Size-dependent catalytic activity of cobalt phosphides for hydrogen evolution reaction
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Li, Xiaoke↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Electrochemically engineered domain: nickel–hydroxide/nickel nitride composite for alkaline HER electrocatalysis
The impact ofin situelectrooxidation in a Ni 3 N electrocatalyst on its hydrogen evolution activity and electrochemical stability was investigated in alkaline media.
Chemistry↗
Universal pH electrocatalytic hydrogen evolution with Au-based high entropy alloys
The synthesis of AuPdFeNiCo high entropy alloy nanoparticles is reported. These nanoparticles exhibit robust hydrogen evolution activity quantified over a broad pH range, with higher activity than any of the unary metal counterparts.
Chemistry↗
Decoupling electrode kinetics to elucidate reaction mechanisms in alkaline water electrolysis
Alkaline water electrolysis (AWE) presents key advantages, including reduced material costs, enhanced operational stability, and compatibility with non-precious metal catalysts, positioning it as a scalable route for hydrogen production. In this study, we introduce a minimally invasive single-cell configuration incorporating a reference electrode via diaphragm extension to form an internal ion channel. This setup, combined with an interfaced potentiostat and auxiliary electrometer, enables real-time, independent monitoring of anode and cathode behavior, offering high-resolution electrochemical diagnostics. While it is well established that the hydrogen evolution reaction (HER) exhibits sluggish kinetics in alkaline media, our study reveals that this limitation persists even in practical AWE systems where nickel-based substrates are used as electrodes. This observation is supported by both experimental data and voltage breakdown modeling. Arrhenius-type analysis reveals that localized electric fields induced by catalysts shift the reaction kinetics from classical Butler–Volmer behavior toward a Marcus-like regime, where interfacial molecular dynamics and bimolecular charge transfer dominate. We propose a semi-empirical model and a surficial reaction mechanism to describe these dynamics. This work underscores the critical need for cathode innovation and provides a rational framework for designing advanced catalysts and electrode architectures to optimize AWE performance.
08 HYDROGEN↗
Cumene-to-Phenol Process Mediated by Bromine Radicals through Photoinduced Ligand-to-Metal Charge Transfer
Selective C–H activation via hydrogen atom transfer (HAT) has gained significant interest recently. One industrial application for HAT can be found in the tertiary benzylic C–H bond of cumene for producing phenol, a versatile chemical feedstock for various industries. However, the overall phenol yield remains low using the existing Hock process due to the poor selectivity towards the key reaction intermediate, cumene hydroperoxide (CHP). Here, in this work, we demonstrate an efficient strategy for phenol production through photooxidation of cumene to CHP using iron bromide under blue light irradiation, where bromine radicals (generated in situ via ligand-to-metal charge transfer) are used as hydrogen atom abstractors. Mechanistic studies revealed the cumene-to-CHP conversion occurred via a tertiary C–H bond abstraction by a radical mechanism, and the acetic acid and water additives increased CHP selectivity through stabilizing peroxides. The cumene-phenol process achieved up to 88% yield of CHP in 1 hour and could be used with a wide range of substrates. We thus developed a selective, mild, and efficient phenol production method using iron bromide under photooxidative conditions.
HAT↗
First-principles design of a single-atom–alloy propane dehydrogenation catalyst
The complexity of heterogeneous catalysts means that a priori design of new catalytic materials is difficult, but the well-defined nature of single-atom–alloy catalysts has made it feasible to perform unambiguous theoretical modeling and precise surface science experiments. Herein we report the theory-led discovery of a rhodium-copper (RhCu) single-atom–alloy catalyst for propane dehydrogenation to propene. Although Rh is not generally considered for alkane dehydrogenation, first-principles calculations revealed that Rh atoms disperse in Cu and exhibit low carbon-hydrogen bond activation barriers. Surface science experiments confirmed these predictions, and together these results informed the design of a highly active, selective, and coke-resistant RhCu nanoparticle catalyst that enables low-temperature nonoxidative propane dehydrogenation.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Nevada National Security Site - E-Tunnel Wastewater Disposal System: Fourth Quarter 2019
This report includes the results of monthly inspections and monitoring for October, November, and December 2019. Monthly inspections and monitoring were conducted on October 15, November 26, and December 18, 2019. Inspections include a visual assessment of the berms, ponding, water levels relative to the overflow pipes, tunneling or burrowing into the berms, soil conditions on and around the berms, erosion or sloughing of the slopes of the berms, seeps at the toe of the berms, deep-rooting botanicals on the berms, and fencing. Monthly monitoring includes measurements of the instantaneous flow rate, hydrogen ion activity (pH), and specific conductance of the E-Tunnel Wastewater Disposal System (ETDS) discharge. Annual sample results of the effluent water from the ETDS are also included in this report. The effluent sample was collected on September 11, 2019, and analyzed for the parameters listed in Table 1-B of Permit NEV 96021. In addition, Permit NEV 96021 requires the collection and analysis of representative groundwater samples from Well ER 12-1 every 24 months. This summary report provides the information pertaining to the sampling and analysis of groundwater samples collected on April 10, 2019.
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Nevada National Security Site E-Tunnel Wastewater Disposal System Quarterly Monitoring Report, Water Pollution Control Permit NEV 96021 (First Quarter Calendar Year 2020)
This report includes the results of monthly inspections and monitoring for January, February, and March 2020. Monthly inspections and monitoring were conducted on January 15, February 12, and March 17, 2020. Inspections include a visual assessment of the berms, ponding, water levels relative to the overflow pipes, tunneling or burrowing into the berms, soil conditions on and around the berms, erosion or sloughing of the slopes of the berms, seeps at the toe of the berms, deep-rooting botanicals on the berms, and fencing. Monthly monitoring includes measurements of the instantaneous flow rate, hydrogen ion activity (pH), and specific conductance of the E-Tunnel Wastewater Disposal System discharge.
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Identification of Hydrogen Rail Maintenance Facility Hazards
Maintenance facilities for hydrogen rail, the activities conducted within such facilities, and how these activities differ from ordinary rail or hydrogen vehicle maintenance are currently being considered for the hazards specific to hydrogen. By performing a hazard and operability study (HAZOP) on numerous potential maintenance and repair scenarios, select low, medium, and high risk hazards relevant to hydrogen rail systems in such environments have been identified. The analysis resulted in 79 unique HAZOP scenarios: one scenario in the high risk category, 43 in the medium risk category, and 35 in the low risk category. Notably, large accidental releases of hydrogen due to tank rupture, aberrant defueling processes, or relief device opening within a facility are important low likelihood consequences that should nevertheless be appropriately prevented and mitigated.
08 HYDROGEN↗
Activated magnesium boride materials for hydrogen storage
Some embodiments described herein provide for methods for synthesizing magnesium borohydride from hydrogenation of magnesium boride at moderate temperature and pressure in the presence of a modifier. The modifier may be in form of hydrides, liquid hydrogen carriers, ammonia borane, metallic species, croconate anion based materials, ethers, amines or imines, metal carbides, borides, graphene, arenes, magnesium, aluminum, calcium or ionic liquids. Some embodiments provide for charging magnesium boride in presence of a modifier at high pressure hydrogen while simultaneously heating the material. The modification in some instances may lead to an improved magnesium boride product with enhanced properties for application in other hydrogen storage systems.
Severa, Godwin↗
Methane and methane-carbon dioxide activated synergystic biomass gasification for hydrogen rich syngas production
In one aspect, the disclosure relates to methods for biomass gasification to produce sustainable and renewable alternatives to fossil fuels including, but not limited to syngas having a high H2 content. The method can produce an H2/CO ratio close to 2:1, which is desirable for further chemical or transportation fuel synthesis. In another aspect, the methods disclosed herein have high yields and make use of agricultural and industrial waste (e.g., hardwood pellets and grain stovers) as starting materials. In a further aspect, the methods disclosed herein can produce useful byproducts including, but not limited to, carbon nanofibers (CNF). This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
Hu, Jianli↗
Hydrogen Evolution on Restructured B-Rich WB: Metastable Surface States and Isolated Active Sites
Borides have been recently identified to be a class of earth-abundant and low-cost materials that are surprisingly active toward oxidative dehydrogenation and hydrogen evolution reaction (HER) catalysis. Here, we explain from first-principles calculations the HER activity of WB, an industrial material known for its superior physical properties and chemical inertness. We find that, compared to bulk termination, a major surface reconstruction takes place, leading to the off-stoichiometric B-rich surface termination that contains the active sites. The hydrogen adsorbate configurations are further investigated under various adsorbate coverages. Many competing configurations appear to be accessible in reaction conditions, and thus, a grand canonical ensemble is established to describe the catalytic system. A phase diagram of adsorbate coverages is constructed as a function of pH and the applied potential. A complex reaction network is presented based on the ensemble-averaged reaction rates, and the electrocatalytic activities are evaluated under different overpotentials. Here, the major contributors to the activity are found to be a few metastable surface states with a distinct electronic structure that are only accessible at high adsorbate coverages in reaction conditions. In addition, while the activity of the dominant active site is nearly the same as that on the unreconstructed WB, the B-rich formations play an important role of isolating the active sites and preventing the passivation of the surface with H 2 bubble formation.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Computational Investigation of the Role of Active Site Heterogeneity for aSupported Organovanadium(III) Hydrogenation Catalyst
A crucial consideration for supported heterogeneous catalysts is the nonuniformity of the active sites, particularly for supported organometallic catalysts. Standard spectroscopic techniques, such as X-ray absorption spectroscopy, reflect the nature of the most populated sites, which are often intrinsically structurally distinct from the most active catalytic sites. Additionally, with computational models, often, only a few representative structures are used to depict catalytic active sites on a surface, even though there are numerous observable factors of surface heterogeneity that contribute to the kinetically favorable active species. A previously reported study on the mechanism of a surface organovanadium-(III) catalyst [(SiO 2 )V III (Mes)(THF)] for styrene hydrogenation yielded two possible mechanisms: heterolytic cleavage and redox cycling. These two mechanistic scenarios are challenging to differentiate experimentally since the kinetic readouts of the catalyst are identical. To showcase the importance of modeling surface heterogeneity and its effect on catalytic activity, density functional theory (DFT) computational models of a series of potential active sites of [(SiO 2 )V III (Mes)(THF)] for the reaction pathways are applied in combination with kinetic Monte Carlo (kMC) simulations. Computed results were then compared to the previously reported experimental kinetic study: (1) DFT free-energy reaction pathways indicated the likely active site and pathway for styrene hydrogenation, a heterolytic cleavage pathway requiring a bare tripodal vanadium site. (2) From the kMC simulations, a mixture of different bond lengths from the support oxygen to the metal center was required to qualitatively describe the experimentally observed kinetic aspects of a supported organovanadium(III) catalyst for olefin hydrogenation. This work underscores the importance of modeling surface heterogeneity in computational catalysis.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Active magnetic regenerative processes and systems employing hydrogen as heat transfer fluid and process gas
A system including:an active magnetic regenerative refrigerator apparatus that includes a high magnetic field section in which a hydrogen heat transfer fluid can flow from a cold side to a hot side through at least one magnetized bed of at least one magnetic refrigerant, and a low magnetic field or demagnetized section in which the hydrogen heat transfer fluid can flow from a hot side to a cold side through the demagnetized bed;a first conduit fluidly coupled between the cold side of the low magnetic field or demagnetized section and the cold side of the high magnetic field section; anda second conduit fluid coupled to the first conduit, an expander and at least one liquefied hydrogen storage module.
Holladay, Jamie D.↗
Inverse ZrO 2 /Cu as a highly efficient methanol synthesis catalyst from CO 2 hydrogenation
Enhancing the intrinsic activity and space time yield of Cu based heterogeneous methanol synthesis catalysts through CO 2 hydrogenation is one of the major topics in CO 2 conversion into value-added liquid fuels and chemicals. Here we report inverse ZrO 2 /Cu catalysts with a tunable Zr/Cu ratio have been prepared via an oxalate co-precipitation method, showing excellent performance for CO 2 hydrogenation to methanol. Under optimal condition, the catalyst composed by 10% of ZrO 2 supported over 90% of Cu exhibits the highest mass-specific methanol formation rate of 524 g MeOH kg cat -1 h -1 at 220°C, 3.3 times higher than the activity of traditional Cu/ZrO 2 catalysts (159 g MeOH kg cat -1 h -1 ). In situ XRD-PDF, XAFS and AP-XPS structural studies reveal that the inverse ZrO 2 /Cu catalysts are composed of islands of partially reduced 1–2 nm amorphous ZrO 2 supported over metallic Cu particles. The ZrO 2 islands are highly active for the CO 2 activation. Meanwhile, an intermediate of formate adsorbed on the Cu at 1350 cm -1 is discovered by the in situ DRIFTS. This formate intermediate exhibits fast hydrogenation conversion to methoxy. The activation of CO 2 and hydrogenation of all the surface oxygenate intermediates are significantly accelerated over the inverse ZrO 2 /Cu configuration, accounting for the excellent methanol formation activity observed.
36 MATERIALS SCIENCE↗
Hydrogen R&D at NREL
This presentation provides an overview of the hydrogen R&D activities at NREL, including make, store, move, and use hydrogen. At NREL, our research spans the advanced water splitting materials (AWSM) and hydrogen storage R&D, performed within the HydroGEN and HyMARC Energy Materials Networks (EMN), respectively, to the materials integration and scale up work done within the H2NEW consortium, to fuel cell R&D within the M2FCT consortium, to stack and systems testing at the MW-level. These R&D activities are funded by U.S. Department of Energy Hydrogen and Fuel Cell Technologies Office.
08 HYDROGEN↗
Hydrogen storage in complex hydrides: past activities and new trends
Abstract Intense literature and research efforts have focussed on the exploration of complex hydrides for energy storage applications over the past decades. A focus was dedicated to the determination of their thermodynamic and hydrogen storage properties, due to their high gravimetric and volumetric hydrogen storage capacities, but their application has been limited because of harsh working conditions for reversible hydrogen release and uptake. The present review aims at appraising the recent advances on different complex hydride systems, coming from the proficient collaborative activities in the past years from the research groups led by the experts of the Task 40 ‘Energy Storage and Conversion Based on Hydrogen’ of the Hydrogen Technology Collaboration Programme of the International Energy Agency. An overview of materials design, synthesis, tailoring and modelling approaches, hydrogen release and uptake mechanisms and thermodynamic aspects are reviewed to define new trends and suggest new possible applications for these highly tuneable materials.
Dematteis, Erika Michela (ORCID:0000000236804196)↗