Search

In all‐solid‐state batteries, a solid electrolyte with high ionic conductivity is required for fast charging, uniform lithium deposition, and increased cathode capacity. Lithium argyrodite with BH4− substitution has promising potential due to its higher ionic conductivity compared to argyrodites substituted with halides. In this study, Li5.25PS4.25(BH4)1.75, characterized by a high ionic conductivity of 13.8 mS cm−1 at 25 °C, is synthesized via wet ball‐milling employing o‐xylene. The investigation focused on optimizing wet ball‐milling parameters such as ball size, xylene content, drying temperature, as well as the amount of BH4− substitution in argyrodite. An all‐solid‐state battery prepared using Li5.25PS4.25(BH4)1.75 as the electrolyte and LiNbO3 coated NCM811 as the cathode exhibits an initial coulombic efficiency of 90.2% and maintains 93.9% of its initial capacity after 100 cycles at fast charging rate (5C). It is anticipated that the application of this wet mechanochemical synthesis will contribute further to the commercialization of all‐solid‐state batteries using BH4‐substituted argyrodites. [ABSTRACT FROM AUTHOR]

Hydrogen‐driven energy is fascinating among the everlasting energy sources, particularly for stationary and onboard transportation applications. Efficient hydrogen storage presents a key challenge to accomplishing the sustainability goals of hydrogen economy. In this regard, solid‐state hydrogen storage in nanomaterials, either physically or chemically adsorbed, has been considered a safe path to establishing sustainability goals. Though metal hydrides have been extensively explored, they fail to comply with the set targets for practical utilization. Recently, MXenes, both in bare form and hybrid state with metal hydrides, have proven their flair in ascertaining the hydrides′ theoretical and experimental hydrogen storage capabilities far beyond the fancy materials and current state‐of‐the‐art technologies. This review encompasses the significant accomplishments achieved by MXenes (primarily in 2019–2024) for enhancing the hydrogen storage performance of various metal hydride materials such as MgH2, AlH3, Mg(BH4)2, LiBH4, alanates, and composite hydrides. It also discusses the bottlenecks of metal hydrides for hydrogen storage, the potential use of MXenes hybrids, and their challenges, such as reversibility, H2 losses, slow kinetics, and thermodynamic barriers. Finally, it concludes with a detailed roadmap and recommendations for mechanistic‐driven future studies propelling toward a breakthrough in solid material‐driven hydrogen storage using cost‐effective, efficient, and long‐lasting solutions. [ABSTRACT FROM AUTHOR]

The intermittent nature of renewable energy generation can be tackled by integrating them with electrochemical energy storage, which can also close the gap between supply and demand effectively. It has recently been demonstrated that Si3N4‐based negative electrodes are a promising option for lithium‐ion batteries due to their large theoretical capacity and appropriate working potential with extremely low polarization. In the present work, Si3N4 was utilized as anode material in all‐solid‐state lithium‐ion battery with lithium borohydride as a solid electrolyte and Li foil placed as a counter electrode. The electrochemical properties were investigated using galvanostatic charge/discharge profiling whereas the mechanism of lithiation delithiation was investigated in detail using x‐ray diffraction (XRD). The highest capacity of the composite materials was obtained as 1700 mAhg−1 at 0.05 C current rate in the first cycle, which is reduced to 370 in 5 cycles. However, a stability in the capacity was observed in subsequent cycles and a retention of almost 88% could be achieved in 150 cycles. The interfacial resistance before and after the electrochemical cycling was observed as 326 Ω and 13 kΩ, respectively which is also supported by the microstructural investigations where the cracks are observed because of thermochemical reactions. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Utilizing cutting-edge computational screening methods, this study explores the hydrogen storage capacity of two complex metal hydrides, Cs 2 CaH 4 and Rb 2 CaH 4. We perform a thorough analysis of their structural, electrical, optical, and hydrogen storage properties using density functional theory (DFT). Within the I 4/ mmm space group, both compounds display stable tetragonal crystal structures, and their thermodynamic stability is confirmed by their formation energies. Notably, compared to Rb 2 CaH 4 , Cs 2 CaH 4 is more stable. With band gaps of 2.99 eV for Cs 2 CaH 4 and 3.28 eV for Rb 2 CaH 4 , the electronic properties show insulating behavior, which is beneficial for reducing electronic interference during hydrogen absorption and desorption. A comparative research reveals that the potential gravimetric hydrogen storage capacities of Cs 2 CaH 4 (1.28%) and Rb 2 CaH 4 (1.86%) are comparable to, albeit marginally less than, those of materials that are frequently explored, such as lithium borohydride. With their individual absorption and reflectivity peaks, the optical characteristics offer more information about how they interact with electromagnetic radiation, information that may be useful for improving their performance in real-world applications. Our results imply that Cs 2 CaH 4 and Rb 2 CaH 4 have considerable potential for use in practical hydrogen storage systems, especially in situations where stability and minimal electronic interference are essential. Subsequent research endeavors may concentrate on enhancing the hydrogen storage capacity of these materials, so rendering their incorporation into existing hydrogen storage methods more feasible. • Comprehensive computational screening of Rb 2 CaH 4 and Cs 2 CaH 4 for hydrogen storage applications. • Detailed analysis of structural, electronic, and optical properties using DFT calculations. • Rb 2 CaH 4 and Cs 2 CaH 4 exhibit high thermodynamic stability and suitable insulating properties. • Promising gravimetric hydrogen storage capacities: 1.86% for Rb 2 CaH 4 and 1.28% for Cs 2 CaH 4. [ABSTRACT FROM AUTHOR]

Mesoporous alumina (MA) materials with outstanding textural properties have been synthesized by a facile approach, and were evaluated as supports of Pt-based catalyst for methylcyclohexane dehydrogenation. At 300 °C, the resultant catalyst demonstrates a much higher activity with a maximum hydrogen evolution rate of 2081 mmol/g Pt /min in comparison with the state-of-the-art alumina supported Pt catalysts. Interestingly, even after a long-time reaction of 100 h or regeneration, more than 80% of original activity was still maintained. The superior catalytic performance of the obtained catalyst is associated with the high specific surface area and large mesoporous size of support MA, thus benefiting the increase in the number of Pt active sites and efficiently inhibiting the formation of coke deposition during the reaction. Our contribution has provided a rational design strategy for highly efficient and stable dehydrogenation catalysts, which is a key for the utilization of methylcyclohexane-toluene system in hydrogen storage technology. [Display omitted] • A confined hydrolysis-condensation approach. • Mesoporous alumina with excellent textural properties. • Pt-based catalyst with highly homogenous dispersion of Pt. • Improved catalytic performance for dehydrogenation of methylcyclohexane at low temperature. [ABSTRACT FROM AUTHOR]

The first examples of tetrasubstituted conjugated bis‐guanidinate (CBG) supported monomeric and thermally stable gallium dihalides [LGaX2], (X=Cl (Ga−Cl), I (Ga−I)) and dihydride (Ga−H) [LGaH2] (where L={(ArHN)(ArN)−C=N−C=(NAr)(NHAr)}; Ar=2,6‐Et2−C6H3) compounds are reported. The reaction of in situ generated LLi with 1.0 equiv. GaX3 (X=Cl, I) afforded compounds Ga−Cl and Ga−I. The reaction between Ga−Cl and Li[HBEt3] in benzene yielded the dihydride compound Ga−H. All reported compounds (Ga−Cl, Ga−I, and Ga−H) were characterized by NMR, HRMS, and single‐crystal X‐ray diffraction studies. Ga−H was probed for the hydroboration of carbodiimides (CDI), isocyanates, and isothiocyanates with HBpin. Compound Ga−H was also found effective for the catalytic hydroboration of imines, nitriles, alkynes, esters, and formates, affording the corresponding products in quantitative yields. Stoichiometric reactions with a CDI were performed to establish the catalytic cycle. [ABSTRACT FROM AUTHOR]

Ammonia borane (AB) with 19.6 wt % H2 content is widely considered a safe and efficient medium for H2 storage and release. Co‐based nanocatalysts present strong contenders for replacing precious metal‐based catalysts in AB hydrolysis due to their high activity and cost‐effectiveness. However, precisely adjusting the active centers and surface properties of Co‐based nanomaterials to enhance their activity, as well as suppressing the migration and loss of metal atoms to improve their stability, presents many challenges. In this study, mesoporous‐silica‐confined bimetallic Co−Cu nanoparticles embedded in nitrogen‐doped carbon (CoxCu1−x@NC@mSiO2) were synthesized using a facile mSiO2‐confined thermal pyrolysis strategy. The obtained product, an optimized Co0.8Cu0.2@NC@mSiO2 catalyst, exhibits enhanced performance with a turnover frequency of 240.9 molH2 ⋅ molmetal ⋅ min−1 for AB hydrolysis at 298 K, surpassing most noble‐metal‐free catalysts. Moreover, Co0.8Cu0.2@NC@mSiO2 demonstrates magnetic recyclability and extraordinary stability, with a negligible decline of only 0.8 % over 30 cycles of use. This enhanced performance was attributed to the synergistic effect between Co and Cu, as well as silica confinement. This work proposes a promising method for constructing noble‐metal‐free catalysts for AB hydrolysis. [ABSTRACT FROM AUTHOR]

This paper addresses the urgent need for efficient hydrogen storage methods in the context of combating climate change and transitioning to sustainable energy sources. Among various storage options, LiBH 4 is highlighted for its high volumetric and gravimetric energy densities, critical factors in determining its suitability for energy applications. However, challenges arise due to its high thermolysis temperature, which poses difficulties, especially in applications like automotive use where high temperatures are required. The commercial viability of LiBH 4 remains a significant obstacle due to the nascent stage of chemical hydride technology and the absence of large-scale production facilities. Environmental concerns also loom large, as the production of LiBH 4 relies on extensive mining of lithium and boron, known for their environmental impact. Furthermore, the economic feasibility of LiBH 4 as a hydrogen storage medium is questioned, given the substantial portion of total expenses attributed to hydrogen costs, affecting all methods except those based on fossil fuels or electricity. Nevertheless, there is optimism that with technological advancements and improved infrastructure, the costs associated with LiBH 4 and hydrogen storage overall may decrease over time. In conclusion, while LiBH 4 presents promising energy density characteristics, its practical implementation faces challenges such as high production costs, environmental concerns, and technological limitations. Overcoming these obstacles is crucial for realizing a sustainable and carbon-free energy landscape driven by hydrogen. • LiBH 4 shows promise for high energy density storage but faces obstacles high production costs and environmental concerns. • A comprehensive decision matrix analysis showcases the strengths and weaknesses of various hydrogen storage options. • LiBH 4 may find applications in small-scale personal storage due to its safety and energy density. [ABSTRACT FROM AUTHOR]

Indirect reductive amination of aromatic aldehydes was studied in this work; aqueous ammonia was used as a nitrogen source. The results showed that aromatic aldehydes' reaction with aqueous ammonia produced compounds known as hydrobenzamides (N,N´-(phenylmethylene)bis(1-phenylmethanimines), having good yield. The reaction of hydrobenzamides with sodium borohydride reduced both imine and aminal carbons and produced a primary and secondary benzylamine mixture. This article analyses such behaviour and proposes a possible mechanism for explaining such transformation. The reaction of aromatic aldehydes with aqueous ammonia produced compounds known as hydrobenzamides (N,N´-(phenylmethylene)bis(1-phenylmethanimines). The reaction of hydrobenzamides with sodium borohydride reduced both imine and aminal carbons and produced a primary and secondary benzylamine mixture. [ABSTRACT FROM AUTHOR]

The document is a contents list for the New Journal of Chemistry, a publication by The Royal Society of Chemistry. It features papers on various topics such as boron nitride-carbon composites, organic/inorganic artificial bones, and metal-organic frameworks. The journal aims to connect the world with the chemical sciences. The document also includes corrections to previous publications. [Extracted from the article]

Graphene oxide (GO) and transition metal complexes are two well-studied systems owing to their diverse applications and superior properties. Herein, GO/Fe3O4 nanostructure was prepared and used as a support for grafting Schiff base-Cu complex. This novel nanocatalyst was synthesized through modification of GO using Schiff base-Cu complex [GO/Fe3O4/Schiff base-Cu] being an eco-friendly, convenient and cost-effective procedure. The product was studied by various characterization techniques whose results revealed that the copper complex was grafted on the surface of the magnetic graphene oxide. The obtained nanocomposite shows chemical and thermal stabilities, as well as significant catalytic behavior. GO/Fe3O4/Schiff base-Cu nanocomposite was investigated as an efficient catalyst in the reduction of 4-nitrophenol and dyes, including methylene blue (MB) and Congo red (CR) with sodium borohydride in room temperature and aqueous solution by checking the reaction progress via visible–ultraviolent spectroscopy. Also, the catalytic activity of the novel nanocatalyst was evaluated in Knoevenagel condensation and Michael-type addition for the preparation of 2-amino 4H-chromene in ethanol/water green solvent at the temperature of 60 °C. The results showed that the synthesized nanocatalyst isolated magnetically can be reused for 4 times with no remarkable loss in the product yield. The synthesis method employed here demonstrated mainly the advantages of being ecofriendly and simple, excellent yields and high efficiency, usage of non-toxic solvent, as well as easiness of product isolation using ethanol. [ABSTRACT FROM AUTHOR]

Atomic layer deposition was applied on mesoporous silica to synthesize a highly dispersed gallium oxide catalyst. This system was used as starting material to investigate different loadings of nickel in the dehydrogenation of propane under industrially relevant, Oleflex‐like conditions. The formation of NiGa alloys was confirmed by X‐ray diffraction analysis and electron microscopy. Surprisingly, the nanoalloys enhanced the selectivity towards C3H6 while decreasing the tendency for coking. Herein, in situ thermogravimetry, and measured mass fractions of carbon revealed that the coking rate was reduced by over 50 % compared to the pristine gallium oxide. Generally, the increased selectivity can be explained by the partial hydrogenation and reduction of the gallium oxide surface. The optimum temperature for the removal of deposited carbon was evaluated by a temperature programmed oxidation. Finally, the best‐performing Ni−GaOx catalyst was employed in a cycled experiment with periodic reaction and regeneration tests. After regeneration, the selected Ni−GaOx catalyst provided a higher yield of propylene compared to the unmodified gallium oxide. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes a range of articles on various topics such as cross-coupling of alcohols, the structure of CO2 in silica adsorbents, transdermal delivery of insulin, and the design of Zn2+ complexes for chemo-selective hetero-coupling of alcohols. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document also mentions approved training courses offered by the society. [Extracted from the article]

The hexagonal high-temperature form of LiBH4 is known as a fast ion conductor. Here, we investigated its suitability as a solid electrolyte in high-temperature all-solid-state cells when combined with the following active materials: Li metal, graphite, lithium titanium oxide (Li4Ti5O12, LTO), and nanocrystalline rutile (TiO2). First results using lithium anodes and rutile nanorods as cathode material show that a cell constructed by simple cold-pressing operates at reversible discharge capacities in the order of 125 mA h g−1 at a C-rate of C/5 and at temperatures as high as 393 K. Besides TiO2, the compatibility of the LiBH4 with other active materials such as graphite and LTO was tested. We found evidence of possible interface instabilities that manifest through rare, yet still detrimental, self-charge processes that may be relevant for hydrogen storage applications. Moreover, we investigated the long-term cycling behavior of the cells assembled and demonstrate the successful employment of LiBH4 as an easily processable model solid electrolyte in practical test cells. [ABSTRACT FROM AUTHOR]

An attractive option for the storage of hydrogen is the reversible hydrogenation of an aromatic substance, a so‐called liquid organic hydrogen carrier. For hydrogen release, it is desirable to find substances with low enthalpies of reaction for dehydrogenation. It has been demonstrated that substitution, e.g., with methyl groups, on the ring can have a positive effect in this regard. In this study, thermochemical properties of methoxy‐substituted pyridines and quinolines and their respective hydrogenated counterparts have been analyzed from a thermodynamic point of view. Combustion calorimetry has been utilized to measure the enthalpy of formation and the transpiration method for determining the vapor pressure. Additionally, high‐level quantum‐chemical approaches have been applied to obtain caloric data in the gas phase, which provide a basis for comparison and evaluation of the experimental data. The results reveal two main effects of methoxy substitution. First, oxygenated substituents like methoxy groups have stronger effect on the Gibbs energy of reaction and thus the temperature needed thermodynamically for hydrogen release than methyl groups. Second, the effect is highly depending on the position of the substitution on the ring. Particularly methoxy groups close to a N heteroatom can have a significant positive effect, which might enable hydrogen release at equilibrium temperatures more than 50 K lower than for their unsubstituted analogue. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Azo compounds are versatile in multifarious areas. They are crucial reagents in Mitsunobu reactions and dehydrogenations. However, the azo compounds or their corresponding hydrazides have never been investigated in the catalytic dehydrogenation of tertiary amines. Herein, we report a co-catalytic system using CuCl, 4-(dimethylamino)pyridine (DMAP), and 2-(4-nitrophenyl)hydrazine-1-carboxylate for the aerobic oxidative dehydrogenation of tertiary indolines to their corresponding indoles. [ABSTRACT FROM AUTHOR]

A catalyst‐free 1,2‐diborylation of aryllithium with tetra(o‐tolyl)diborane(4) has been achieved, giving a series of 1,2‐diborylaryl lithium species in excellent yields under mild reaction conditions, which leads to 1,2‐di(tolyl)borylarenes in 60–91 % yields upon treatment with the hydride‐abstracting reagent. In these transformations, one sp2 C−H of arene is activated and both boryl units are utilized to build two new (sp2)C−B bonds. This represents a new strategy for selective arene diborylation. Density functional theory (DFT) calculations suggest that an aromatic nucleophilic substitution is a key step in the formation of the products. [ABSTRACT FROM AUTHOR]

The size‐dependent activity of catalysts has been researched for a long time in the field of catalysis. Positively charged small Pt clusters enhance catalytic activity than bigger clusters and bulk for propane dehydrogenation. We performed DFT calculations on small Pt clusters adsorbed on silica support. The planar structure of Pt clusters is present till 4 Pt atoms, after which three‐dimensional structures are observed. AIMD and DFT calculations for silica showed that it has a high surface area and thermal stability suitable to conduct dehydrogenation reactions. The adsorption of Pt cluster on silica results in the formation of directional bonds which affects the properties of the adsorbed Pt catalysts by changing the redox properties. In the bulk phase, ethane and propane molecules undergo dehydrogenation reactions with 0.133 eV atom−1 and 0.244 eV atom−1 energies, respectively. NEB calculations showed that except for Pt‐2/SiO2, all the even Pt clusters require less activation energy than the neighboring odd Pt clusters. Ethane molecule interacting with Pt‐4/SiO2, Pt‐5/SiO2, Pt‐6/SiO2, and propane with Pt‐3/SiO2, Pt‐4/SiO2, Pt‐5/SiO2, Pt‐6/SiO2, follows the reverse Horiuti–Polanyi mechanism during dehydrogenation, whereas non‐reverse Horiuti–Polanyi mechanism (which requires comparatively lower activation energy) is followed for smaller Pt clusters. [ABSTRACT FROM AUTHOR]

The dehydrogenation of propane over Pt supported on Ga-doped silica was investigated, using various meso- and microporous silica supports. The addition of a small amount of Ga (0.5 wt%) to SBA-15 was enough to boost the resultant 1 wt% Pt catalyst's conversion from < 5 up to 38%. Propene selectivity also increased from around 60 to 98%. Optimisation of the Pt and Ga content revealed that low loadings of both active components are necessary to increase the efficiency of the reaction and beyond this only modest improvements in performance were obtained. A range of pore structures were investigated, but the Ga content was found to be more important than the support morphology; without sufficient Ga incorporation into the support the catalyst could not achieve high conversion and selectivity. Post-reaction analysis suggested that coke formation blocking sites was the most likely explanation for catalyst deactivation. These results show that doping Ga into SiO2 as a support for Pt nanoparticles is a viable strategy for producing highly efficient catalysts for propane dehydrogenation. [ABSTRACT FROM AUTHOR]

The effect of particle size and support on the catalytic performance of supported subnanometer copper clusters was investigated in the oxidative dehydrogenation of cyclohexene. From among the investigated seven size-selected subnanometer copper particles between a single atom and clusters containing 2–7 atoms, the highest activity was observed for the titania-supported copper tetramer with 100% selectivity toward benzene production and being about an order of magnitude more active than not only all the other investigated cluster sizes on the same support but also the same tetramer on the other supports, Al2O3, SiO2, and SnO2. In addition to the profound effect of cluster size on activity and with Cu4 outstanding from the studied series, Cu4 clusters supported on SiO2 provide an example of tuning selectivity through support effects when this particular catalyst also produces cyclohexadiene with about 30% selectivity. Titania-supported Cu5 and Cu7 clusters supported on TiO2 produce a high fraction of cyclohexadiene in contrast to their neighbors, while Cu4 and Cu6 solely produce benzene without any combustion, thus representing odd–even oscillation of selectivity with the number of atoms in the cluster. [ABSTRACT FROM AUTHOR]

Hydrogen plays a crucial role in the future energy landscape owing to its high energy density. However, finding an ideal storage material is the key challenge to the success of the hydrogen economy. Various solid‐state hydrogen storage materials, such as metal hydrides, have been developed to realize safe, effective, and compact hydrogen storage. However, low kinetics and thermodynamic stability lead to a high working temperature and a low hydrogen sorption rate of the metal hydrides. Using scaffolds made from porous materials like silica to confine the metal hydrides is necessary for better and improved hydrogen storage. Therefore, this article reviews porous silica‐based scaffolds as an ideal material for improved hydrogen storage. The outcome showed that confining the metal hydrides using scaffolds based on porous silica significantly increases their storage capacities. It was also found that the structural modifications of the silica‐based scaffold into a hollow structure further improved the storage capacity and increased the affinity and confinement ability of the metal hydrides, which prevents the agglomeration of metal particles during the adsorption/desorption process. Hence, the structural modifications of the silica material into a fibrous and hollow material are recommended to be crucial for further enhancing the metal hydride storage capacity. [ABSTRACT FROM AUTHOR]

In the present work, single, double and triaxial (tensile/compression) strains were applied to lithium borohydride LiBH 4 using Density Functional Theory (DFT) based on Perdew-Burke-Ernzerhor for solids (PBEsol) approach. The results show that the structural properties change with the deformation amplitude. The total density of state (TDOS) and partial density of state (PDOS) studies show that the LiBH 4 complex hydride is an insulator with an energy band gap of 6.73 eV and the width of the valence and conduction bands vary with the change of the strain amplitude. The deformation energy shows that triaxial deformation on LiBH 4 complex hydride requires more energy than single and double strains. Hence, these deformations are found responsible for the decrease of the thermodynamic properties of LiBH 4 hydride. Specifically, under a maximum uni/bi/triaxial compressive strain of ε = −9%, the enthalpy of formation and decomposition temperature decrease by 3.25 %, 7.59 %, and 36.54 %, respectively. While, under a maximum uni/bi/triaxial tensile strain of ε = +9 %, the enthalpy of formation and decomposition temperature decrease by 3.85 %, 11.83 %, and 26.44 %, respectively, compared to unstrained hydride. Consequently, the findings are in excellent agreement with the standards of the U.S. Department of Energy (DOE) (ΔH f = −40 Kj/mol.H 2 and T d = 289–393 K) for hydrogen storage in the solid state. • Study of the thermodynamic properties of LiBH 4 under deformation conditions. • Compressive deformation improves the hydrogen storage performances of LiBH 4. • The results comply with the criteria imposed by the DOE (Department of Energy) for practical applications of H 2 storage. [ABSTRACT FROM AUTHOR]

This study developed a novel approach to ammonia borane (AB) and silica assembly for all-solid-state thermal dehydrogenation, which can be integrated into current hydrogen generation systems. The AB/silica assembly apparatus is created by attaching pelletized AB specimens to both sides of a polyimide film heater, thus facilitating direct heat supply. The temperature, pressure, and power consumption data of the heater demonstrate that the dehydrogenation reaction is completed within 2 min from the initiation of the electric heating signal. Notably, the temperature and pressure of the generated hydrogen gas reach 39.5 °C and 1.95 barg, respectively, and the maximum hydrogen yield reached 11.46 wt% during the experiment. The infrared spectroscopy analysis indicates that all AB/silica samples inside the assembly undergoes complete reaction. This direct heating method significantly reduces the energy required for AB thermal decomposition and it increases the amount of AB that can be used at once. • All-solid-state thermal decomposition enables generation of large amounts of H 2. • Ammonia borane (AB) and silica were used for thermal dehydrogenation. • AB/silica pellets were attached to a polyimide film heater to create the assembly. • The AB/silica assembly made it possible to facilitating direct heat supply. • The direct heating reduced the energy required for thermal dehydrogenation. [ABSTRACT FROM AUTHOR]

The development of efficient catalysts for the dehydrogenation of formic acid (FA) through molecular level control and precise regulation remains challenging. Herein, we report the newly developed complexes of iridium and ruthenium with nitrogen‐rich ligand for aqueous FA dehydrogenation. The Cp*Ir complex 1 (Cp*=cyclopentadienyl) and Ru(p‐cym) complex 2 (p‐cym=p‐Cymene) were synthesized and fully characterized. The single crystal structures of these complexes have a typical piano‐stool structure. A turnover frequency of 12468 h−1 was achieved for FA dehydrogenation at 90 °C by using complex 1 bearing 3,3'‐diamino‐5,5'‐bis(1H‐1,2,4‐triazole) (DABT). The effects of pH, temperature, concentration of formic acid and amount of catalyst on the reaction kinetics were studied in detail. Kinetic isotope effect (KIE) experiments and 1H NMR detection of reaction revealed that a plausible mechanism involves the decarboxylation of formate and the formation of H2. More importantly, the influence of H2O and H+ was involved in the rate‐determining step. This study demonstrated the effectiveness of nitrogen‐rich ligand for FA dehydrogenation, which would contribute to the development of new and effective hydrogen release systems. [ABSTRACT FROM AUTHOR]

This paper highlights the hydrogen storage performance of surface oxidized LiBH 4 (Lithium borohydride) system incorporated with NiO nanostructures under 250 °C. Surface oxidized LiBH 4 system was impregnated with hydrothermally synthesized mesoporous NiO nanorods (NiONR) and NiO nanoplates (NiONP) using simple ultrasonication method. Hydrogen sorption and desorption studies has been investigated for LiBH 4 /NiONR and LiBH 4 /NiONP systems for the first time. The Brunauer-Emmett-Teller results showed that the specific surface area of NiONR, NiONP, LiBH 4 /NiONR and LiBH 4 /NiONP systems were 77.92, 88.12, 96.67 and 101.65 m2/g, respectively. Hydrogenation followed by isothermal dehydrogenation at 250 °C revealed that the LiBH 4 /NiONR and LiBH 4 /NiONP systems released ∼3.44 wt% and 4.02 wt% of hydrogen respectively in 60 min. Using the Kissinger's relation, the activation energy (E a) was calculated as 69.28 and 63.23 kJ/mol for LiBH 4 /NiONR and LiBH 4 /NiONP systems, respectively. The dehydrogenation rate of LiBH 4 /NiONP system was found to be greater than that of LiBH 4 /NiONR system due to its large surface area and lower activation energy. The reported results revealed that nickel oxide nanostructures incorporated surface oxidized LiBH 4 systems provide new opportunities for the solid-state hydrogen storage applications. [Display omitted] • Hydrogen sorption/desorption studies were investigated for the LiBH 4 /NiO systems. • The surface area of LiBH 4 /NiONR and LiBH 4 /NiONP are 96.7 and 101.6 m2/g respectively. • LiBH 4 /NiONP and LiBH 4 /NiONR desorb 4.0 and 3.4 wt% of hydrogen at 250 °C in 1 h. [ABSTRACT FROM AUTHOR]

The present work gives the hydrogen dissociation energies and electronic structures of Li 8−x Ti x B 8 F y H 32−y (x, y = 0 or/and 1) compounds by first-principles density functional theory calculations, with the aim of providing new insights into the enhanced dehydrogenation of LiBH 4 with Ti or/and F additives. The results indicate that substituting more electronegative elements Ti for Li or/and F for H helps to destabilize LiBH 4 , resulting in decreased hydrogen dissociation energies for favorable H-desorption. This is particularly obvious for LiBH 4 sample with Ti + F co-substitution, and associated with the decrease of Li–B, Li–H and B–H bonding interactions, the formation of Ti–B, Ti–H and Li–F bonds, as well as the presence of metallic character. Our work suggests that combined metal cation and nonmetal anion co-doping could effectively modify the properties of LiBH 4 , which is useful for hydrogen storage applications. [Display omitted] • Li 8−x Ti x B 8 F y H 32−y compounds are introduced by Ti substitution for Li or/and F for H. • Synergistic effect of Ti + F co-doping on enhanced dehydrogenation of LiBH 4 is achieved. • LiBH 4 held by weaker Li–B/H and B–H interactions enjoys favorable H-desorption. • Formation of Ti–B/H and Li–F bonds in Li 8−x Ti x B 8 F y H 32−y bulk favors for H-desorption. [ABSTRACT FROM AUTHOR]

The CO2-assisted oxidative dehydrogenation of propane (ODP) was investigated over titania based composite metal oxides, 10% MxOy-TiO2 (M: Zr, Ce, Ca, Cr, Ga). It was found that the surface basicity of composite metal oxides was significantly higher than that of bare TiO2 and varied in a manner which depended strongly on the nature of the MxOy modifier. The addition of metal oxides on the TiO2 surface resulted in a significant improvement of catalytic performance induced by a synergetic interaction between MxOy and TiO2 support. Propane conversion and propylene yield were strongly influenced by the nature of the metal oxide additive and were found to be superior for the Cr2O3-TiO2 and Ga2O3-TiO2 catalysts characterized by moderate basicity. The reducibility of the latter catalysts was significantly increased, contributing to the improved catalytic performance. This was also the case for the surface acidity of Ga2O3-TiO2 which was found to be higher compared with Cr2O3-TiO2 and TiO2. A general trend was observed whereby catalytic performance increased significantly with decreasing the primary crystallite size of TiO2. DRIFTS studies conducted under reaction conditions showed that the adsorption/activation of CO2 was favored on the surface of composite metal oxides. This may be induced by the improved surface basicity observed with the MxOy addition on the TiO2 surface. The Ga2O3 containing sample exhibited sufficient stability for about 30 h on stream, indicating that it is suitable for the production of propylene through ODP with CO2 reaction. [ABSTRACT FROM AUTHOR]

In this study, a Co/MMT catalyst was synthesized by pillaring method using montmorillonite (MMT) as a support material for hydrogen production by hydrolysis reaction from sodium borohydride (NaBH4) solution. N2 sorption, XRD, SEM-EDS, and FTIR spectroscopy techniques were used for catalyst characterization. To optimize the amount of hydrogen obtained as a result of the hydrolysis reaction, the NaBH4 concentration (0.3-0.5 M), the sodium hydroxide (NaOH) concentration (0.3-0.5 M), the amount of catalyst (20-50 mg) and the reaction temperature (30-50 °C) were invesigated. The optimal conditions obtained from the Box-Behnken analysis were 50 °C, 0.33 M NaBH4, 39 mg catalyst, 0.46 M NaOH, and the maximum reaction rate (hydrogen production) was 2328 mL min-1 gcat -1at standard temperature and pressure (298K,1atm). According to the analysis of variance, it was found that all parameters had a significant effect on the hydrogen production rate. [ABSTRACT FROM AUTHOR]

Heterogeneous catalytic ammoxidation provides an eco‐friendly route for the cyanide‐free synthesis of nitrile compounds, which are important precursors for synthetic chemistry and pharmaceutical applications. However, in general such a process requires high pressures of molecular oxygen at elevated temperatures to accelerate the oxygen reduction and imine dehydrogenation steps, which is highly risky in practical applications. Here, we report an electric field enhanced ammoxidation system using a supported Fe clusters catalyst (Fe/NC), which enables efficient synthesis of nitriles from the corresponding aldehydes under ambient air pressure at room temperature (RT). A synergistic effect between the external electric field and the Fe/NC catalyst promotes the ammonia activation and the dehydrogenation of the generated imine intermediates and avoids the unwanted backwards reaction to aldehydes. This electric field enhanced ammoxidation system presents high efficiency and selectivity for the conversion of a series of aldehydes under mild conditions with high durability, rendering it an attractive process for the green synthesis of nitriles with fragile functional groups. [ABSTRACT FROM AUTHOR]

The pure V3+ species boosted the high-efficiency dehydrogenation of V/γ-Al 2 O 3 catalyst. [Display omitted] The vanadium-based dehydrogenation (DH) catalyst is becoming a promise alternative to the industrial used Pt- and Cr-based catalysts, due to lower cost and less environmental threat. However, the low DH activity hampered the industrial application of vanadium-based catalysts. Herein, for the first time, we introduce a method to prepare high-efficiency vanadium-based catalyst by constructing pure V3+ species on γ-Al 2 O 3 through treatment of as-prepared thiovanadate. The V3+ species contributes to not only enhancing the DH activity, but also fabricating the V3+-O/S acid-base pair with ideal strength and stability. The isobutene yield can reach as high as 56.9 wt%. Only Lewis acid is recognized on V3+/Al 2 O 3 catalyst, while no Brønsted acid remains. The side-reactions are consequently inhibited, and the selectivity to isobutene is improved. Besides, with the increase of vanadium loadings, the Lewis acid content increases at first and then decreases, and the content of acid sites in middle strength keeps decreasing. Though the deposited coke on V3+/Al 2 O 3 was just 2.5 wt% during 8.5 h consecutive DH reaction, the valence state of vanadium was still influenced and the fraction of inert V4+ species increased steadily. This study will improve the potential for industrial application of vanadium-based DH catalyst, and offer theoretical guidance for optimization of ideal DH catalysts. [ABSTRACT FROM AUTHOR]

The reversible hydrogenation/dehydrogenation of aromatic molecules, known as liquid organic hydrogen carriers, is considered as an attractive option for the safe storage and release of elemental hydrogen. The recently reported efficient synthetic routes to obtain methoxy-biphenyls in high yield make them promising candidates for hydrogen storage. In this work, a series of methoxy-substituted biphenyls and their structural parent compounds were studied. The absolute vapour pressures were measured using the transpiration method and the enthalpies of vaporisation/sublimation were determined. We applied a step-by-step procedure including structure–property correlations and quantum chemical calculations to evaluate the quality of thermochemical data on the enthalpies of phase transitions and enthalpies of formation of the studied methoxy compounds. The data sets on thermodynamic properties were evaluated and recommended for calculations in chemical engineering. A thermodynamic analysis of chemical reactions based on methoxy-biphenyls in the context of hydrogen storage was carried out and the energetics of these reactions were compared with the energetics of reactions of common LOHCs. The influence of the position of the methoxy groups in the rings on the enthalpies of the reactions relevant for hydrogen storage was discussed. [ABSTRACT FROM AUTHOR]

Herein, cadmium (Cd)-, tellurium (Te)-, selenium (Se)-, and sulfur (S)-doped titanium dioxide (TiO2) support material catalysts are prepared via incipient wetness impregnation. Hydrogen generation performances of the prepared catalysts from sodium borohydride (NaBH4) by methanolysis are investigated. Experimental studies are carried out under ultraviolet (UV) illumination and in the dark. The highest initial hydrogen generation rate is reached on 0.1% Cd/TiO2 catalyst under UV illumination. The optimum catalyst, sodium borohydride, and methanol amounts and temperature parameters affecting the initial hydrogen generation rate are investigated and obtained as 0.025 g, 0.150 g, 2 mL, and 60°C, respectively. The initial hydrogen generation rate of 0.1% Cd/TiO2 catalyst is 16130.64 mL/min.gcat in optimum conditions. The activation energy of the reaction with the 0.1% Cd/TiO2 catalyst is calculated by carrying out kinetic studies. The activation energy is 22.48 kJ/mol. X-ray diffraction (XRD), electron microscopy with energy-dispersive x-ray spectroscopy (SEM-EDX), inductively coupled plasma mass spectrometry (ICP-MS), x-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) analytical techniques are performed to characterize the catalysts. The results show that TiO2 catalysts doped with Cd, Te, Se, and S, which are cheaper than noble metals, are promising for the production of hydrogen from NaBH4 by methanolysis under UV illumination. [ABSTRACT FROM AUTHOR]

Background and objectives: Pulp bleaching is a concern of many conservationists. Research has been conducted with the aim of evaluating some traditional bleaching materials used in the preservation of documents and books, such as hydrogen peroxide and sodium borohydride, which shows that these materials do not significantly improve the mechanical properties of historical papers. Also, investigating the effect of reducing agents on oxidized papers has shown the effectiveness of tert-butylamine borane complex. In another study, five dyeing processes with oxidizers (calcium hypochlorite, hydrogen peroxide in two concentrations, light bleaching and potassium permanganate) and two dyeing processes with reducing agents (sodium borohydride and tert-butylamine borane) were compared. Their effect on alfa cellulose (Whatman filter paper) and two different historical papers have been investigated. The results indicate that all the tested dye removal methods have led to a clear increase. Due to the differences of opinion, in this research, the effectiveness of two reducing agent sodium borohydride and sodium dithionite on the appearance and structural characteristics of paper is investigated. Methodology: In this research, Whatman Filter Paper No. 1 (Whatman Filter Paper No. 1) made in England with a thickness of 180 microns, diameter of 11 cm, basis weight of 87 grams per square meter and ash content of 0.06% was used. . Chemical reagents including potassium persulfate, sodium borohydride and sodium dithionite reagent grade were prepared in a laboratory from Merck, Germany.Three solutions including potassium persulfate (2% by weight/volume), sodium borohydride (1% by weight/volume), sodium dithionite (1% by weight/volume) in distilled water (distilled water, pH; 7), to perform tests on zinc. Paper samples have been used by immersion. Whatman filter paper samples were subjected to oxidation in 2% peta persulfate in distilled water for 2 days (48 hours) and then the samples were immersed. Next, the identified samples were modified by two solutions of sodium borohydride and sodium dithionite 1% in distilled water for 1 to 5 hours and then purified in distilled water. Also, the samples were subjected to accelerated aging according to ASTM standard number D4714-96 at a temperature of 90±2 centigrade and a relative humidity of 50±2% for 384 hours. Test methods include potentiostat, colorimetry, tensile strength, pH measurement, scanning electron microscope and infrared examination. Results: The results show that potassium persulfate is the most neutralizing solution among the three solutions used on the first day, and it also indicates the reducing power of two solutions of sodium dithionite and sodium borohydride, which according to the test results, sodium borohydride is the reducing power compared to sodium dithionite. The sample prepared with pH 3.92, after accelerated aging, was accompanied by an increase of several units of pH after modification with two reducing substances. Examining the data obtained from the tensile strength test shows that in comparison with the tested samples with a tensile index of 1.06, the samples modified with sodium borohydride and sodium dithionite increased the index in all five modified periods. The infrared spectrometry investigation of the samples modified with sodium borohydride and sodium dithione shows that this old material improves the structure of cellulose after aging by changing the C=O bonds to C-O and reducing the area of 1640 cm-1.. The reduction of the absorption band in the region of 1640 cm-1 has been opened in almost all time cases with this material compared to the modified sample. Based on the data, samples modified with sodium borohydride and sodium dithionite had a significant increase (approximately 25 units) in the Lfactor (light-darkness) after aging, indicating that two substances have increased the brightness of the sample by reviving the color compounds. In the microscopic examination of the surface of the fibers, in the samples identified with potassium persulfate, local separation of the fibers is observed. In the samples modified with sodium borohydride and sodium dithionite, fibers with higher consistency and entanglement are observed. Conclusion: Double bonds and carbon groups in paper samples formed with potassium persulfate have been the main responsible for the yellowness and darkness of the paper. The reducing agents, sodium borohydride and sodium dithionite reduce this aldehyde and ketone to hydrocarbon. With the loss of multiple conjugates, the light absorption of the paper is reduced and this causes the paper to brighten. The double bonds and their regeneration also cause rearrangement of the cellulose chain, which has resulted in increasing the mechanical resistance and strength of the paper samples. [ABSTRACT FROM AUTHOR]

A mixture of B(2,6-F SB 2 sb C SB 6 sb H SB 3 sb ) SB 3 sb and the corresponding tetrabutylammonium borohydride salt effectively isomerizes iminium ion B 38 b to form iminium B 41 b via a sequence of hydride donation to form B 39 b followed by hydride abstraction. The ammonium borohydride then eliminates H SB 2 sb to reform the active B(C SB 6 sb F SB 5 sb ) SB 3 sb catalyst and amine B 72 b . Interestingly, the Lewis acid B(2,6-F SB 2 sb C SB 6 sb H SB 3 sb ) SB 3 sb is significantly less electron-deficient than B(C SB 6 sb F SB 5 sb ) SB 3 sb , which is almost exclusively used in organoborane-mediated hydride abstraction with amines. Keywords: boron; hydride abstraction; amines; iminium; functionalization EN boron hydride abstraction amines iminium functionalization 2117 2128 12 10/31/23 20231127 NES 231127 Graph 1 Introduction Organoboranes are widely used as reagents and building blocks in synthetic chemistry. [Extracted from the article]

A method has been described for accessing α‐seleno alkyl boronates. The selenoboration was achieved via the diboration of carbonyl compounds to give α‐oxyl boronates, which then undergo 1,2‐metalate rearrangement in the presence of lithium selenolates and trifluoroacetic anhydride (TFAA). A variety of structurally diverse substrates were compatible with this protocol and efficiently provides difunctionalized products from simple starting materials. The presence of the boronic ester in the resulting organoselenium compounds serves as a versatile synthetic handle for various functionalizations. Mechanistic studies revealed that the binding of selenium nucleophile to both the boron centers in α‐oxyl boronate esters. [ABSTRACT FROM AUTHOR]

The interaction between protic hydrogen (H+) and hydridic hydrogen (H−) species gives rise to H2 and spawns the establishment of metal‐N−H hydrogen storage material systems. N‐based compounds such as metal amides (M−NH2) have shown viability for protic H generation. In this preliminary research, we adopted a chemical reaction approach using a hydrogen‐enriched quasi‐aromatic tri‐amide "melamine (C3H6N6)" as protic H feedstock and lithium hydride (LiH) as the hydridic H‐based destabilizer aiming at expanding metal and organic substrates and developing new metalorganic hydride materials. The dehydrogenation kinetics and reaction pathways of C3H6N6−xLiH (x=1, 3 or 6) composites on heating and ball‐milling conditions were investigated in detail. The results showed that C3H6N6−LiH consisting of a 1/6 mole ratio can evolve 6.6 wt % H2 (approximately 5.75 equiv. H2) at room temperature through mechanochemical method of ball‐milling. Interestingly, it showed different reaction paths under heating, C3H6N6−6LiH composite could release 2.87 wt % hydrogen under 210 °C and transform into a CN heterocyclic intermediate structure examined by NMR, FTIR, XRD, and Raman characterizations. [ABSTRACT FROM AUTHOR]

Magnéli phase titanium oxides, also called titanium sub-oxides (TinO2n−1, 4 < n < 9), are a series of electrically conducting ceramic materials. The synthesis and applications of these materials have recently attracted tremendous attention because of their applications in a number of existing and emerging areas. Titanium sub-oxides are generally synthesized through the reduction of titanium dioxide using hydrogen, carbon, metals or metal hydrides as reduction agents. More recently, the synthesis of nanostructured titanium sub-oxides has been making progress through optimizing thermal reduction processes or using new titanium-containing precursors. Titanium sub-oxides have attractive properties such as electrical conductivity, corrosion resistance and optical properties. Titanium sub-oxides have played important roles in a number of areas such as conducting materials, fuel cells and organic degradation. Titanium sub-oxides also show promising applications in batteries, solar energy, coatings and electronic and optoelectronic devices. Titanium sub-oxides are expected to become more important materials in the future. In this review, the recent progress in the synthesis methods and applications of titanium sub-oxides in the existing and emerging areas are reviewed. [ABSTRACT FROM AUTHOR]

LiBH4 has been considered as one of the most promising energy storage materials with its ultrahigh hydrogen capacity, which can supply hydrogen through hydrolysis process or realize hydrogen-to-electricity conversion via anodic oxidation reaction of direct borohydride fuel cells (DBFCs). However, the realization of practical hydrogen applications heavily depends on the effective synthesis of high-purity LiBH4 and recycling of the spent fuels (LiBO2·xH2O). The present work demonstrates a convenient and high-efficiency solvent-free strategy for regenerating LiBH4 with a maximum yield close to 80%, by retrieving its by-products with MgH2 as a reducing agent under ambient conditions. Besides, the hydrogen released from the regeneration course can completely compensate the demand for consumed MgH2. The isotopic tracer method reveals that the hydrogen stored in LiBH4 comes from both MgH2 and coordinated water bound to LiBO2. Here, the expensive MgH2 can be substituted with the readily available and cost-effective MgH2−Mg mixtures to simplify the regeneration route. Notably, LiBH4 catalyzed by CoCl2 can stably supply hydrogen to proton exchange membrane fuel cell (PEMFC), thus powering a portable prototype vehicle. By combining hydrogen storage, production and utilization in a closed cycle, this work offers new insights into deploying boron-based hydrides for energy applications.

Micro‐sized silicon (mSi) anodes offer advantages in cost and tap density over nanosized counterparts. However, its practical application still suffers from poor cyclability and low initial and later‐cycle coulombic efficiency (CE), caused by the unstable solid electrolyte interphase (SEI) and irreversible lithiation of the surface oxide layer. Herein, a bifunctional fluorine (F)‐free electrolyte was designed for the mSi anode to stabilize the interphase and improve the CE. A combined analysis revealed that this electrolyte can chemically pre‐lithiate the native oxide layer by the reductive LiBH4, and relieve SEI formation and accumulation to preserve the internal conductive network. The significance of this F‐free electrolyte brings unprecedented F‐free interphase that also enables the high‐performance mSi electrode (80 wt % mSi), including high specific capacity of 2900 mAh/g, high initial CE of 94.7 % and excellent cyclability capacity retention of 94.3 % after 100 cycles at 0.2 C. This work confirms the feasibility of F‐free interphase, thus opening up a new avenue toward cost‐advantaged and environmentally friendly electrolytes for more emerging battery systems. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) synthesised by modified Tour's method was decorated with copper and zinc nanoparticles (NPs) and simultaneously reduced by sodium borohydride to obtain a nanocomposite of reduced GO with copper and zinc NPs (rGO–Cu–Zn). The nanocomposite rGO–Cu–Zn was characterised by transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The rGO–Cu–Zn was tested against Xanthomonas euvesicatoria (X. euvesicatoria), which attacks tomatoes and causes bacterial spots (BSs), and compared with the commercial product Champion 50 WG. Total bacterial growth inhibition was observed for the 1% rGO–Cu–Zn, whereas Champion 50 WG at the same concentration inhibited but did not eradicate all the bacterial colonies. To evaluate the negative effect of the rGO–Cu–Zn on the molecular level, the expression of the genes associated with the action of abiotic and biotic stress factors was analysed. Gene expression in the plants treated with 10% rGO–Cu–Zn did not exhibit a noticeable increase. [ABSTRACT FROM AUTHOR]

In this contribution, we propose the couple 1-Cyclohexylethanol/Acetophenone as a new biobased and bifunctional LOHC. This material shows promises for hydrogen storage by DFT modelling, while commercial catalysts were identified to carry out both hydrogenation and dehydrogenation: Ru/Al 2 O 3 was found to catalyse the complete hydrogenation of the LOHC at 115 °C in 2 h with 98% selectivity and, for the first time, Pt/C carries out the dehydrogenation at 205 °C in 36 h with total conversion but with a limited Degree of Dehydrogenation of 72%. The system was cycled three times during which up to 50% of the total hydrogen capacity was exploited, stable after 3 cycles. Kinetics experiments and DFT modelling of the reactions intermediates show that a system pairing C–O and C–C bonds is prone to degradation, due to side-reactions initiated by the O-moiety and the reversible hydrogenation of the C O bond during the dehydrogenation step. [Display omitted] • 1-Cyclohexylethanol/Acetophenone was proposed as a new biobased bifunctional LOHC. • Full hydrogenation and dehydrogenation were achieved with heterogeneous catalysts. • Energies of activation of each function was measured during the dehydrogenation. • Up to 53% of the total hydrogen capacity was exploited during the cycling. • DFT modelling rationalized the dehydrogenation pathway and degradation products. [ABSTRACT FROM AUTHOR]