Hydrogen Content Research Articles

The Role of Hydrogen in ReRAM.

Previous research on transistor gate oxides reveals a clear link between hydrogen content and oxide breakdown. This has implications for redox-based resistive random access memory (ReRAM) devices, which exploit soft, reversible, dielectric breakdown, as hydrogen is often not considered in modeling or measured experimentally. Here quantitative measurements, corroborated across multiple techniques are reported, that reveal ReRAM devices, whether manufactured in a university setting or research foundry, contain concentrations of hydrogen at levels likely to impact resistance switching behavior. To the knowledge this is the first empirical measurement depth profiling hydrogen concentration through a ReRAM device. Applying a recently-developed Secondary Ion Mass Spectrometry analysis technique enables to measure hydrogen diffusion across the interfaces of SiOx ReRAM devices as a result of operation. These techniques can be applied to a broad range of devices to further understand ReRAM operation. Careful control of temperatures, precursors, and exposure to ambient during fabrication should limit hydrogen concentration. Additionally, using thin oxynitride or TiO2 capping layers should prevent diffusion of hydrogen and other contaminants into devices during operation. Applying these principles to ReRAM devices will enable considerable, informed, improvements in performance.

Maximizing the hydrogen content for methanol steam reforming processes by using the novel pareto-based multi-objective evolutionary algorithms

This research focuses on the methanol-steam reforming (MSR) process to produce hydrogen-rich syngas. A thermodynamic equilibrium reactor was designed for the process, using the Peng-Robinson fluid package for all liquid and gas components. This research aims to reveal the collective impacts of three main parameters—reaction temperature (RT) (100–500 °C in 50 °C intervals), reactor pressure (RP) (1–7 atm in 2 atm intervals), and methanol-to-water (MtW) molar ratio (0.25, 0.5, 1, 2, and 4 atm)—on syngas composition. Additionally, Pareto-based multi-objective evolutionary algorithms (MOEAs), including Multimodal Multi-Objective Differential Evolution with Improved Crowding Distance (MMODE_ICD), Multi-Objective Slime Mould Algorithm (MOSMA), and Improved Multi-Objective Manta-Ray Foraging Optimization (IMOMRFO), were used to maximize hydrogen composition at the reactor outlet. Using these algorithms, the operating parameters for the MSR were optimized. The highest hydrogen content achieved under these conditions was 67.90% among syngases. However, it could be increased by 7.22% with MMODE_ICD, 6.92% with MOSMA, and 4.71% with IMOMRFO algorithms. Furthermore, the algorithms predicted actual data with error margins of 1.1% for MMODE_ICD, 0.28% for MOSMA, and 3.52% for IMOMRFO. In conclusion, this research demonstrates that Pareto-based multi-objective evolutionary algorithms are very effective tools for increasing hydrogen production in MSR processes.

Preparation and performance evaluation of CNF‐enhanced polyether‐modified polysiloxane defoamer

AbstractIn this article, polyether‐modified polysiloxanes were synthesized by the reaction of poly(methyl hydrogen siloxane) (PMHS) with Allyl alcohol polyether B‐400. FT‐IR, laser particle size analysis, hydrophilic–lipophilic balance (HLB) value test, and surface tension measurements were used to characterize its structures and properties. The results show that the control law for the HLB value of polyether‐modified polysiloxanes was obtained as follow: the HLB value increases with increasing hydrogen content of PMHS. When the polyether‐modified polysiloxanes were used to emulsify the polysiloxane, at the HLB value of 10.5, the average particle size of the emulsion was about 0.23 μm with a narrow particle size distribution. The emulsion has good emulsifying and dispersing properties, as well as excellent foam elimination and foam inhibition performance. When the cellulose nanofibrils (CNF) was used as a protective agent for the preparing of the polysiloxane defoamer, the stability of the emulsion does not affect, but its foam elimination and foam inhibition of emulsion can be further improved at the presence of CNF. The lowest surface tension of CNF‐enhanced polyether‐modified polysiloxane defoamer is about 22.4 mN m−1, which has good surface property. When the concentration of CNF‐enhanced polyether‐modified polysiloxane defoamer was 0.1 g L−1, the foam elimination time and foam inhibition time were 5.8 s and 38 min, respectively, at the temperature (80°C) and alkali environment (pH 13).

ВІДНОВЛЕННЯ ПАЛАДІЄВИХ МЕМБРАН ПІСЛЯ КОНТАКТУ З ВОД-НЕМ ДЛЯ ВОДНЕВО-КИСНЕВИХ ПАЛИВНИХ ЕЛЕМЕНТІВ

Annotation. Studying the deformations of palladium membranes under the influence of hydrogen, which is a relevant issue for hydrogen energy and the nuclear industry. The mechanisms of palladium membrane shape change due to hydrogen penetration and the formation of temporary gradient alloys such as α-PdHn are consid-ered. Experiments were conducted using a hydrogen-vacuum installation, where the processes of membrane satu-ration and degassing were studied at temperatures from 100°C to 360°C and hydrogen pressures from 0.01 MPa to 2.5 MPa. It was established that the change in the shape of the membrane occurs in two stages: first, a rapid bending of the membrane is observed, and then a gradual return to the initial state. It was established that the maximum change in the shape of the membrane, which occurs at a constant temperature, depends on the diffu-sion coefficient and the equilibrium solubility of hydrogen in palladium. However, when the temperature chang-es, the diffusion coefficient of hydrogen in palladium and the equilibrium concentration of hydrogen in palladi-um also change, which affects the temperature dependence of the final shape change of the membrane. This fact makes it possible to effectively determine the time of hydrogen penetration into the membrane, control the change in shape and adjust the operating modes of the fuel cell. Special attention is paid to the use of palladium alloys with copper and silver to increase the resistance of membranes to the influence of hydrogen. It is shown that such alloys have better mechanical characteristics and a longer service life at high temperatures. The effect of degassing on the restoration of membranes after contact with hydrogen was studied, the main factors affecting the efficiency of this process were determined. The results of the work confirm the need for further research on increasing the resistance of palladium membranes to deformations, as well as the development of new materials and technologies to improve their operational characteristics

Impact of Interfacial Proton Accumulation on Protonation in a Brownmillerite Oxide

AbstractElectrochemical protonation provides ways to control physical properties and even explore unprecedented phases of solid‐state materials. While how proton accumulation changes materials’ properties is investigated, how protonation of solids can be controlled and promoted remains an enigmatic puzzle. In the work reported here, the influence of electrochemical proton injection duration (tVg) is investigated on the protonation of SrCoO2.5 (SCO) films in electric‐field‐effect transistor structures with gate layers of the proton‐conducting electrolyte Nafion. The proton concentration accumulated in SCO films varies depending on the duration of the proton injection. When protons are injected in a relatively short tVg (≤ 600 s), the hydrogen concentration accumulated in SCO film increases with increasing tVg, reaching the maximum proton concentration of ≈1.9 per formula unit of SCO for the tVg = 600 s case. On the other hand, when tVg is longer than 900 s, the proton concentration decreases with tVg, implying the occurrence of counterreactions that extract protons from protonated SCO and oxidize the channel. These observations indicate that protons accumulated at the Nafion/SCO interface play a role in the protonation of SCO films and that suppressing the interfacial proton accumulation is the key to maximizing the proton concentration accumulated in SCO films.

Mathematical Modelling of the Impact of IR Laser Radiation on an Oncoming Flow of Nanoparticles with Methane

Introduction. The study is devoted to the numerical investigation of laser radiation’s effect on an oncoming two-phase flow of nanoparticles and multicomponent hydrocarbon gases. Under such exposure, the hydrogen content in the products increases, and methane is bound into more complex hydrocarbons on the surface of catalytic nanoparticles and in the gas phase. The hot walls of the tube serve as the primary source of heat for the reactive two-phase medium containing catalytic nanoparticles. Materials and Methods. The main method used is mathematical modelling, which includes the numerical solution of a system of equations for a viscous gas-dust two-phase medium, taking into account chemical reactions and laser radiation. The model accounts for the two-phase gas-dust medium’s multicomponent and multi-temperature nature, ordinary differential equations (ODEs) for the temperature of catalytic nanoparticles, ODEs of chemical kinetics, endothermic effects of radical chain reactions, diffusion of light methyl radicals CH3 and hydrogen atoms H, which initiate methaneconversion, as well as absorption of laser radiation by ethylene and particles. Results. The distributions of parameters characterizing laminar subsonic flows of the gas-dust medium in an axisymmetric tube with chemical reactions have been obtained. It is shown that the absorption of laser radiation by ethylene in the oncoming flow leads to a sharp increase in methane conversion and a predominance of aromatic compounds in the product output. Discussion and Conclusion. Numerical modelling of the dynamics of reactive two-phase media is of interest for the development of theoretical foundations for the processing of methane into valuable products. The results obtained confirm the need for joint use of mathematical modelling and laboratory experiments in the development of new resource-saving and economically viable technologies for natural gas processing.

Co-optimizing of H-curing, stress, and thermal annealing—A more effective way for realizing FEOL-BEOL compatible eMRAM chip

Metallization, plasma, and thermal annealing used in magneto-resistive random access memory integration differs significantly from traditional interconnection processes, usually resulting in the device performance deterioration of metal-oxide-silicon field-effect transistors. Commonly used methods, such as hydrogen postalloying, may not be effective to recover performance when magneto-resistive random access memory is integrated. The study focused on the interplay between hydrogen content in the dielectric films, wafer configuration induced by film stress, and thermal annealing during the chip fabrication process. Post-thermal annealing can enhance the release of hydrogen from the dielectric films, which can repair the silicon–hydrogen bond breakage resulting from magneto-resistive random access memory integration. However, this process can also worsen wafer bowing in an undesired direction which is detrimental to the performance of metal-oxide-silicon field-effect transistors. Consequently, utilizing silicon nitride with specific hydrogen content, in conjunction with post-thermal annealing, can improve effectively both p-type and n-type metal-oxide-silicon field-effect transistors. This approach holds significant potential for application in more advanced technological nodes since it is compatible with traditional process and does not require more advanced fabrication equipment. Additionally, the resulting embedded magneto-resistive random access memory chips maintain competitive magnetic tunneling junction reliability in term of endurance and reflow resistivity.

Evaluation of the antioxidant potential for three essential oils on the properties of wood pulp paper

Purpose This study aims to determine the efficiency of three types of essential oils (EOs) as antioxidants on wood pulp paper samples: camphor oil, clove oil and lavender oil. Because of the detrimental influence of the oxidation process on wood pulp paper, this type of paper suffers significant disintegration. Design/methodology/approach The evaluation methodology is based on scanning electron microscope and three directions laser microscope, the hydrogen ion concentration measurement, color change measurement using the CIELAB system and infrared spectrum analysis, as well as investigating the mechanical properties of paper as represented by tensile and elongation to determine Young’s modulus values. Findings According to the findings, camphor was an effective antioxidant for paper samples, protecting them from the damaging effects of oxidation and the impact of artificial aging processes while also improving the mechanical properties of paper. Originality/value This paper emphasizes the concept of using environmentally friendly materials derived from EOs, owing to their ease of application, lack of environmental impact, distinctive properties, low cost and distinctive properties in both curative and preventive conservation of paper manuscripts.

The Effect of Fluorine and Hydrogen Concentrations on the Chain Reaction of HF Chemical Laser

A numerical investigation has been performed to examine the effect of fluorine concentration on the chain reaction mechanisms and parameters of hydrogen fluoride (HF) chemical laser. The practical difficulties associated with this type of lasers impose that an alternative route might be quite useful. Thus, particular attention was paid to develop a computer program to investigate various processes. The results of this computer simulation program proved their credibility when compared with the little published data. This computer program is called Reaction Rate Simulation Model (RRSM). An entirely new approach to emulate the reaction mechanisms has been followed. The effectiveness of reaction rates in the processes of HF laser production has been investigated. This simulation program dealt with the percentages of the forward and reverse reactions, when a large number of reactions have been considered. In addition a large number of species have been taken into account in these reactions. From the computer program (RRSM), some valuable results could be predicted with regard to the hydrogen fluoride chemical laser.

Multi-period operation of integrated electricity and gas systems with hydrogen blending considering gas composition dynamics

Green hydrogen from renewable sources can be blended with natural gas and serves as a potentially feasible measure for contributing to the net zero energy sector. The time-varying nature of hydrogen injection, influenced by stochastic renewable generations, can result in fluctuations in gas concentrations in the entire network. It poses a potential threat to the secure regulation of integrated electricity and gas systems (IEGS). For managing the operating condition and guaranteeing the security of IEGS during operation, a multi-period operation framework with alternative gas (e.g., hydrogen) blending is developed. First, a convex gas security range is derived using the Dutton method. Then, the multi-period operation framework is devised to mitigate the impacts of alternative gas injection on gas security over the entire operational period. Both the dynamics from gas composition and gas flow are modelled, accurately describing the real-time travel of alternative gas concentrations. The dynamics in the gas mixture properties (e.g., relative density) are fully revealed with time-varying gas concentrations. To tackle the high non-convexities in the optimization problem, second-order-cone relaxation is well-tailored and firstly used in the case of varying gas compositions, making the motion equations and advective transport equations more tractable. An advanced second-order-cone sequential programming is devised to drive the relaxation tight more efficiently. Finally, our operation strategy is illustrated in IEEE and Belgium Electricity and Gas Systems. Results indicate that hydrogen concentrations take about 12.5 h to travel from the injection point to the end of the pipeline route in the Belgium gas system. By incorporating this unique characteristic into the model, operational scheduling and dispatch in IEGS can be more practical when integrating hydrogen in the future.

Hydrogen and vacancy concentrations in [formula omitted]-iron under high hydrogen gas pressure and external stress: A first-principles neural network simulation study

The metal-hydrogen-vacancy interaction in α-iron is crucial for understanding hydrogen embrittlement behavior and developing reliable materials for green gaseous hydrogen applications; however, it remains underexplored, particularly in contexts involving external stress and high hydrogen gas pressure. In this study, we performed quantitative analyses of metal-vacancy–hydrogen interactions in α-iron, measured by hydrogen solubility and the thermodynamics of vacancy–hydrogen complexes, under such challenging conditions using a reliable first-principles neural network potential. High hydrogen gas pressures reaching up to 2 GPa were investigated. As the atomic concentration surpasses approximately 0.01, hydrogen solubility is dominated by hydrogen-induced lattice distortion (primarily volumetric expansion) and the interactions between hydrogen atoms within the metal matrix, resulting in significant deviations from Sieverts’ law. Our results reveal a significant effect of shear stress on hydrogen solubility, deviating from previously used equations. Moreover, the influence of external stress on the thermodynamics of the vacancy–hydrogen complex, particularly vacancy formation free energy, is uniquely characterized by hydrogen solubility, regardless of the external stress magnitude. It thereby offers a rapid method to estimate the vacancy properties under external stress based on readily accessible external-stress-free data.

Thermal pyrolysis behavior and mechanisms of kraft lignin using methane, H2, and H2O as reactive medium: A ReaxFF molecular dynamics simulation

Biomass has become an alternative to fossil fuels due to its capacity to provide carbon-neutral energy. However, the conversion of kraft lignin into high-value chemicals remains challenging. Hydrotreatment, utilizing CH4, H2, or H2O, enables the production of high-quality liquid hydrocarbon fuels while enhancing hydrogen utilization. Reactive molecular dynamics was employed to investigate the influence of CH4, H2, and H2O as reactive medium of kraft lignin at the atomic scale. The three reactive mediums increased the maximum heavy tar yield by 8.34%, 8.07%, and 8.53% respectively, and increased the hydrogen content of pyrolysis products. Steam conditions promote the decomposition of ether bonds, while H2 and CH4 exhibit stronger inhibitory on the decomposition of carbon hexagonal rings. A crucial role of pentagonal carbon rings as intermediates in the lignin cracking process was found. These findings provide valuable insights for optimizing the pyrolysis conditions of kraft lignin to achieve the desired product yields.

The Impact of Hydrogen on Flame Characteristics and Pollutant Emissions in Natural Gas Industrial Combustion Systems

To improve energy savings and emission reduction in industrial heating furnaces, this study investigated the impact of various molar fractions of hydrogen on natural gas combustion and compared the results of the Non-Premixed Combustion Model with the Eddy Dissipation Combustion Model. Initially, natural gas combustion in an industrial heating furnace was investigated experimentally, and these results were used as boundary conditions for CFD simulations. The diffusion flame and combustion characteristics of natural gas were simulated using both the non-premixed combustion model and the Eddy Dissipation Combustion Model. The results indicated that the Non-Premixed Combustion Model provided simulations more consistent with experimental data, within acceptable error margins, thus validating the accuracy of the numerical simulations. Additionally, to analyze the impact of hydrogen doping on the performance of an industrial gas heater, four gas mixtures with varying hydrogen contents (15% H2, 30% H2, 45% H2, and 60% H2) were studied while maintaining constant fuel inlet temperature and flow rate. The results demonstrate that the Non-Premixed Combustion Model more accurately simulates complex flue gas flow and chemical reactions during combustion. Moreover, hydrogen-doped natural gas significantly reduces CO and CO2 emissions compared to pure natural gas combustion. Specifically, at 60% hydrogen content, CO and CO2 levels decrease by 70% and 37.5%, respectively, while NO emissions increase proportionally; at this hydrogen content, NO concentration in the furnace chamber rises by 155%.

Ultrafast Yttrium Hydride Chemistry at High Pressures via Non-equilibrium States Induced by an X-ray Free Electron Laser.

Controlling the formation and stoichiometric content of the desired phases of materials has become of central interest for a variety of fields. The possibility of accessing metastable states by initiating reactions by X-ray-triggered mechanisms over ultrashort time scales has been enabled by the development of X-ray free electron lasers (XFELs). Utilizing the exceptionally high-brilliance X-ray pulses from the EuXFEL, we report the synthesis of a previously unobserved yttrium hydride under high pressure, along with nonstoichiometric changes in hydrogen content as probed at a repetition rate of 4.5 MHz using time-resolved X-ray diffraction. Exploiting non-equilibrium pathways, we synthesize and characterize a hydride in a Weaire-Phelan structure type at pressures as low as 125 GPa, predicted using a crystal structure search, with a hydrogen content of 4.0-5.75 hydrogens per cation, that is enthalpically metastable on the convex hull.

Supercritical carbon dioxide likely served as a prebiotic source of methanethiol in primordial ocean hydrothermal systems

Abiotic synthesis of methanethiol through CO2 reduction is a presumptive initiation reaction of protometabolism in primordial ocean hydrothermal systems. However, reported artificial means of methanethiol production indicate the necessity of gas-phase condition, rather than aqueous-phase setting, for this prebiotic reaction to occur. Here we show that, under supercritical CO2 with a geochemically feasible concentration of hydrogen, up to 7.9% conversion of hydrogen sulfide to methanethiol is attained through a 14-day reaction at 200 °C on molybdenum sulfide catalyst deposited in a carbonate-NaCl solution. On the present ocean floor, discharges of liquid/supercritical CO2 occasionally occur in close vicinity to hydrothermal vents. Geological records of ancient seafloor suggest prevalence of such CO2 fluxes associated with hydrothermal activities. Our experimental results link these facts with the protometabolism scenario, leading to the possibility that the generation and transportation of methanethiol through the subseafloor CO2 fluxes constituted the beginning step of protometabolism in primordial ocean hydrothermal systems. Thus, the supply of supercritical-CO2-derived materials likely assisted the chemical evolution of life in combination with the known geochemical processes at the vent-ocean interface.

Quantitative analysis of hydrogen leakage flow measurement and calculation in the on-board hydrogen system pipelines

The mass flow rate of hydrogen leakage directly affects hydrogen diffusion and concentration distribution. In this paper, a test platform was constructed to measure mass flow rates during hydrogen leakage in the supply pipelines of the on-board hydrogen system. Hydrogen leakage tests were conducted under two different conditions. Mass flow rates were measured for tube fittings with various loosening angles and hydrogen supply pressures. The data were then fitted to extrapolate mass flow rates of hydrogen leakage beyond the tested conditions. Additionally, mass flow rates were measured for hydrogen supply pipelines with small holes of different shapes and sizes. The effects of pipeline size, hydrogen supply pressure, hole shape, and size on the hydrogen leakage mass flow rate were analyzed. Hydrogen leakage flow coefficients were corrected, and the accuracy of three calculation methods for hydrogen leakage flow was compared and analyzed based on the test results. The results provide a foundation for future numerical simulation models of hydrogen leakage diffusion.

Adaptive scaled boundary finite element method for hydrogen assisted cracking with phase field model

This study introduces a numerical framework for analysing hydrogen assisted cracking, employing the scaled boundary finite element method. This is the first instance where the scaled boundary finite element method is employed to model hydrogen embrittlement. The phase field model is utilized to simulate defects, complemented by adaptive meshing using polytree mesh. The ability of the scaled boundary finite element method to treat polygonal elements assists in mitigating the problem of hanging nodes that arises from polytree decomposition. The adaptive framework is developed to predict crack propagation using an initial unstructured quadrilateral mesh generated from any commercial software. The hydrogen atom concentration depends on the hydrostatic stress gradient, which is calculated by interpolating nodal hydrostatic stress with scaled boundary shape functions and taking the gradient. A staggered solution approach is adopted to concurrently tackle hydrogen transport, elasticity, and phase field equations. The methodology is validated using Mode-I edge notch specimens and analysing crack propagation from corrosion pits, with results demonstrating close agreement with existing data. Subsequently, the framework is extended to address more intricate scenarios, such as crack propagation in X-shaped plates and hydrogen transmission in tanks. As the last example, more advanced image based fracture analysis of weld structure is investigated. This example studies the possibility of analysing the hydrogen diffusion directly from TEM imagery. Moreover, we investigate how hydrogen concentration influences structural failure.

Investigating the laminar burning velocity of NH3/H2/air using the constant volume method: Experimental and numerical analysis

The fundamental combustion field of ammonia-hydrogen fuel is being extensively researched. However, studies on the laminar burning velocity (LBV) under high pressure with varying hydrogen concentration conditions are relatively scarce. This study innovatively used the constant volume method (CVM) to measure LBV of ammonia-hydrogen fuels with various hydrogen concentrations XH2 = 15%–30%, initial temperatures Ti = 298–428 K, initial pressures Pi = 1–3 bar, and equivalence ratios ϕ = 0.8–1.4. The LBV of the fuel mixture up to the temperature and pressure of 540 K and 7 bar under isentropic adiabatic assumption was determined with the CVM method. The results illustrate that the enhancing effect of hydrogen concentration on LBV is suppressed under high pressures, supporting the argument that the equivalence ratio associated with the maximum LBV is solely determined by the initial fuel composition. Chemical kinetics simulations were also analyzed including flame structure, sensitivity analysis, and reaction pathways. It indicated that the elementary reaction H + O2<=>O + OH predominantly governs the LBV of ammonia-hydrogen. An increase in hydrogen concentration intensifies this process by boosting the concentration of free radical hydrogen, albeit with a concomitant rise in NO emissions due to nitrogen-containing radical oxidation. Conversely, an increase in initial pressure diminishes NO emissions by strengthening the pathway from NO to NNH. The findings of this study enhance the LBV database of ammonia-hydrogen fuel at high pressures and high temperatures, and can further act as a reference for other experiments.

Evolution of microbial community structure during biohydrogen production process of palm oil anaerobic sludge

Anaerobic microbial communities and their functions can provide information about waste management practices, as well as reveal novel degradation metabolisms that can be utilized in wastewater treatment. This study was aimed towards sustainable palm oil industry with assessing the microbial evolution during the dark fermentative processing of palm oil anaerobic sludge and palm oil mill effluent (POME) in batch-mode over two-months with a distinct incubation time of 24 h. The process was designed using response surface methodology (RSM) by acclimatization of inoculum using POME with a chemical oxygen demand (COD) of 36 g-COD/l. The effect of mesophilic and thermophilic conditions and pH on COD removal, hydrogen content, and hydrogen yield (HY) were investigated. A potential sample was selected for microbial analysis after the first and second months of operation based on the maximum outputs achieved throughout the experiment. The bacterial community at pH 5.6 and temperature 55 ˚C with maximum hydrogen content of 64.13 %, and HY of 0.93 ml H2/g-COD was dominated by three phyla: Firmicutes, Actinobacteria, and Bacteroidota. The results obtained from high throughput pyrosequencing showed that how acclimatization period affects the microbial community structure towards Firmicutes phylum, which includes the majority of hydrogen-producing microorganisms.

Equation of State, Structure, and Transport Properties of Iron Hydride Melts at Planetary Interior Conditions

AbstractIron hydrides are a potentially dominant component of the metallic cores of planets, primarily because of hydrogen's ubiquity in the universe and affinity for iron. Using ab initio molecular dynamics, we examine iron hydrides with 0.1, 0.33, 0.5, and 0.6 mol fraction hydrogen up to 100 GPa between 3,000 and 5,000 K to describe how hydrogen content affects the melt structure, hydrogen speciation, equation of state (EOS), atomic diffusivity, and melt viscosity. We find that the addition of hydrogen decreases the average Fe–Fe coordination number and lengthens Fe–Fe bonds, while Fe–H coordination number increases. The pair distribution function of hydrogen at low pressure indicates the presence of molecular hydrogen. By tracking chemical speciation, we show that the amount of molecular hydrogen increases and the number of iron in Hx≥1Fey≥0 clusters decreases as the hydrogen concentration increases. We parameterize a pressure, volume, temperature, and composition EOS and show that the molar volume and Grüneisen parameter of the melts decrease while the compressibility and thermal expansivity increase as a function of hydrogen concentration. We find that hydrogen acts as a lubricant in the melts as the iron and hydrogen become more diffusive and the melts become more inviscid as the hydrogen concentration increases. We estimate 2.7 wt% hydrogen in the Martian core and 0.49–1.1 wt% hydrogen in Earth's outer core based on comparisons to seismic models, with the assumption that the cores are pure liquid iron‐hydrogen alloy, and we compare the small exoplanet population with mass‐radius curves of iron hydride planets.