergistic effect of nanoconfinement and metallic catalysis on the hydrogen storage properties of LiBH4, the nanoporous Ni-based alloy (np-Ni) was prepared herein by dealloying of the Mn70Ni30 alloy in (NH4)2SO4 solution, and then LiBH4 was loaded into np-Ni to construct the LiBH4/np-Ni hydrogen storage system using wet impregnation. It was found that dehydrogenation of the LiBH4/np-Ni (1:5) system starts at around 70°C and ends before 400°C, with ~11.9 wt.% of hydrogen desorbed. The apparent dehydrogenation activation energy for the LiBH4/np-Ni (1:5) system was remarkable decreased to about 11.4 kJ/mol. After rehydrogenation at 450°C under 8 MPa hydrogen pressure, ~8.2 wt.% of hydrogen can be released from about 60°C upon second dehydrogenation. These obtained results would provide an efficient strategy for improving the hydrogen storage properties of other metal borohydrides.

Developing cheap metal nanocatalysts with controllable catalytic activity is one of the critical challenges for improving hydrogen storage in magnesium (Mg). Here, it is shown that the activity of graphene-anchored Co–Ni nanocatalysts can be regulated effectively by tuning their composition and morphology, which results in significantly improved hydrogen storage in Mg. The catalytic activity of supported Co–Ni nanocatalysts is demonstrated to be highly dependent on their morphology and composition. When Ni was partly substituted by Co, the shape of these nanocatalysts was changed from spherical to plate-like, thus corresponding to a decrease in activity. These alterations intrinsically result in enhanced hydrogen storage properties of MgH2, i.e., not only does it exhibit a decreased peak desorption temperature but also a positive change in the initial activation for sorption. The results obtained provide a deep understanding of the tuning of catalytic activity via composition and morphology and further provide insights into improving hydrogen storage in Mg-based materials.

Developing cheap metal nanocatalysts with controllable catalytic activity is one of the critical challenges for improving hydrogen storage in magnesium (Mg). Here, it is shown that the activity of graphene-anchored Co–Ni nanocatalysts can be regulated effectively by tuning their composition and morphology, which results in significantly improved hydrogen storage in Mg. The catalytic activity of supported Co–Ni nanocatalysts is demonstrated to be highly dependent on their morphology and composition. When Ni was partly substituted by Co, the shape of these nanocatalysts was changed from spherical to plate-like, thus corresponding to a decrease in activity. These alterations intrinsically result in enhanced hydrogen storage properties of MgH2, i.e., not only does it exhibit a decreased peak desorption temperature but also a positive change in the initial activation for sorption. The results obtained provide a deep understanding of the tuning of catalytic activity via composition and morphology and further provide insights into improving hydrogen storage in Mg-based materials.

In the present study Mg2Ni-type compounds alloyed independently with Ti, V, Fe and Si were successfully prepared by wet-milling followed by sintering. Although these alloyed Mg2Ni compounds exhibited a similar hydrogen storage mechanism as that of pure Mg2Ni, the dissolution of Ti, V or Fe into the Mg2NiH4 lattice had a considerable catalytic effect on hydrogen desorption from additional MgH2. The further structure investigations clearly indicated that the substitution of Ti for Ni could suppress the formation of the micro-twined low-temperature phase (LT2) and promote the formation of the high-temperature phase (HT), thus resulting in remarkably improved hydrogen desorption kinetics for the Mg2Ni0.92Ti0.08–H system. Keywords: Hydrogen storage, Mg-based alloys, Elemental substitution, Kinetics

Achieving rapid hydrogen desorption at low temperatures is one of the main challenges for Mg-based alloys in hydrogen storage. Here, we report that the dehydrogenation process of Mg2NiH4 can be intrinsically improved with the solid dissolution of titanium into its lattices. The hydrogen desorption is suggested to be promoted by shifting the rate-limiting step from proven nucleation and/or diffusion to two-dimensional phase boundary migration based on kinetic modeling studies, for which few additions have been obtained, probably due to the understanding being confounded by other impurity phases. This alteration intrinsically results in enhanced desorption properties of Mg2NiH4 when Ti is dissolved, i.e., not only does it exhibit a decreased peak desorption temperature with a reduction in the activation energy, but it also positively changes the enthalpy value in comparison with that of the pure compound. These obtained results allow for a deep understanding of how the intrinsic desorption features are enhanced by solid dissolution, and also provide insight into improving hydrogen storage in Mg-based alloys.

An uncommon dehydrogenation mechanism for metal chloride-added ammonia borane (NH3BH3, AB) systems revealed that MgCl2 interacts with the [NH3] units in AB, analogous to the amine complex of Mg(NH3)xCl2, thus not only resulting in a remarkable decrease in the hydrogen desorption temperature but also effectively suppressing undesirable volatile by-products, particularly ammonia gas.

The implementation of magnesium (Mg) as a hydrogen-storage medium has long been restricted because of its rather sluggish hydrogen sorption at high temperatures. Here, we report a method for using hydrogen-induced Mg–Zr interfacial coupling to manipulate the migration of hydrogen atoms and thus tune their uptake and release in a micrometer-sized Mg-rich composite. The associated Mg–Zr–H interfaces were assembled in situ by high-pressure ball milling and isothermal treatment of MgH2 and Zr powders under a hydrogen atmosphere. The interfaces gradually disintegrated upon MgH2 desorption but also recovered their original compositions upon absorption while the ZrH2 originating from Zr hydrogenation remained completely unchanged. Compared to pure MgH2, the hydrogen sorption of the Mg–Zr–H composite was thus shown to be dramatically faster at lower temperatures, whereby it not only absorbed hydrogen close to saturation at 100 °C within 2 h, while the pure Mg did not absorb hydrogen at all, but also started to release hydrogen at ∼235 °C with a reduction in the activation energy of desorption by ∼40 kJ mol−1. These remarkable enhancements cannot be explained by the decrease in the size of the MgH2 grains alone but are most likely due to the introduction of Mg–Zr–H interfaces and large fractions of defects that provide channels for facile hydrogen dissociation and migration into the Mg/MgH2 matrix.

Hepatocellular carcinoma (HCC) is a common cancer that affects people worldwide with high morbidity and mortality, and its resistance to current chemotherapeutic drugs is a serious concern. Cytotoxicity of silica nanoparticles (Nano-SiO2) towards cancer cells has been reported previously, but the specific mechanism is not fully clear. In this study, Nano-SiO2 showed a remarkable cytotoxic effect against HCC cells, regardless of whether the cells were drug resistant or not. Further study showed that Nano-SiO2 treatment leads to cell cycle arrest, apoptosis enhancement and necroptosis induction in the HCC cells. RNA-seq data, together with bioinformatics analysis, revealed that a series of genes involved in cancer cell death could be regulated by Nano-SiO2, among which ZBP-1 was up-regulated the most by Nano-SiO2 treatment. The siRNA based experiments demonstrated that ZBP-1 might play a key role in mediating Nano-SiO2 cytotoxic functions against HCC cells. These results have evidently signified the anti-tumor potential of Nano-SiO2 in the treatment of HCC.

The realization of the facile and green synthesis of low-dimensional nanomaterials is critical not only for energy storage but also for catalysis. A selective aqueous corrosion strategy is presented here for obtaining low-dimensional metals, including nanoparticles, nanofibers and nanosheets, based on the dealloying of aqueous-favoring metal from its bulk alloy.

Slow hydrogen sorption kinetics is one of the challenges facing practical applications of MgH

Mg2FeH6- and Mg2CoH5-based composites with in situ formed YH3 and Mg2NiH4 nanoparticles were synthesized by ball milling of Mg10YNi + 4Fe (in mole ratio) and Mg10YNi + 4Co powders, respectively, at 4 MPa H2 followed by hydrogenation at 673 K for 60 h under a hydrogen pressure of 7 MPa. It is found that the nanocrystalline YH3 and Mg2NiH4 particles are indeed embedded in Mg2FeH6 and Mg2CoH5 matrixes. The hydrogen desorption rates of Mg2FeH6- and Mg2CoH5-based composites are enhanced compared to those undoped Mg2FeH6 and Mg2CoH5 hydrides, respectively, due to the synergetic catalysis of nanosized YH3 and Mg2NiH4 particles. This finding provides us with an efficient and simple approach for the improvement in hydrogen desorption kinetics of Mg-based hydrogen storage materials.

The advantage of potassium–magnesium bimetallic hydride as novel destabilization agent for LiNH2 is demonstrated by a comparative study among MgH2-, NaMgH3-, and KMgH3- systems. LiNH2 combined with KMgH3 not only results in a substantial decreased desorption temperature by >60 °C and suppression of NH3 release but also enhances sorption kinetics two to five times in comparison with the single MgH2 or NaMgH3. A high reversible capacity of >65% is also achieved, even recharging under milder conditions. Through detailed structural analysis on the desorption products in various stages of these combined systems, we proposed a “self-concerted” reaction mechanism in which the in situ formed active MgH2 and KH by KMgH3 are involved in LiNH2 decomposition. In addition, the remarkable promotion in conveyance of N-containing species by highly active KH compared with NaH is believed to be responsible for the superior destabilizing effect of KMgH3 over NaMgH3 in improving hydrogen sorption kinetics of LiNH2.

The NaBH4 nanocrystals (NCs) were successfully synthesized by mechanically driven anion metathesis between LiBH4 and NaCl where the newly formed NaBH4 has an approximately 10 nm in size being in situ embedded in the buffering matrix of LiCl byproduct. These NaBH4 NCs obtained show significantly enhanced desorption properties with a reduction in onset temperature by 30%, over 6 times faster kinetics and nearly 4 times higher equilibrium pressure than those of micro-NaBH4. This novel mechanochemical approach can also be employed to prepare other borohydrides NCs such as KBH4.

To understand the effect of [RNi5]/[RMgNi4] unit ratio on hydrogen storage properties of layered R–Mg–Ni compounds, the hydrogen absorption–desorption characteristics of Sm–Mg–Ni compounds have been investigated comparatively in this work. As the [SmNi5]/[SmMgNi4] unit ratio increases, the parameters of [SmNi5] and [SmMgNi4] units in layered Sm2MgNi9, Sm3MgNi14, and Sm4MgNi19 compounds decrease gradually, leading to the elevation of equilibrium pressure, enlargement of slope, and reduction of hysteresis of their P–C isotherms as well as the decline of enthalpy change for hydrogen absorption–desorption. The hydrogen capacities of the layered Sm–Mg–Ni compounds at 298 K are higher than those of SmMgNi4 and SmNi5, and the cycle stability can be improved by the increase of [SmNi5]/[SmMgNi4] unit ratio.

Ti–Cr–Mn-based alloys with a C14-type Laves structure have been investigated for potential application in hybrid high-pressure metal hydride tanks for fuel cell vehicles. The effects of partial substitution of Ti by Zr, and of Cr by Mo and W, on the hydrogen storage properties of Ti–Cr–Mn-based alloys have been systematically investigated. Among these alloys, (Ti 0.85 Zr 0.15 ) 1.1 Cr 0.9 Mo 0.1 Mn shows the best overall properties, with a hydrogen desorption pressure and capacity of 9.54 atm and 1.78 wt% at 0 °C. The kinetics and cycling stability are also discussed for on-board hybrid high-pressure metal hydride tank applications. According to calculations, the volumetric H 2 density of the hybrid system can reach the Department of Energy (DOE) 2017 target, while its gravimetric density remains at a high value of 2.72 wt% when 28% of the inner volume in a hybrid hydrogen metal hydride tank is filled with this alloy.

The dehydrogenation enthalpy change of MgH2 by reversibly forming an Mg0.95In0.05 solid solution offers a new method for tuning the thermodynamics of Mg-based alloys. In order to further lower the stability of MgH2, Al has been introduced into Mg(In) solid solution. At the same time, to solve the problem of sluggish kinetic properties of Mg–In solid–solution systems and to lower the dehydrogenation activation energy, Ti has also been added. It has been demonstrated that the Mg85In5Al5Ti5 alloy synthesized by plasma milling (P-milling) shows both enhanced dehydriding thermodynamics and kinetics. This technique could be used to synthesize Mg(In, Al) ternary solid solution incorporating the Ti catalyst in only one step, making it much more efficient than the two-step method. Compared with Mg-based solid solutions, the addition of Ti and in-situ synthesized MgF2 improved the kinetics and the introduction of In as well as Al imparted enhanced thermodynamics to the Mg85In5Al5Ti5 system. The dehydrogenation enthalpy change and activation energy were lowered to 65.2 kJ/(mol H2) and 125.2 kJ/mol, respectively, for the Mg85In5Al5Ti5 alloy.

A comparative study of Mg5.7In0.3Ag and Mg6Ag alloys was conducted to reveal the effects of indium (In) solid solutions on the hydrogen storage properties of Mg-based alloys. Different from the Mg6Ag alloy, the as-cast Mg5.7In0.3Ag alloy was composed of a Mg(In) solid solution and Mg3Ag. However, an initial hydrogen absorption/desorption treatment (i.e., activation) propelled the In atoms in Mg(In) toward Mg3Ag, forming (Mg, In)3Ag in the activated sample. This transformation involving the dissolution of In atoms from Mg into solid Mg3Ag not only greatly improved the thermodynamics of hydrogen desorption but also enhanced its catalytic effect on hydrogen desorption from additional MgH2. The (Mg, In)3Ag–H2 system exhibited altered thermodynamics, as its enthalpy change of the hydrogen desorption was 62.6 kJ mol−1 H2. Moreover, the activation energy of the hydrogen desorption from the Mg5.7In0.3Ag sample was lowered to 78.2 kJ mol−1.

For the first time, component segregation during cycling was demonstrated to be responsible for the deterioration in the kinetics of bimetallic hydride NaMgH3. To solve this problem, we propose a method involving in situ embedding of Mg2NiH4 and YH3 into NaMgH3, which is accomplished with a solid-phase reaction using amorphous Mg12YNi alloy and NaH as starting materials under a H2 atmosphere. Using this novel method, 12 wt % of the Mg2NiH4 phase and 11 wt % of the YH3 phase were homogeneously embedded in the NaMgH3 matrix. In comparison to those of pure NaMgH3, this composite material exhibits no change in thermodynamics but shows greatly enhanced kinetics for hydrogen absorption and desorption cycling. In addition, reasonable mechanisms for the enhanced kinetics have been proposed including the prevention of macroscopic segregation of metallic Na, grain refinement, and a synergistic catalytic effect. All of these mechanisms rely on the intimately interdispersed Mg2NiH4 and YH3 nanoparticles embedded in t...

This paper presents a new approach to tune the de/hydriding thermodynamic properties of Mg via forming reversible Mg base solid solutions in the Mg–In and Mg–In–Al systems by mechanical milling. The effect of solubility of In and Al on the reversible formation of solid solution structure and hydrogen storage properties were investigated. It is found that although the solute atoms unavoidably are rejected upon hydriding, the hydrogenated products of MgH2 and intermediate MgIn compound could fully transform back to solid solution after dehydrogenation. In the hydriding of Mg(In, Al) ternary solid solution, Al would get dissolved into MgIn compound rather than forming free Al like the Mg(Al) binary solid solution. Therefore, the presence of In improves the dehydriding reversibility of Mg(Al) solid solution, and the reversible Al concentration could be increased up to the 8 at. %, which is just the solubility limit of Al in Mg by mechanical milling. The reversible phase transformation is responsible for the r...

A new approach was developed to successfully load Mg into the nanometre-sized pores of an anodic aluminium oxide (AAO) template for realizing the nano-confinement of Mg. Structural characterization shows that Mg nano-particles are nucleated along the AAO pipe wall together with the formation of MgO and Mg17Al12 as by-products. The flow rate of argon gas, the temperature of the AAO template and the transporting distance between the Mg vapour source and the AAO template were optimized to achieve the confinement of Mg nano-particles with larger loading rate. Under optimized deposition conditions, the particle size of the loaded Mg is less than 100 nm and the effective filling factor is about 35 wt%. The confined Mg/MgH2 even after 10 de-/hydrogenation cycles still shows favourable kinetics. Furthermore, the slight reduction in hydrogen desorption enthalpy and entropy of MgH2 from (74.42 ± 0.12) to (73.21 ± 0.04) kJ·mol−1 and (130.98 ± 0.05) to (130.11 ± 0.24) J·mol−1·K−1 is also found in the present nano-confinement.

The Ca3Mg2Ni13 unit cell can be viewed as the stacking of three blocks along the c axis. Each block is composed of two sub-blocks; one sub-block contains one layer of a [CaMgNi4] unit, and the other sub-block consists of one layer of a [CaMgNi4] unit and one layer of a [CaNi5] unit. To understand the deuterium release from the Ca3Mg2Ni13 deuteride, crystal structures of Ca3Mg2Ni13D15.6, Ca3Mg2Ni13D5.9, and Ca3Mg2Ni13D0.3 corresponding to before, during, and after deuterium desorption were determined by neutron diffraction. In Ca3Mg2Ni13D15.6, D atoms occupy interstitial sites within [CaNi5] and [CaMgNi4] units as well as sites at two unit borders. Upon deuterium desorption, the D atoms located at unit borders are released first. Then D atoms located within [CaNi5] and [CaMgNi4] units are simultaneously released which leads to the coexistence of Ca3Mg2Ni13D5.9 and a deuterium-poor solid solution phase. With further desorption, Ca3Mg2Ni13D5.9 transforms into Ca3Mg2Ni13D0.3 where D atoms reside in [CaNi5] un...

Herein, a self-assembly strategy for the realization of diverse light metal complex borohydride nanoparticles (NPs) with sphere, polygon and hollow geometries is presented. Under ambient conditions, the particle sizes of the LiBH4 NPs formed can easily be controlled by varying the concentration which enables hydrogen gas release at ∼72 °C.

In this work, the hydrogen absorption and desorption properties of a melt-spun Mg86Pr3Al11 alloy were studied using a Sieverts-type apparatus. It was found that the melt-spun Mg86Pr3Al11 alloy exhibits an enhanced cycle durability of hydrogen absorption and desorption. After fifty hydrogen absorption and desorption cycles at 300 °C, the capacity retention rate is about 97% and the hydrogen sorption kinetics undertakes only a slight degradation, which is related to the existence of PrAl2 and Pr3Al11 phases in the melt-spun Mg86Pr3Al11 alloy.

A comparative study was conducted to reveal the effect of microstructure on hydrogen permeation in the EA4T and 30CrNiMoV12 railway axle steels. Unlike the EA4T with its sorbite structure, 30CrNiMoV12 steel shows a typical tempered martensitic structure, in which a large number of fine, short, rod-like, and spherical carbides are uniformly dispersed at boundaries and inside laths. More importantly, this structure possesses plentifully strong hydrogen traps, such as nanosized Cr7C3, Mo2C, VC, and V4C3, thus resulting in a high density of trapping sites (N = 1.17 &times, 1022 cm&minus, 3). The hydrogen permeation experiments further demonstrated that, compared to EA4T, the 30CrNiMoV12 steel not only delivered minimally effective hydrogen diffusivity but also had a high hydrogen concentration. The activation energy for hydrogen diffusion of the 30CrNiMoV12 steel was greatly increased from 23.27 &plusmn, 1.94 of EA4T to 47.82 &plusmn, 2.14 kJ mol&minus, 1.