Evidence of catalytic production of hot atomic hydrogen in RF generated hydrogen/helium plasmas

A study of the line shapes of hydrogen Balmer series lines in RF generated low pressure He/H₂ plasmas produced results suggesting a catalytic process between helium and hydrogen species results in the generation of ‘hot’ (ca. 28 eV) atomic hydrogen. Even far from the electrodes ‘hot’ atomic hydrogen was predominant in He/H₂ plasmas. Line shapes, relative line areas of cold and hot atomic hydrogen (hot/cold > 2.5), were very similar for areas between the electrodes and far from the electrodes for these plasmas. In contrast, in Xe/H₂ only ‘warm’ (<5 eV) hydrogen (warm/cold < 1.0) was found between the electrodes, and only cold hydrogen away from the electrodes. Earlier postulates that preferential hydrogen line broadening in plasmas results from the acceleration of ionic hydrogen in the vicinity of electrodes, and the special charge exchange characteristics of Ar/H₂+ are clearly belied by the present results that show atomic hydrogen line shape are similar for He/H₂ plasmas throughout the relatively large cylindrical (14 cm ID × 36 cm length) cavity.     

Two-temperature chemically-non-equilibrium modeling of argon induction plasmas with diatomic gas

A non-equilibrium modeling of argon–oxygen and argon–hydrogen induction thermal plasmas was performed without thermal and chemical equilibrium assumptions. Reaction rates of dissociation and recombination of diatomic gas and ionization were taken into account with two-temperature modeling. A substantial deviation from LTE exists near the torch wall in argon–oxygen induction plasmas under atmospheric pressure, while small deviation in argon–hydrogen plasmas results from the large collision frequency between electrons and hydrogen atoms.     

What governs the transition to a sustainable hydrogen economy? Articulating the relationship between technologies and political institutions

There is a lack of integrated knowledge on the transition to a sustainable energy system. The paper focuses on the relationship between technologies and institutions in the field of hydrogen from the perspective of political theory. The paper unfolds four paradigms of governance: ‘Governance by policy networking’, Governance by government’, ‘Governance by corporate business’, and ‘Governance by challenge’, and looks into the major line of argument in support of these paradigms and into their possible bias with respect to hydrogen options. Each of these paradigms reveals an institutional bias in that it articulates specific opportunities for collaboration and competition in order to stimulate the transition to a sustainable hydrogen economy. The paper makes the observation that there is a compelling need to reframe fashionable discourse such as the necessary shift from government to governance or from government to market. Instead, specific questions with respect to the impact of guiding policy frameworks on innovation will highlight that neither ‘neutral’ nor ‘optimal’ frameworks for policy making exist, where competing hydrogen options are at stake. The identification of paradigms of governance maybe considered a methodological device for (participator) policy analysis.     

Non-stationary luminescent methods for studying the interaction of hydrogen atomic with ZnS:Tm3+ surface

The results of studying the interaction H atoms with ZnS–Tm³⁺ surface using the phenomena of heterogeneous chemiluminescence (HCL) are presented. HCL is luminescence excited in the strongly exothermic interaction acts of hydrogen atoms on the surface. The kinetic and nonstationary characteristics of luminescence are studied in depending on the excitation conditions, which serve as light indicators of physicochemical processes, occurring on the surface. The interaction parameters of hydrogen atoms with the surface of zinc sulphide: cross-sections, frequency factors, activation energies based on kinetic and non-stationary characteristics of HCL are determined.     

Revealing market adaptation to a low carbon transport economy: Tales of hydrogen futures as perceived by fuzzy cognitive mapping

In-depth understanding of target user groups' preferences can inform the design of effective public policies for hydrogen in a competitive mobility market. Our paper attempts a re-examination of the issue based on two novelties: First, fuzzy cognitive mapping, a soft computing technique for analysing complex decision making problems, is for the first time applied in this field to elicit human cognitive structures. Secondly, hydrogen market segmentation is studied by clustering involved agents in: lay people (‘demand’), automobile salesmen (‘supply’) and experts.     

Application of the Cplex-isoelectronic theory to electrocyclisations,sigmatropic rearrangements,cheletropic reactions and antiaromaticity: Consistent with Santilli's hadronic chemistry

The recently proposed Cplex-isoelectronic theory is applied to electrocyclisation/ring opening reactions, sigmatropic rearrangements, cheletropic reactions and antiaromaticity. The Cplex-isoelectronic theory is consistent with the experimental data and makes different predictions from the present quantum chemical methods in some cases, namely a stepwise pathway for the conrotatory photochemical ring opening of 1,3-cyclohexadiene, a concerted photochemical electrocyclisation for 1,3-cyclohexadiene via disrotatory motion, a concerted suprafacial [1,5] sigmatropic shift with inversion for norcaradiene, a concerted suprafacial [1,3] carbon shift with inversion and retention, a concerted suprafacial photochemical [1,5] hydrogen migration, a concerted photochemical [3,3] shift, stabilisation of cyclic 4nπ$4n\pi$ electron systems by delocalisation and their excess energy is due only to electronic repulsion and strain, the monohomocyclopropenium and cyclopropenyl cations are not ‘aromatic’. The available empirical evidence is consistent with these new predictions. This finding is consistent with Santilli's hadronic chemistry which proposes that the present quantum chemical theories require the addition of a small correction factor for molecules with two or more electrons. It is also consistent with the fact that it is impractical to calculate an exact representation for complex chemical systems using quantum based methods. Replacing double bonds with strained systems, such as the norbornene ring, is predicted to convert stepwise pathways to concerted.     

First-principles study of single atom adsorption on capped single-walled carbon nanotubes

The effects of hydrogen, oxygen, and nitrogen atomic chemisorption on capped armchair (5, 5) single-walled carbon nanotubes (SWCNT) are investigated by first-principles calculations based on the density functional theory aimed at the CNT based fuel cell applications. O or N chemisorption could break C–C bond to form doping type structure. C–C bonds are weakened from H chemisorption, favoring hydrogen storage. Both C–adatom and related C–C bond lengths fluctuate from the cap top to the tube for each type of adsorbate. There is a total amount of about 1.0 e charge transfer between N or O atom and the carbon atoms, and the catalytic activity is expected to be higher with N adsorption around the cap top. The adsorption energies and work functions also vary with the adsorption at different sites. Atomic chemisorptions are more stable on the cap than on the tube due to smaller local curvature radius. The work functions increase to above 5.0 eV with the adsorption of N and O, and drop below 4.8 eV for H adsorption, comparing with 4.89 eV for the clean tube. DOS study reveals orbital information for electrons of adatom contributed to the valence bands and the conduction bands.     

The hydrogen atom revisited

Several myths about quantum mechanics exist due to a loss of awareness of its details since its inception in the beginning of the last century or based on recent experimental evidence. It is taught in textbooks that atomic hydrogen cannot go below the ground state. Atomic hydrogen having an experimental ground state of 13.6 eV can only exist in a vacuum or in isolation, and atomic hydrogen cannot go below this ground state in isolation. However, there is no known composition of matter containing hydrogen in the ground state of 13.6 eV. It is a myth that hydrogen has a theoretical ground state based on first principles. Historically, there were many directions in which to proceed to solve a wave equation for hydrogen. The Schrodinger equation gives the observed spontaneously radiative states and the nonradiative energy level of atomic hydrogen. On this basis alone, it is justified despite its inconsistency with physical laws as well as with many experiments. A solution compatible with first principles and having first principles as the basis of quantization was never found. Scattering results required the solution to be interpreted as probability waves that give rise to the uncertainty principle which in turn forms the basis of the wave particle duality. The correspondence principal predicts that quantum predictions must approach classical predictions on a large scale. However, recent data has shown that the Heisenberg uncertainty principle as the basis of the wave particle duality and the correspondence principle taught in textbooks are experimentally incorrect. Recently, a reconsideration of the postulates of quantum mechanics, has given rise to a closed form solution of a Schrodinger-like wave equation based on first principles. Hydrogen at predicted lower energy levels has been identified in the extreme ultraviolet emission spectrum from interstellar medium. In addition, new compositions of matter containing hydrogen at predicted lower energy levels have recently been observed in the laboratory, which energy levels are achieved using the novel catalysts.     

An atomic study of hydrogen effect on the early stage oxidation of transition metal surfaces

Density functional theory (DFT) and tight-binding quantum chemical molecular dynamics (QCMD) have been applied to analyze the role of interstitial hydrogen in the process of oxygen adsorption to Ni (111) and Cr-doped Ni (111) surfaces and diffusion within these metal surfaces. The DFT calculations demonstrate that the fcc hollow and octahedral sites are the most favorable for hydrogen adsorption on the surface and subsurface, respectively. A clean metal surface has a slight inward relaxation in the topmost layer, whereas the metal atoms show outward relaxation (2%) due to interstitial hydrogen. The adsorption energies of oxygen and OH have decreased to 0.26 and 0.13 eV, respectively, and the metal atomic bond further extended in the range of 1–2% in order to hydrogen remained interstitial site. Hydrogen changes to a negatively charged in the interstitial site by receiving electron. The QCMD results reveal that the oxygen penetration depth increases when hydrogen occupy into interstitial octahedral site. The deeply diffused or interstitial hydrogen receives electrons from the metal. Additionally, interstitial hydrogen initiates the charge transfer and extends the metal atomic bond. The localized process weakens the metal–metal bonds and it makes the surface chemically active for further interaction. This process can help oxygen or other species to diffuse into the structure. As a result, the subsurface hydrogen accelerates the early stage of oxidation initiation.     

The impact of the EU ETS on the sectoral innovation system for power generation technologies – Findings for Germany

This paper provides an overview of early changes in the sectoral innovation system for power generation technologies which have been triggered by the European Emission Trading System (EU ETS). Based on a broad definition of the sector, our research analyses the impact of the EU ETS on the four building blocks ‘knowledge and technologies’, ‘actors and networks’, ‘institutions’, and ‘demand’ by combining two streams of literature, namely systems of innovation and environmental economics. Our analysis for Germany is based on 42 exploratory interviews with experts in the field of the EU ETS, the power sector, and technological innovation. We find that the EU ETS mainly affects the rate and direction of technological change of power generation technologies within the large-scale, coal-based power generation technological regime, to which carbon capture technologies are added as a new technological trajectory. While this impact can be interpreted as the defensive behaviour of incumbents, the observed changes should not be underestimated. We argue that the EU ETS’ impact on corporate CO₂ culture and routines may prepare the ground for the transition to a low-carbon sectoral innovation system for power generation technologies.     

Steam-iron process: Influence of steam on the kinetics of iron oxide reduction

The presence of low quantities of water vapour can seriously affect the kinetics of reduction of iron oxides when they are used as catalyst or to store and/or purify hydrogen from streams in the steam-iron process. Only 5% (v) of steam should be enough to inhibit the complete reduction of the solids. Since steam is a product of the reduction reaction, small amounts of water present in the reactive atmosphere can slow down the reduction itself. To account for the effect of the steam pressure during the reduction stage of the steam-iron process, two approaches have been considered and the resulting models, i.e. ‘competitive model’ and ‘inhibitive model’ have been tested against experimental measurements. Both models are based on the known Johnson-Mehl-Avrami-Kolmogorov (JMAK) theory. The ‘competitive model’, accounts for the discretization of groups of moles of iron oxide/iron reducing and oxidizing with their own reaction rates. By using the kinetic parameters obtained from independent reduction and oxidation processes, this model is not capable of predicting properly the behaviour of the solid subjected to successive reductive and oxidative cycles. On the contrary, the ‘inhibitive model’, which takes into account the hydrogen and water vapour partial pressures in a Langmuir–Hinshelwood type kinetic constant dependency, seems to be very appropriate to predict correctly the effect of the presence of water in the reducing atmosphere.     

Stabilized Li-decoration and enhanced hydrogen storage on reduced graphene oxides

Hydrogen storage properties of Li-decorated graphene oxides containing epoxy and hydroxyl groups are studied by using density functional theory. The Li atoms form Li₄O/Li₃OH clusters and are anchored strongly on the graphene surface with binding energies of −3.20 and −2.84 eV. The clusters transfer electrons to the graphene substrate, and the Li atoms exist as Li⁺ cations with strong adsorption ability for H₂ molecules. Each Li atom can adsorb at least 2H₂ molecules with adsorption energies greater than −0.20 eV/H₂. The hydrogen storage properties of Li-decorated graphene at different oxidation degrees are studied. The computations show that the adsorption energy of H₂ is −0.22 eV/H₂ and the hydrogen storage capacity is 6.04 wt% at the oxidation ratio O/C = 1/16. When the O/C ratio is 1:8, the storage capacity reaches 10.26 wt% and the adsorption energy is −0.15 eV/H₂. These results suggest that reversible hydrogen storage with high recycling capacities at ambient temperature can be realized through light-metal decoration on reduced graphene oxides.     

Management of variable electricity loads in wind – Hydrogen systems: The case of a Spanish wind farm

The main obstacles of most renewable energies are their variability and availability; thus, we propose the ‘hydrogen option’ as a means of energy management, and we study its feasibility in a specific wind farm. The installation will be capable to store electrochemically the surplus energy and return the electricity to the grid during the peak hours. The solution was to connect the system, so that we store the energy as hydrogen when the wind generation exceeds a threshold; this is done by an electrolyzer set, with the appropriate nominal power, where, besides the electrical conversion devices, we have designed a control programme for tuning the voltage and current densities to the optimal operation of the cells. To utilize the hydrogen downstream the storage subsystem, we have selected a fuel-cell and the output is finally converted to the grid requirements.     

Computational insights of alkali metal (Li / Na / K) atom decorated buckled bismuthene for hydrogen storage

The mechanism of hydrogen molecule adsorption on 2D buckled bismuthene (b-Bi) monolayer decorated with alkali metal atoms was studied using density functional theory based first principles calculations. The decorated atoms Li, Na and K exhibited distribution on surface of b-Bi monolayer with increasing binding energy of 2.6 eV, 2.9 eV and 3.6 eV respectively. The adsorption of H₂ molecule on the slabs appeared stable which was further improved upon inclusion of van der Waals interactions. The adsorption behaviour of H₂ molecules on the decorated slabs is physisorption whereas the slabs were able to bind up to five H₂ molecules. The average adsorption energy per H₂ molecules are in range of 0.1–0.2 eV which is good for practical applications. The molecular dynamics simulation also confirmed the thermodynamic stabilities of five H₂ molecules adsorbed on the decorated slabs. The storage capacity values are found 2.24 wt %, 2.1 wt %, and 2 wt %, for respective cases of Li, Na and K atoms decorated b-Bi. The analysis of the adsorbed cases pointed to electrostatic interaction of Li and H₂ molecule. The adsorption energies, binding energies, charge analysis, structural stability, density of states, and hydrogen adsorption percentage specifies that the decorated b-Bi may serve as an efficient hydrogen storage material and could be an effective medium to interact with hydrogen molecules at room temperature.     

Numerical simulation of hydrogen atom transport in thick nickel membrane using semi-empirical quantum model

The transport characteristics of hydrogen atoms are of significant interest within the energy industry. In this study, molecular dynamics (MD) simulations based on a semi-empirical quantum model are performed to examine the diffusion of hydrogen in a dense nickel membrane. The mean square displacement (MSD) and diffusion coefficients of the nickel and hydrogen atoms are derived at various temperatures in the range of 300–1800 K. The numerical results reveal the changes which take place in the transportation mechanism of the hydrogen atoms as a result of a temperature-induced variation in the lattice structure. It is shown that the transport of the hydrogen atoms changes from an interstitial diffusion mechanism at temperatures lower than 1200 K to a vacancy diffusion mechanism at temperatures of 1600–1800 K as result of a change in the nickel lattice from an ordered FCC structure to an amorphous-type structure.     

A computational study of LiBH4 clusters and enhancement of their hydrogen storage by excess electrons

The electronic structures and energies of neutral and anionic (LiBH₄)_x clusters (x = 1 – 5) have been systematically studied by using density functional theory with the B3LYP/6‐311++G(d, p) level. For investigating the importance of excess electrons on hydrogen storage capacity, the interactions between hydrogen atoms and the anionic (LiBH₄)_x clusters are also examined. The calculated formation energies of the anionic clusters show that the anionic clusters have a high thermal stability. It is found that hydrogen atoms are adsorbed on the anionic (LiBH₄)_x clusters chemically with adsorption energies in the range of ?69.13 – ?153.73 kcal/mol. The hydrogen storage capacity can be improved from 18.51% to 19.26 – 22.12% in weight percent depending on the size of various anionic (LiBH₄)_x clusters. Our calculation results show that the existence of excess electrons on the (LiBH₄)_x clusters can enhance the hydrogen storage capacity. The Mulliken charge analysis was performed to illustrate the interactions between H atoms and the anionic (LiBH₄)_x clusters. Copyright © 2016 John Wiley & Sons, Ltd.     

High-speed OH-PLIF imaging of extinction and re-ignition in non-premixed flames with various levels of oxygenation

This paper presents high-speed (HS) images of OH-PLIF collected at a repetition rate of 5 kHz along the entire length of turbulent, pilot-stabilised flames approaching global blow-off. Measurements are made in flames of compressed natural gas, CNG (similar to Sydney flames L, B, M [1]), CNG–air (similar to Sandia flames D and E [4]) as well as CNG–O₂ flames with varying O₂ concentrations. Although the HS-OH-PLIF images are only qualitative, they are found to be of sufficient spatial and temporal resolution to relay the evolution of extinction and re-ignition events. Three types of structures, common to all the flames studied here, are identified: ‘breaks’, ‘closures’ and ‘growing kernels’. Events of ‘breaks’ are counterbalanced by the occurrence of ‘closures’ which reconnect the flame sheet and maintain stable combustion particularly in the upstream regions of flames. Applying simple but effective data processing tools, it is found that the rate at which ‘breaks’ grow in the flames is faster that the rate at which they close. The measured speeds as well as the differential between the rates of growth and closures are consistent with the behaviour of edge-flames implying that these structures may play a significant role in the dynamics of extinction/re-ignition. Other contributors to re-ignition are found to be ‘growing kernels’ advected from upstream regions in the flames. As the flames approach global blow-off, these kernels become the main mechanism for re-ignition further downstream and their rate of growth is shown to vary significantly although the factors affecting such growth need to be explored further.     

Pd/NiO core/shell nanoparticles on La0.02Na0.98TaO3 catalyst for hydrogen evolution from water and aqueous methanol solution

Novel Pd/NiO core/shell nanoparticles (NPs) have been synthesized by a simple impregnation method with low temperature processing, in a ‘green’, scalable process using nontoxic chemicals. The cocatalyst consisting of a Pd core and a NiO shell formed simultaneously on the surface of La-doped NaTaO₃ photocatalyst. The Pd core both induces migration of photogenerated electrons from the bulk of the La_0.02Na_0.98TaO₃ and transfers electrons to the NiO shell. Without the NiO shell, Pd NPs show negligible H₂ production from water splitting, due to the rapid reaction between hydrogen and oxygen on the surface. On the other hand, the NiO shell allows the permeation of hydrogen and enables hydrogen reduction on Pd. The incorporation of NiO shell onto Pd remarkably enhances the photocatalytic performance of La-doped NaTaO₃ for hydrogen production from pure water. In addition, the core/shell structure can significantly enhance the stability of Pd during the photocatalytic reaction. Similar concepts could be extended to other applications, where the catalytic activity and stability are of concerns. The formation mechanism of the core/shell photocatalyst is proposed based on the high resolution transmission electron microscopy (HRTEM) images and X-ray absorption near-edge structure (XANES) analyses.     

Energy recovery and environmental concerns addressed through emergy–pinch analysis

Presented paper shows the power of emergy analysis and its ability for simultaneous consideration of different industrial resources, goods and services for the purposes of decision-making. Accompanied by the pinch concept, which by now tries to deal separately with each of the resources (energy, water, hydrogen, oxygen, etc.), the combined emergy–pinch analysis provides wide range of benefits boosted with extra inside and design guidelines improving the integration of processes and the ability to consider the ‘past’ and the ‘future’ of the resources (the effort of making them available and the effort of minimising their environmental impact). The paper presents the theoretical background of the emergy and pinch combination into general resources management technique and proves this concept on classical emergy and pinch examples accompanied with a combined resources management industrial problem considering the environmental impact of industrial activities.