Dehydrogenation Kinetics Research Articles

Dehydrogenation kinetics of MgH2-based hydrogen storage tank at different operating temperatures and mass flow rates

The most efficient electrical production from fuel cells integrated with hydride-based hydrogen storage tanks is obtained from suitable dehydrogenation kinetics, facilitating constant flow rate of hydrogen supply for a long period of time. Dehydrogenation kinetics of hydride-based tanks depends strongly on operating temperatures and system pressures, relating to hydrogen mass flow rate (H2-FR) released from the tank. Since a cylindrical tank (96.2 mL) mounted with central heat exchanger containing TiF4-MWCNT-MgH2 (∼45 g) shows excellent de/rehydrogenation and reversibility (5.4 wt % H2 upon 20 cycles), the effects of different operating conditions (T = 300–340 °C and H2-FR = 0.6–1.0 standard L/min) on kinetic properties of this MgH2-based tank are of significant interest. Kinetic properties either rapid or steady-state desorption can be optimized by tuning the operating temperature and H2-FR simultaneously. Moreover, the performances in the axial and radial directions of the tank as well as kinetic behaviors and rate-limiting step during dehydrogenation at different temperatures and H2-FR of MgH2-based tank are investigated.

Remarkable catalytic effect of Ni and ZrO2 nanoparticles on the hydrogen sorption properties of MgH2

In the present study, the catalytic effect of Ni and ZrO2 nanoparticles on the hydrogen absorption and desorption properties of MgH2 has been investigated. The MgH2 nanocomposites were prepared by high-energy ball-milling. The morphology, phase structure, thermal behavior, and hydrogen storage properties of the materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), temperature-programmed desorption (TPD), differential scanning calorimetry (DSC), and the pressure-composition temperature (PCT) methods. ZrO2 and Ni nanoparticles were homogenously dispersed into the MgH2 matrix. The calculated apparent activation energy for dehydrogenation was 63.4 kJ/mol, which was decreased by 80.1 kJ/mol compared to that of as-milled MgH2. As a result, MgH2+5 wt.%Ni+5 wt.%ZrO2 demonstrated improved dehydrogenation and hydrogenation kinetics at 310 °C. The MgH2+5 wt.%Ni+5 wt.%ZrO2 sample released about 6.83 wt.% and absorbed about 6.10 wt.% in less than 30 min. Therefore, the co-catalysis of Ni and ZrO2 significantly enhances the hydrogenation and dehydrogenation properties of MgH2.

Enhanced hydrogen desorption kinetics and cycle durability of amorphous TiMgVNi3-doped MgH2

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.

Mn nanoparticles enhanced dehydrogenation and hydrogenation kinetics of MgH2 for hydrogen storage

Mn nanoparticles (nano-Mn) were successfully synthesized and doped into MgH2 to improve its de/hydrogenation properties. Compared with MgH2, the onset desorption temperature of 10 wt.% nano-Mn modified MgH2 was decreased to 175 °C and 6.7, 6.5 and 6.1 wt.% hydrogen could be released within 5, 10 and 25 min at 300, 275 and 250 °C, respectively. Besides, the composite started to take up hydrogen at room temperature and absorbed 2.0 wt.% hydrogen within 30 min at low temperature of 50 °C. The hydrogenation activation energy of MgH2 was reduced from (72.5±2.7) to (18.8±0.2) kJ/mol after doping with 10 wt.% nano-Mn. In addition, the MgH2 + 10 wt.% nano-Mn composite exhibited superior cyclic property, maintaining 92% initial capacity after 20 cycles.

Theoretical Insights into Dual-Metal-Site Catalysts for the Nonoxidative Coupling of Methane

Direct conversion of methane to C2 hydrocarbons under nonoxidative conditions is an attractive technology but is challenging due to high reaction temperature, severe coke deposition, and low selectivity. Here, we report three dual-metal-site catalysts (DMSCs) based on nitrogen-doped graphene (FeCo–N–C, Fe2–N–C, and Co2–N–C) for nonoxidative coupling of methane to C2 hydrocarbons from a theoretical perspective. Our calculated results reveal that DMSCs present universally better performance in methane activation than single-metal-site catalysts (Fe–N–C and Co–N–C). Among the three DMSCs, Co2–N–C exhibits the best catalytic activity and superior selectivity to ethane in the whole reaction pathway. Our microkinetic modeling reveals that the Co2–N–C catalyst can convert methane to CH3, C2H6, and H2 at 1200 K. The electronic structure analysis and ab initio molecular dynamics simulations demonstrate that Co2–N–C possesses both intrinsic stability and high-temperature stability. Moreover, Co2–N–C also manifests better coke resistance compared with larger Co clusters, indicated by the difficult kinetics of methane deep dehydrogenation to naked carbon. This work provides a potential catalyst prototype for the selective conversion of methane to C2 hydrocarbons under nonoxidative conditions.

Excellent catalytic effect of LaNi5 on hydrogen storage properties for aluminium hydride at mild temperature

The catalytic effect of rare-earth hydrogen storage alloy is investigated for dehydrogenation of alane, which shows a significantly reduced onset dehydrogenation temperature (86 °C) with a high-purity hydrogen storage capacity of 8.6 wt% and an improved dehydrogenation kinetics property (6.3 wt% of dehydrogenation at 100 °C within 60 min). The related mechanism is that the catalytic sites on the surface of the hydrogen storage alloy and the hydrogen storage sites of the entire bulk phase of the hydrogen storage reduce the dehydrogenation temperature of AlH3 and improve the dehydrogenation kinetic performance of AlH3. This facile and effective method significantly improves the dehydrogenation of AlH3 and provides a promising strategy for metal hydride modification.

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.

Enhanced hydrogen-storage properties of MgH2 by Fe–Ni catalyst modified three-dimensional graphene

High dehydrogenation temperature and slow dehydrogenation kinetics impede the practical application of magnesium hydride (MgH2) serving as a potential hydrogen storage medium. In this paper, Fe–Ni catalyst modified three-dimensional graphene was added to MgH2 by ball milling to optimize the hydrogen storage performance, the impacts and mechanisms of which are systematically investigated based on the thermodynamic and kinetic analysis. The MgH2+10 wt%Fe–Ni@3DG composite system can absorb 6.35 wt% within 100 s (300 °C, 50 atm H2 pressure) and release 5.13 wt% within 500 s (300 °C, 0.5 atm H2 pressure). In addition, it can absorb 6.5 wt% and release 5.7 wt% within 10 min during 7 cycles, exhibiting excellent cycle stability without degradation. The absorption-desorption mechanism of MgH2 can be changed by the synergistic effects of the two catalyst materials, which significantly promotes the improvement of kinetic performance of dehydrogenation process and reduces the hydrogen desorption temperature.

Enhanced hydrogen storage properties of NaBH4–Mg(BH4)2 composites by NdF3 addition

As two important members of complex hydrides, Mg(BH4)2 and NaBH4 have a high gravimetric capacity (14.9 and 10.8 ​wt%, respectively). In this study, the Mg(BH4)2 was synthesized by the ion exchange method. Afterwards, the Mg(BH4)2 and NaBH4 composites with different amounts (30, 40 and 50 ​wt%) of NdF3 were prepared by mechanical milling. Effects of the NdF3 on the microstructural evolution and hydrogen storage properties were investigated. The results show that NdF3 catalyst can significantly improve the dehydrogenation kinetics of the eutectic composites of NaBH4–Mg(BH4)2. The onset hydrogen desorption temperature of the composites is about 88.6 ​°C, which is about 110 ​°C lower than that of Mg(BH4)2 and NaBH4 composites. Mg(BH4)2–NaBH4-0.5NdF3 composites can released 5.2 ​wt% H2 at 250 ​°C within 30 ​min, and the dehydrogenation capacity is significantly higher than that of Mg(BH4)2–NaBH4 composites. The analysis of the dehydrogenation mechanism reveals that NdF3 takes participate in the reaction to generate NaMgF3 to promote the dehydrogenation reaction process of the composites.

Effects of Ni-loading contents on dehydrogenation kinetics and reversibility of Mg2FeH6

Although Mg2FeH6 has drawn significant attention for storing hydrogen, its sluggish kinetics during hydrogenation and poor reversibility hinder practical uses. In this work, the replacement of Fe atoms in Mg2FeH6 with Ni atoms is attempted and the material properties are investigated. A detailed study of the de/rehydrogenation kinetics and reaction mechanisms of the Ni-doped Mg2FeH6 is carried out. The effects of Ni-loading contents on kinetic properties and behaviors as well as reversibility and reaction pathways are characterized. In addition, the crystal structure of a new Ni-substituted Mg2FeH6 phase is confirmed.

Improvement of hydrogen storage characteristics of catalyst free magnesium nanoparticles prepared by wet milling

Magnesium is one of the potential candidates for on-board hydrogen storage, but slow hydrogenation kinetics and unfavourable thermodynamics limits its practical implementation. To improve the hydrogenation characteristics, nanocrystalline magnesium was prepared by a simple wet milling method without addition of heavy metal catalyst. Compared to micro-crystalline Mg, developed nanocrystalline Mg exhibits improved hydrogen storage properties showing extended plateau region in the pressure-composition-temperature curves with higher hydrogen storage capacity (6.24 wt% at 300°C). Hydrogenation and dehydrogenation kinetics is found to follow Kolmogorov−Johnson−Mehl−Avrami activation energy model confirming the involvement of nucleation-growth-impingement mechanism. Prolonged ball milling leads to quite fast hydrogenation kinetics (upto 90% of the saturation value in 15.5 minutes at 250°C) and leads to substantial decrease in the activation barrier. The activation energy for hydrogenation is found to be 68.88 kJ mol−1 for 8 hours ball milled sample. Present study established a simple and scalable method for nanocrystalline Mg, which can undergo reversible hydrogen absorption and desorption with improved performance without using any additional catalyst.

Electronic, elastic, and topological behavior of MgH2, MgTiH4, and TiH2 under pressure

This paper studies the elastic, structural, electronic, and topological behaviors of α-MgH2, β-MgH2, MgTiH4, and TiH2 under pressure by resorting to DFT-GGA’s first principle via FPLAPW-WIEN2K, ElaStic1.0, and Critic2 software. Pressure effects are studied from strain vectors generating a linear volume variation with strain. Important structural changes by the effect of pressure are evidenced. The highest strength at hydrostatic deformation was reached by TiH2; and the lowest, by α-MgH2. The elastic constants and moduli for each hydride studied showed agreement with the results reported in the literature. The TiH2 cubic lattice is shown to be structurally unstable. Hydrides showed more stability than pure crystals. The tetragonal structure of MgH2 was confirmed as more stable than its respective cubic structure; and the cubic structure of TiH2, even more so than that of the Mg hydrides, independently of their crystalline structure. Hydrides with a cubic structure showed a ductile condition, whereas those with a tetragonal structure showed a fragile one. α-MgH2 revealed an insulating character. Other hydrides studied showed a conductive character. The topology of charge density and potential energy density establishes a marked difference between the topological classes and the number of critical points (CPs) for both cubic (β-MgH2, TiH2) and tetragonal structures (α-MgH2, MgTiH4), the multiplicity of these being markedly superior in the former. The bonding character in general is covalent in the CP nucleus and both closed-layered and hydrogen-bonded in the other CPs, except in the Ti-H CP bond of the compressed structures, which bears an ionic character, unlike that of expanded structures. The incorporation of Ti to MgH2 weakens the Mg-H bond, which in turn favors the kinetics of dehydrogenation in MgTiH4.

Enhancement in hydrogenation dehydrogenation kinetics of KSiH3 by the addition of Ti-based catalysts

Recently, KSiH3 system has emerged as potential hydrogen storage alloy system due to its appropriate thermodynamic parameters and almost double reversible gravimetric hydrogen content as compared to most of the BCC alloys. The hydrogenation enthalpy value of 28 kJ mol−1 H2 propose its operation at room temperature, however, it could be operated only above 100 °C with a hydrogen storage capacity of 4.3 wt% as evidenced from experiments, due to high activation energy. The present work is designed to reduce the activation energy and investigate the effect of Ti-based catalysts i.e. Ti, TiO, Ti2O3, TiO2, TiCl3, TiF4 and TiH2 on hydrogenation properties of KSiH3 system. The results suggested the superiority of TiO over other catalysts with the reduction of activation energy to 82 kJ/mol H2 from the 130 kJ/mol H2 for the 1 h milled sample without catalyst.

Improved hydrogen storage properties of MgH2 using transition metal sulfides as catalyst

In this study, some transition metal sulfides (TiS2, NbS2, MoS2, MnS, CoS2 and CuS) are used as catalyst to enhance the hydrogen storage behaviors of MgH2. The MgH2-sulfide composites with different sulfides addition are prepared by ball-milling. The phase composition and hydrogen storage properties are studied in detail. The results confirm that all these sulfides can significantly increase the hydrogen desorption and absorption kinetics of MgH2. The MgH2–TiS2 has the best hydrogenation and dehydrogenation kinetics, followed by the MgH2–NbS2, MgH2–MnS, MgH2–MoS2, MgH2–CoS2, MgH2–CuS and MgH2. Also, the onset dehydrogenation temperature of the MgH2–TiS2 is about 204 °C, which is lower about 126 °C than that of the MgH2. The dehydrogenation activation energy can be reduced to 50.8 kJ mol−1 when doping TiS2 in MgH2. The beneficial catalytic effects of the sulfides can be ascribed to the in-situ formation of MgS, TiH2, NbH, Mo, Mn, Mg2CoH5 and MgCu2 phases.

Kinetics of dehydrogenation of riebeckite Na2Fe23+Fe32+Si8O22(OH)2: An HT-FTIR study

AbstractIn this work, we address the kinetics of dehydrogenation occurring at high temperatures (HT) in riebeckite, a sodic amphibole with the ideal composition Na2Fe23+Fe32+Si8O22(OH)2. We performed isothermal experiments on both powders and single-crystals up to 560 °C and monitored the O-H stretching signal by Fourier transform infrared (FTIR) spectroscopy. Single-crystals show an initial increase in IR absorption intensity due to increasing vibrational amplitudes of the O-H bond stretching, not observed for powders. The OH-intensities vs. time were fitted using the formalism for first-order reactions. The calculated activation energies for H+ diffusion in riebeckite are 159 ± 15 kJ/mol for powders and 216 ± 20 kJ/mol for single crystals, respectively. The exponential factor m in the Avrami-Erofeev equation obtained for crystals ranges between 1.02 and 1.31, suggesting that, unlike powders, the dehydration process in crystals is not a purely first-order reaction. This implies that a second energy barrier must be considered, i.e., diffusion of H+ through the crystal. FTIR imaging showed that H+ diffusion occurs mainly perpendicular to the silicate double-chain. Our results confirm that the release of H+ from riebeckite occurs after the irreversible Fe2+-to-Fe3+ exchange, thus at temperatures >550 °C. To be effective, the process needs the presence of external oxygen that, by interacting with H+ at the crystal surface, triggers the release of H2O molecules. This implies that oxidizing conditions are required for the amphibole to be an efficient water source at depth.

Metal-free rapid dehydrogenation kinetics and better regeneration yield of ammonia borane

Ammonia borane (AB), one of the promising hydrogen storage materials, is receiving more attention because of its high hydrogen content. However, to act as a sustainable material for hydrogen storage, regeneration from products obtained on dehydrogenation is essential. Regeneration of AB reported in literature involves the use of expensive reagents with high toxicity and environmental impact. In this work, we attempted to aid the dehydrogenation/regeneration process of pure ammonia borane as well as products obtained on thermolysis of AB, using acetone as the dehydrogenation/digestion reagent. During dehydrogenation, a total of 1.7 equivalent of hydrogen was obtained through a thermal and chemical reaction with the resultant formation of tri and tetrasubstituted borate ester. In the current work, a simple method for regeneration of AB is being demonstrated from the dehydrogenated products, which are borate esters, in this case. Using this method, an overall regeneration yield, i.e., from starting material AB→ dehydrogenated products→ regenerated material AB is observed to be 68%. The conversion yield of regenerated AB, starting from dehydrogenated products, was found to be 83%, and that into hydrazine borane (HzB) to be 15% (which can also act as hydrogen source).

The dehydrogenation kinetics and reversibility improvements of Mg(BH4)2 doped with Ti nano-particles under mild conditions

Magnesium borohydride, Mg(BH4)2, is ball-milled with Ti nano-particles. Such catalyzed Mg(BH4)2 releases more hydrogen than pristine Mg(BH4)2 does during isothermal dehydrogenation at 270, 280, and 290 °C. The catalyzed Mg(BH4)2 also exhibits better dehydrogenation kinetics than the pristine Mg(BH4)2. Based on kinetics model fitting, the activation energy (Ea) of the catalyzed Mg(BH4)2 is calculated to be lower than pristine Mg(BH4)2. During partial dehydrogenation, the catalyzed Mg(BH4)2 releases 4.23 wt % (wt%) H2 for the second dehydrogenation at 270 °C, comparing to 4.05, and 3.75 wt% H2 at 280, and 290 °C. The reversibility of 4.23 wt% capacity is also one of the highest for Mg(BH4)2 dehydrogenation under mild conditions such as 270 °C as reported. 4 cycles of Mg(BH4)2 dehydrogenation are conducted at 270 °C. The capacities degrade during 4 cycles and tend to be stable at about 3.0 wt% for the last two cycles. By analyzing the hydrogen de/absorption products of the catalyzed sample, Mg(BH4)2 is found to be regenerated after rehydrogenation according to Fourier Transform Infrared (FTIR) spectroscopy. Ti nano-particles can react with Mg(BH4)2 during ball-milling and de/rehydrogenation. The products include TiH1.924, TiB, and TiB2, which can improve the dehydrogenation properties of Mg(BH4)2 from a multiple aspect.

Effect of Different Amounts of TiF3 on the Reversible Hydrogen Storage Properties of 2LiBH4-Li3AlH6 Composite.

Hydrogen is a potential green alternative to conventional energy carriers such as oil and coal. Compared with the storage of hydrogen in gaseous or liquid phases, the chemical storage of hydrogen in solid complex hydrides is safer and more effective. In this study, the complex hydride composite 2LiBH4–Li3AlH6 with different amounts of TiF3 was prepared by simple ball-milling and its hydrogen storage properties were investigated. Temperature programmed desorption and differential scanning calorimetry were used to characterize the de/rehydrogenation performance, and X-ray diffraction and scanning electron microscopy (SEM) were used to explore the phase structure and surface topography of the materials. The dehydrogenation temperature decreased by 48°C in 2LiBH4–Li3AlH6 with 15 wt% TiF3 composites compared to the composite without additives while the reaction kinetics was accelerated by 20%. In addition, the influence of hydrogen back pressure on the 2LiBH4–Li3AlH6 with 5 wt% TiF3 composite was also investigated. The results show that hydrogen back pressure between 2.5 and 3.5 bar can improve the reversible performance of the composite to some extent. With a back pressure of 3.5 bar, the second dehydrogenation capacity increased to 4.6 wt% from the 3.3 wt% in the 2LiBH4–Li3AlH6 composite without hydrogen back pressure. However, the dehydrogenation kinetics was hindered. About 150 h, which is 100 times the time required without back pressure, was needed to release 8.7 wt% of hydrogen at 3.5 bar hydrogen back pressure. The SEM results show that aluminum was aggregated after the second cycle of dehydrogenation at the hydrogen back pressure of 3 bar, resulting in the partial reversibility of the 5 wt% TiF3-added 2LiBH4–Li3AlH6 composite.

Catalytic effects of TiO2 on hydrogen storage thermodynamics and kinetics of the as-milled Mg-based alloy

The addition of transition elements as catalyst in the ball-milling process is reckoned as a very efficient method to ameliorate the hydrogen storage property of magnesium based materials. In this study, mechanical grinding was employed to prepare the Mg-based alloys La7Ce3Mg80Ni10 + x wt% TiO2 (x = 0–10) (named La7Ce3Mg80Ni10 -xTiO2 (x = 0–10)). The microstructure characterization of as-milled alloys was achieved with the help of XRD, SEM and TEM. The isothermal and non-isothermal hydrogen storing kinetics was measured by Sievert apparatus, DSC and TGA with H2 detector. Hydrogen desorption activation energies were evaluated by Arrhenius and Kissinger methods. According to the result, the as-milled alloys possess an amorphous and nanocrystalline structure. Besides, the particle size of alloy containing TiO2 obviously diminishes compared with the TiO2-free alloy, which suggests that the additive TiO2 enhances the efficiency of mechanical milling. Moreover, the as-milled (x = 5) alloy has the optimal activation property, hydrogenation and dehydrogenation kinetics, and it absorbs 4 wt% H2 in 45 s at 473 K and 3 MPa, desorbing 3 wt% H2 in 172 s at 573 K and 1 × 10−4 MPa. The effect of TiO2 content on the thermodynamics property of alloys is slight, and the absolute value of the dehydrogenation enthalpy change (ΔH) of the as-milled (x = 5) alloy is 73.03 kJ/mol. In addition, the as-milled (x = 5) alloy has the minimum dehydrogenation apparent activation energy (57.4 kJ/mol), which also explains why the as-milled (x = 5) alloy exhibits the optimal hydrogen storage property.

Tungsten(VI) oxide supported rhodium(0) nanoparticles; highly efficient catalyst for H2 production from dimethylamine borane

It reports the preparation and characterization of tungsten(VI) oxide supported rhodium(0) nanoparticles (Rh0/WO3 NPs) being used as catalysts in releasing H2 from dimethylamine borane (DMAB). The reducible nature of WO3 plays a significant role in the catalytic efficiency of rhodium(0) nanoparticles in the dehydrogenation of DMAB. The Rh0/WO3 NPs were in-situ generated from the reduction of Rh2+ ions on the surface of WO3 during the catalytic dehydrogenation of dimethylamine borane in toluene and isolated from the reaction solution after the dehydrogenation to be characterized by using SEM, TEM, XPS, ATR-IR and XRD. The results reveal the formation of Rh0 NPs with a mean particle size of 1.92 ± 0.34 nm dispersed on the surface of tungsten(VI) oxide. Rh0/WO3 NPs are found to be very active catalyst releasing 1.0 equiv. H2 per mole of dimethylamine borane under ambient conditions. Among the various WO3 supported Rh0 NPs with different metal loadings, the sample with 0.1% wt. Rh provide the record catalytic activity (TOF = 2816 h−1) which is one of the highest value ever reported for rhodium-based catalysts in H2 generation from DMAB at 60.0 ± 0.5 °C. Rh0/WO3 NPs were also reusable catalyst in dehydrogenation of DMAB retaining 55% of their initial catalytic activity in the 3rd run of the dehydrogenation reaction. Control experiments were performed at various catalyst concentrations and temperatures to investigate the kinetics of dehydrogenation and to calculate the activation parameters for the reaction.