Hydro-catalytic treatment of organoamine boranes for efficient thermal dehydrogenation for hydrogen production

This study aims to present the hydro-catalytic treatment of organoamine boranes for efficient thermal dehydrogenation for hydrogen production. Organoamine boranes, methylamine borane (MeAB), and ethane 1,2 diamine borane (EDAB), known as ammonia borane (AB) carbon derivatives, are synthesized to be used as a solid-state hydrogen storage medium. Thermal dehydrogenation of MeAB and EDAB is performed at 80 °C, 100 °C, and 120 °C under different conditions (self, catalytic, and hydro-catalytic) for hydrogen production and compared with AB. For this purpose, a cobalt-doped activated carbon (Co-AC) catalyst is fabricated. The physicochemical properties of Co-AC catalyst is investigated by well-known techniques such as ATR/FT-IR, XRD, XPS, ICP-MS, BET, and TEM. The synthesized Co-AC catalyst obtained in nano CoOOH structure (20 nm, 12% Co wt) is formed and well-dispersed on the activated carbon support. It has indicated that Co-AC exhibits efficient catalytic activity towards organoamine boranes thermal dehydrogenation. Hydrogen release tests show that hydro-catalytic treatment improves the thermal dehydrogenation kinetics of neat MeAB, EDAB, and AB. Co-AC catalyzed hydro-treatment for thermal dehydrogenation of MeAB and EDAB acceleras the hydrogen release from 0.13 mL H₂/min to 46.12 mL H₂/min, from 0.16 mL H₂/min to 38.06 mL H₂/min, respectively at 80 °C. Moreover, hydro-catalytic treatment significantly lowers the H₂ release barrier of organoamine boranes thermal dehydrogenation, from 110 kJ/mol to 19 kJ/mol for MeAB and 130 kJ/mol to 21 kJ/mol for EDAB. In conclusion, hydro and catalytic treatment presents remarkable synergistic effect in thermal dehydrogenation and improves the hydrogen release kinetics.     

Non-linear kinetic analysis of catalytic hydrolysis of ethylenediamine bisborane with nano-structured Pd/TiO2 catalyst

In this study, the hydrogen generation from catalytic hydrolysis of ethylenediamine bisborane (EDAB) solution catalyzed by nanostructured titanium dioxide (TiO₂) supported Pd metallic catalyst was carried out. TiO₂ support material was synthesized by the sol-gel method from titanium (IV) ethoxide. Pd was loaded into TiO₂ by the conventional impregnation-reduction method and reduction was carried out at 750 °C in an H₂ atmosphere. The characterization of catalysts was done with SEM-EDX and multi-point BET analysis. To investigate the hydrogen production by catalytic hydrolysis of EDAB, parameters such as Pd loading (2–4% by weight) and temperature (40–80 °C) were chosen in the presence of ethylenediamine bisborane aqueous solution (0.034% by weight). Detailed non-linear kinetic analysis was applied to the experimental data by considering and Langmuir-Hinshelwood model and power law. The activation energy E_a was calculated as E_a = 33.61 kJ mol^?1 and E_a = 36.32 kJ mol^?1 according to Langmuir-Hinshelwood and power-law model respectively for the Pd/TiO₂ catalyst.     

Hydrogen production via copper nanocatalysts stabilized by cyclen derivative hydrogel networks from the hydrolysis of ammonia borane and ethylenediamine bisborane

In this study, p(AAm-co-TACYC) hydrogels were synthesized using TACYC crosslinker. The p(AAm-co-TACYC) hydrogel was used for preparation of Cu(0) nanoparticles as support material. The p(AAm-co-TACYC)@Cu was prepared by chemical reduction of Cu²⁺ ions in the p(AAm-co-TACYC) networks and was structurally characterized in detail. Later the catalytic activity of p(AAm-co-TACYC)@Cu was investigated for hydrogen production from AB and EDAB hydrolysis. Detailed kinetic studies were performed for both hydrogen storage materials. The p(AAm-co-TACYC)@Cu was a more active catalyst for the EDAB hydrolysis reaction. The E_a values of p(AAm-co-TACYC)@Cu for the AB and EDAB hydrolysis reactions were determined as 68.36 kJ mol⁻¹ and 39.07 kJ mol⁻¹, respectively. In addition to the perfect catalytic activity of p(AAm-co-TACYC)@Cu, it had good reusability. After ten consecutive uses for AB and EDAB hydrolysis, the p(AAm-co-TACYC)@Cu still had 88% and 85% of initial activity, respectively.     

Hydrogen production from sodium borohydride originated compounds: Fabrication of electrospun nano-crystalline Co3O4 catalyst and its activity

Electrospun nanofibers are prepared through electrospinning followed by post-treatment and preferred to use in catalytic applications. The electrospinning provides advantages for active catalysts design based on activity profiles and features of catalyst. In the present study, we fabricated nano-crystalline cobalt oxide (Co₃O₄) catalyst by electrospinning technique followed by thermal conditioning. Polyacrylonitrile (PAN) based Co as-spun mats (Co/NMs) with homogeneous diameter were prepared by electrospinnig process under several conditions as applied voltage (15–25 kV), working distance (5–7.5 cm) with the feed rate of 1 ml min⁻¹. The calcination process as a post-treatment was applied at different temperatures (232 °C, 289 °C and 450 °C) to obtain electrospun nano-crystalline Co₃O₄ catalyst. Co/NMs catalysts were characterized by XRD, SEM, TEM, XPS, FT-IR, TG/DTG, and ICP-MS techniques. The parametrically study was performed for evaluating the hydrogen production activity of catalyst from sodium borohydride (NaBH₄, SBH) and its originated compounds as ammonia borane (NH₃BH₃, AB) and methyl-amine borane (CH₃NH₂BH₃, MeAB). The relation between the internal-external properties and catalytic activities of catalysts for hydrogen production was investigated. The beadless Co/NMs-1 catalyst with homogeneous diameter was obtained under electrospinnig process conditions at 15 kV applied voltage and 7.5 cm working distance. All catalysts showed activity for hydrogen production, also the significant effect of post treatment process was observed on the catalytic activity as given order: Co/NMs-1₄₅₀ > Co/NMs-1₂₈₉ > Co/NMs-1 > Co/NMs-1₂₃₂. Furthermore, mesoporous Co₃O₄ cubic crystals (26 nm) in fibrous architecture was prepared by 450 °C-post-treatment. Hydrogen production rates were recorded at 60 °C as 2.08, 2.20, and 6.39 l H₂.g_cat⁻¹min⁻¹ for NaBH₄, CH₃NH₂BH₃, and NH₃BH₃, respectively.     

TiO2–CdS supported CuNi nanoparticles as a highly efficient catalyst for hydrolysis of ammonia borane under visible-light irradiation

TiO₂–CdS nanotubes (NTs) were used for the first time as a support to load metal nanoparticles (NPs) for the hydrolysis of ammonia borane (AB) which is a new strategy. The TiO₂–CdS NTs support was first synthesized using a hydrothermal method, and then the CuNi NPs were loaded using a liquid-phase reduction method. The synthesized samples were characterized by XRD, SEM-EDS, TEM, XPS, ICP, UV–Vis, and PL analyses. The characterization results show that the CuNi NPs existed in the form of an alloy with a size of ~1.2 nm and uniformly dispersed on the support. Compared with their single metal counterparts, the bimetallic CuNi-supported catalysts showed a higher catalytic activity in the hydrolysis of AB under visible-light irradiation: Cu_0·45Ni_0·55/TiO₂–CdS catalyst had the fastest hydrogen evolution rate with a high conversion frequency (TOF) of 25.9 mol_H2·mol_cat⁻¹ min⁻¹ at 25 °C and low activation energy of 32.8 kJ mol⁻¹. Cu_0.45Ni_0.55/TiO₂–CdS catalyst showed good recycle performance, maintaining 99.3% and 85.6% of the original hydrogen evolution rate even after five and ten recycles, respectively. Strong absorption of visible light, improved electron–hole separation efficiency, and metal synergy between Cu and Ni elements played a crucial role in improving the catalytic hydrolysis performance of AB. The catalyst prepared in this study provides a new strategy for the application of photocatalysts.     

Strategic synthesis of graphene supported trimetallic Ag-based core–shell nanoparticles toward hydrolytic dehydrogenation of amine boranes

We reported the synthesis and characterization of two trimetallic (Ag@CoFe, and Ag@NiFe) core–shell nanoparticles (NPs), and their catalytic activity toward hydrolytic dehydrogenation of ammonia borane (AB) and methylamine borane (MeAB). The as-synthesized trimetallic core–shell NPs were obtained via a facile one-step in situ procedure using methylamine borane as a reducing agent and graphene as the support under ambient condition. The as-synthesized NPs are well dispersed on graphene, and exhibit higher catalytic activity than the catalysts with other conventional supports, such as the SiO₂, carbon black, and γ-Al₂O₃. Additionally, compared with NaBH₄ and AB, the as-synthesized Ag@CoFe/graphene NPs reduced by MeAB exhibit the highest catalytic activity, with the turnover frequency (TOF) value of 82.9 (mol H₂ min⁻¹ (mol Ag)⁻¹), and the activation energy (E_a) value of 32.79 kJ/mol. Furthermore, the as-prepared NPs exert good durable and magnetically recyclability for the hydrolytic dehydrogenation of AB and MeAB. Moreover, this simple strategic synthesis method can be easily extended to the facile preparation of other graphene supported multi-metal core–shell NPs.     

CuO–Ru0.3@Co3O4 nanocomposites act as a tandem catalyst for dehydrogenation of ammonia borane and hydrogenation of nitrobenezene

The development of catalysts with high activity for tandem reaction are all the ways pursued by chemists. Herein, CuO–Ru_0.3@Co₃O₄ has been synthesized and used as efficient tandem catalyst to promote the release of hydrogen from hydrolytic dehydrogenation of ammonia borane (AB) to catalyze the hydrogenation of nitrobenezenes (NBs). The catalyst exhibits the TOF of 29.87 min^?1 and provides the apparent activation energy of 45.2 kJ mol^?1 for the hydrolytic dehydrogenation of AB. Additionally, benefited from the magnetic separation capability, up to 99% of its initial catalytic activity is retained after four catalytic cycles.     

One-pot co-reduction synthesis of orange-like Pd@Co@P nanoparticles supported on rGO for catalytic hydrolysis of ammonia borane

Transition metal phosphide based orange-like Pd@Co@P nanoparticles supported on reduced graphene oxide (Pd@Co@P/rGO) have been synthesized by a one-pot co-reduction at room temperature using methylamine borane (MeAB) as the reducing agent. The prepared Pd@Co@P/rGO nanoparticles were characterized by powder X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), selected area electron diffraction (SAED) and confocal Raman microscopy (Raman). Compared with Pd/rGO and Pd@Co/rGO, the Pd@Co@P/rGO catalyst has higher catalytic activity for the hydrolytic production of ammonia borane (AB) with the turnover frequency value (TOF) of 127.57 min⁻¹ and the activation energy of 39.05 kJ mol⁻¹. This excellent catalytic performance may be caused by the orange-like structure and good dispersion of Pd@Co@P/rGO nanoparticles, and the synergistic electron interactions between palladium, cobalt, and phosphorus.     

In situ facile synthesis of bimetallic CoNi catalyst supported on graphene for hydrolytic dehydrogenation of amine borane

Well dispersed magnetically recyclable bimetallic Co_xNi_1−x (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9, 1) nanoparticles (NPs) supported on graphene have been synthesized via a facile in situ one-step procedure, using the mixture of sodium borohydride (NaBH₄) and methylamine borane (MeAB) as the reducing agent under ambient condition. These NPs were composition dependent for catalytic hydrolysis of amine boranes. Among all the CoNi/graphene catalysts tested, the Co_0.9Ni_0.1/graphene NPs exhibit the highest catalytic activity toward hydrolysis of AB with the turnover frequency (TOF) value of 16.4 (mol H₂ min⁻¹ (mol catalyst)⁻¹), being higher than that of most reported non-noble metal-based NPs, and even many noble metal-based NPs. Moreover, the activation energy (E_a) value is 13.49 kJ/mol, which is the second lowest value ever reported for catalytic hydrolytic dehydrogenation of ammonia borane, indicating the superior catalytic performance of the as-synthesized Co_0.9Ni_0.1/graphene catalysts. Additionally, Compared with other reducing agents, such as NaBH₄, AB, MeAB, and the mixture of NaBH₄ and AB, the as-synthesized Co_0.9Ni_0.1/graphene catalysts reduced by the mixture of NaBH₄ and MeAB exert the highest catalytic activity. The Co_0.9Ni_0.1 NPs supported on graphene exhibit higher catalytic activity than catalysts with other conventional supports, such as SiO₂, carbon black, and γ-Al₂O₃. Furthermore, the as-synthesized Co_0.9Ni_0.1/graphene NPs show good recyclability and magnetically reusability for the hydrolytic dehydrogenation of amine boranes, which make the practical reusing application of the catalysts more convenient.     

Improved catalytic performance of metal oxide catalysts fabricated with electrospinning in ammonia borane methanolysis for hydrogen production

Electrospun Ni and Cu metal oxide catalysts are successfully synthesized through electrospinning and conventional sol-gel methods to show advantages of electrospinning on catalytic performance in ammonia borane (NH₃BH₃) methanolysis for hydrogen production. An experimental assessment is presented by the characterization of interior and exterior properties of all catalysts and their catalytic activity towards NH₃BH₃ methanolysis. The systematic studies are performed in order to figure out of kinetic interpretation. Catalytic NH₃BH₃ methanolysis reactions are carried out at different catalyst amounts (5–15 mg), initial NH₃BH₃ concentrations (0.36–6.0 M) and temperatures (20–50 °C). Thanks to the higher pore volume/S_BET ratio, fiber type nanostructured Cu oxide catalyst exhibits the highest catalytic activity compared with sol-gel prepared ones. The results of kinetic studies show that the fiber type Cu oxide catalyst catalyzed methanolysis of NH₃BH₃ and follows the first order reaction kinetic model with 35 kJ mol⁻¹ activation energy value.     

Hydrogen production from ammonia borane via hydrogel template synthesized Cu, Ni, Co composites

In situ Co, Cu and Ni nanoparticles were synthesized by chemical reduction of the absorbed Co (II), Cu (II) and Ni (II) ions inside hydrogel networks prepared from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) and were used as a catalyst system in the generation of hydrogen in hydrolysis of ammonia borane (AB). Several parameters affecting the hydrolysis reaction such as the type of the metal, the amount of catalyst, the initial concentration of AB, and temperature, were investigated. The activation energy values in the hydrolysis reaction of AB solution in the presence p(AMPS)-Co, p(AMPS)-Cu and p(AMPS)-Ni catalyst systems were calculated as E_a = 47.7 kJ mol⁻¹, 48.8 kJ mol⁻¹ and 52.8 kJ mol⁻¹, respectively. Thus, the catalytic activity of the metal nanoparticles prepared inside the same hydrogel matrix was found to be Ni < Cu < Co.     

Ionic liquid-based deep eutectic solvents as novel solvent-cum-catalyst media for thermal dehydrogenation of chemical hydrides

The current work explores the usage of novel synthesized Deep Eutectic Solvent (DES) as a catalyst cum solvent media for the thermal dehydrogenation of chemical hydrides, namely Ammonia Borane (AB) and Ethylene diamine bisborane (EDAB). In the first instance, the quantum chemistry based COSMO-SAC (COnductor like Screening MOdel Segment Activity Coefficient) model was used for the selection of the pertinent solvent. 1-Butyl-3-methylimidazolium methanesulfonate: Imidazole ([BMIM][MeSO₃]:[Im]) turned out to be an ideal eutectic mixture with the highest predicted solubility with amine boranes. The DES was synthesized by combining the Hydrogen Bond Acceptor (HBA), namely 1-Butyl-3-methylimidazolium methanesulfonate and Imidazole as Hydrogen Bond Donor (HBD) at a molar ratio of 1:2 and T = 70 °C. The formation of DES was confirmed by recording the NMR spectra. Further, the thermal dehydrogenation study was performed at a vacuum of 4 × 10^?2 mbar (gauge pressure) of AB/DES and EDAB/DES systems at 105 °C, where a hydrogen equivalent of 1.40 and 2.55 was produced, respectively. The residual samples were further analyzed through ¹H NMR analysis for the reaction mechanism and to confirm the role of Ionic Liquid-based DES as catalyst cum solvent media.     

Ag(0) nanocatalyst stabilized with networks of p(SPA-co-AMPS) for the hydrogen generation process from ethylenediamine bisborane hydrolysis

In this study, the hydrogen generation from the catalytic hydrolysis of the ethylenediamine bisborane (EDAB) was performed. For this purpose, the p(sulfopropyl acrylate potassium salt-co-2-acrylamido-2-methylpropansulfonic acid sodium salt)@Ag(0) (p(SPA-co-AMPS)@Ag) catalyst was prepared. Later the p(SPA-co-AMPS)@Ag containing Ag(0) particles with nanodimensions was used as catalyst in EDAB hydrolysis. Our study is the first in the literature from this aspect, and investigated in detail the effect of catalyst amount, reactive concentration, temperature and dry or swollen nature of the catalyst on the EDAB hydrolysis. At the end of the reaction series, the hydrolysis reaction of EDAB with p(SPA-co-AMPS)@Ag catalyst was determined to have activation energy (E_a) of 43.24 kJmol^-1. Additionally, the turn over frequency (TOF) was 0.560 mol H₂(mol Ag(0).min)⁻¹ at 30 °C. The p(SPA-co-AMPS)@Ag catalyst had perfect reusability with 95% of initial activity after the 5th use for the hydrogen generation from EDAB.     

Carbon-supported Ni3B nanoparticles as catalysts for hydrogen generation from hydrolysis of ammonia borane

We report the preparation of Ni₃B and carbon-supported Ni₃B (denoted as Ni₃B/C) nanoparticles, and their catalytic performance for hydrogen generation from hydrolytic dehydrogenation of ammonia borane (NH₃BH₃, AB). Ni₃B and Ni₃B/C were prepared via a chemical reduction and crystallization in tetraethylene glycol solution. The obtained Ni₃B catalysts are in well-defined crystalline state and Ni₃B/C catalysts have a high dispersion in the carbon. The hydrogen generation measurement shows that the carbon-supported Ni₃B presents enhanced catalyst activity during hydrolytic dehydrogenation of AB. Among the as-prepared Ni₃B/C catalysts, Ni₃B/C with 34.25 wt% Ni₃B loading displays the best catalytic activity, delivering a high hydrogen release rate of 1168 mL min⁻¹ g⁻¹ and the lower activation energy of 46.27 kJ mol⁻¹. The kinetic results show that the hydrolysis is a first-order reaction in catalyst concentration, while it is a zero-order in AB concentration. Furthermore, the Ni₃B/C is a recyclable catalyst under mild reaction conditions, indicating that the carbon-supported Ni₃B is a promising catalyst for AB hydrolytic dehydrogenation.     

Nanosizing ammonia borane with nickel – An all-solid and all-in-one approach for H2 generation by hydrolysis

Ammonia borane NH₃BH₃ (AB) and nickel (Ni) have been considered together as an all-solid and all-in-one material for H₂ generation by hydrolysis at 20–50 °C. Our novel approach, denoted Ni/AB, consists of AB nanoparticles within a Ni matrix. Upon contact with water, Ni/AB readily hydrolyzes and liberates H₂ with a turnover frequency of 13.8 mol(H₂) mol_Ni^?1 min^?1 at 43.3 °C. The apparent activation energy, determined over the temperature range 23.5–50.4 °C, is low, with 19.5 ± 4.1 kJ mol^?1. These results imply that such a Ni matrix embedding AB acts as an effective catalyst. Beyond the catalytic performance, this is the first report of the successful utilization of an all-solid and all-in-one approach for the hydrolysis of AB, and the work brings unique perspectives for one-shot catalytic systems.     

Ni–B and Zr–Ni–B in-situ catalytic performance for hydrogen generation from sodium borohydride,ammonia borane and their mixtures

In this study, the parameters on the catalytic hydrolysis of the sodium borohydride (NaBH4, SBH) and ammonia boranes (NH3BH3, AB) mixtures were investigated such as the effect of Zr additive in the catalyst, using in-situ or powder catalysts, the molar ratio of the SBH/AB mixture (2, 4, 8, neat SBH, neat AB) and temperature. As the catalyst, in-situ synthesized Ni–B and Zr–Ni–B for the first time were used to produce H₂ from hydrolysis of the SBH and AB mixtures. The SBH and AB mixtures were used to determine provided or not an effect on reaction. Catalyst preparation and hydrolysis reactions took place in the same reactor spontaneously for in-situ works. The Zr–Ni–B catalyst gives better results than Ni–B and increases efficiency at 25 °C and 35 °C temperature. When Zr–Ni–B catalyst compared experimentally among themselves, the best yield result at 45 °C temperature, for neat SBH, mole ratio in 4 and mole ratio in 8, as 87%, 86% and 83% respectively. For hydrolysis reactions with Zr–Ni–B catalyst, activation energies of SBH and AB were calculated as 45.23 kJ/mol and 79.76 kJ/mol, respectively. SEM, BET, XPS analyzes have been used to characterize these catalysts. The addition of Zr provided increase effect on the surface area. The surface area increases from 44.33 m²/g to 175.50 m²/g.     

Enhanced catalytic performance of CuNi bimetallic nanoparticles for hydrogen evolution from ammonia borane hydrolysis

Ammonia borane (AB, NH₃BH₃) hydrolysis is an effective way to safely generate hydrogen. However, a suitable catalyst is indispensable because the hydrolytic reaction cannot take place kinetically at room temperature. In this work, CuNi alloy nanoparticles are immobilized on porous graphitic carbon nitride (g-C₃N₄) with a facile adsorption-chemical reduction method. Benefiting from the hierarchical porous structure of the support, the interesting alloy effect of Cu and Ni, as well as the synergistic effect between g-C₃N₄ and the CuNi alloys, the optimal Cu_0·7Ni_0.3/g-C₃N₄ catalyst displays excellent catalytic performance in AB hydrolysis, such as high turnover frequency (2.08 min⁻¹, at 303 K), low apparent activation energy (23.58 kJ mol⁻¹), and satisfactory durability. The results verify that the optimal catalyst has particular potential in hydrogen energy utilization due to the advantages such as the facile preparation procedure, low cost and excellent catalytic behavior.     

Mo-doped Ni-based catalyst for remarkably enhancing catalytic hydrogen evolution of hydrogen-storage materials

Ni-based alloys are considered as the efficient catalyst for hydrogen-storage materials decomposition. Herein, we applied an in-situ melt-quenching method to dope Mo in Ni-based alloy for catalytic hydrogen evolution from hydrogen-storage materials. Importantly, Mo doped Ni-based catalyst exhibits more than 6 times higher TOF value than that of pure Ni both in AB hydrolysis and hydrazine decomposition, because Mo acts as an electron donor to improve the reducibility of Ni. Hydrogen evolution kinetics were studied over a range of temperatures (303–353 K) and initial feed concentrations (catalyst/hydrogen-storage materials (wt/wt) ratios = 0.2–10). Under optimal reaction conditions, the H₂ evolution rate reaches 1.92 mol H₂/(mol_cat min) and 0.05 mol H₂/(mol_cat min) in the hydrolysis of ammonia borane and decomposition of hydrazine, which are 6.42 and 6.44 times higher than undoped Ni catalyst, respectively. And the apparent activation energy of ammonia borane hydrolysis and hydrazine decomposition were evaluated to be 26.66 ± 3.31 kJ/mol and 40.01 ± 3.38 kJ/mol, respectively.     

Visible-light-enhanced catalytic hydrolysis of ammonia borane using RuP2 quantum dots supported by graphitic carbon nitride

Hydrolytic dehydrogenation of ammonia borane (AB) driven by efficient catalysts has attracted considerable attention and is regarded as a promising strategy for hydrogen generation. Herein, RuP₂ quantum dots supported on graphitic carbon nitride (g-C₃N₄) were successfully prepared by in-situ phosphorization, yielding a highly efficient photocatalyst toward AB hydrolysis. The catalysts were characterized by field-emission scanning electron microscopy, transmission electron microscopy, x-ray diffraction, x-ray photoelectron microscopy, inductively coupled plasma atomic emission spectroscopy, UV–visible diffuse reflectance spectroscopy and photoluminescence spectroscopy. A conventional water-displacement method was employed to record the hydrogen volume as a function of reaction time. Owing to visible-light irradiation, the initial turnover frequency of the AB hydrolysis was significantly enhanced by 110% (i.e., 134 min^?1) at room temperature. Furthermore, the apparent activation energy decreased from 67.7 ± 0.9 to 47.6 ± 1.0 kJ mol^?1. The photocatalytic hydrolysis mechanism and catalyst reusability were also investigated.     

Decreasing the thermal dehydrogenation temperature of methylamine borane (MeAB) by mixing with poly(methyl acrylate) (PMA)

This paper reports on a hydrogen storage material of poly(methyl acrylate) and methylamine borane (PMA/MeAB) composite, which is synthesized by a simple solution-blending process at room temperature. The thermal decomposition process of the as-prepared composite is investigated by temperature programmed desorption/mass spectrometer (TPD/MS), thermogravimetry (TG) measurements and water displacement method. It is found that PMA/MeAB100 (100 mg PMA with 100 mg MeAB) starts to release H₂ at the temperature of 90.5 °C with the dehydrogenation peak centered at 120.7 °C. This is about 20 °C lower than that of neat MeAB. Meanwhile, the evaporation of MeAB and the volatile byproducts from the dehydrogenation stage of PMA/MeAB100 are also suppressed. The present result shows that the dehydrogenation property of MeAB is enhanced by using PMA/MeAB composite.