High Hydrogen Research Articles

Characterization of alane (AlH3) thin films grown by atomic layer deposition for hydrogen storage applications

Alane (AlH3) is an increasingly favored material for hydrogen and energy storage. It has demonstrated its potential in various applications, including rocket fuel, explosives, reducing agents, and serving as a viable source of hydrogen for portable fuel cells. In this study, we present the fabrication, morphology and elemental characterization of an AlH3 thin film grown through atomic layer deposition using a dimethylethylamine alane (DMEAA; AlH3N(CH3)2(CH2CH3)) precursor. The AlH3 thin film exhibited a rough surface with a white-like appearance, forming coarse grains as observed via scanning electron microscopy. X-ray diffraction confirmed the presence of AlH3 and it was compared with an aluminum thin film. Energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy confirmed the presence of pure AlH3 under a very thin aluminum oxide surface layer. Additionally, we propose a dissociation reaction mechanism based on the DMEAA precursor. Our work contributes to the advancement of hydrogen storage materials and energy-related applications that necessitate high hydrogen storage capacity and energy efficiency.

Anaerobic hybrid-photobioreactor using phototrophic purple and green bacteria treating piggery wastewater with sulfur recovery and biogas polishing

An anaerobic hybrid-photobioreactor (AnHPBR) was performed for biogas polishing during piggery wastewater treatment. AnHPBR was exposed to high (4.45 × 105 lx) and low (450 lx) light intensities for growing purple and green sulfur phototrophs separately in each chamber of AnHBBR for soluble sulfide removals. Four phases of hydraulic retention times (HRT, h): 24, 48, 96, and 96 (with added sulfate) of piggery wastewater were operated consecutively for 351 days. Metagenomic analysis of the AnHPBR biomass confirmed that purple and green bacteria were 63–82 %, of which the species varied by HRT and sulfate loadings. In sum, 96 h HRT for AnHPBR presented the highest efficacies in removals of COD (92 %), sulfate (73 %), and sulfide (59 %). Its biogas contained high methane (75 %) and low hydrogen sulfide (0.3 %). Additionally, AnHPBR produced outflow biosolids with a stable sulfur content of 1.88 %.

Solar-assisted two-stage catalytic membrane reactor for coupling CO2 splitting with methane oxidation reaction

A two-stage catalytic membrane reactor (CMR) that couples CO2 splitting with methane oxidation reactions was constructed based on an oxygen-permeable perovskite asymmetric membrane. The asymmetric membrane comprises a dense SrFe0.9Ta0.1O3-δ (SFT) separation layer and a porous Sr0.9(Fe0.9Ta0.1)0.9Cu0.1O3-δ (SFTC) catalytic layer. In the first stage reactor, a CO2 splitting reaction (CDS: 2CO2 → 2CO + O2) occurs at the SFTC catalytic layer. Subsequently, the O2 product is selectively extracted through the SFT separation layer to the permeated side for the methane combustion reaction (MCR), which provides an extremely low oxygen partial pressure to enhance the oxygen extraction. In the second stage, a Sr0.9(Fe0.9Ta0.1)0.9Ni0.1O3-δ (SFTN) catalyst is employed to reform the products derived from MCR. The two-stage CMR design results in a remarkable 35.4% CO2 conversion for CDS at 900 °C. The two-stage CMR was extended to a hollow fiber configuration combining with solar irradiation. The solar-assisted two-stage CMR can operate stably for over 50 h with a high hydrogen yield of 18.1 mL min−1 cm−2. These results provide a novel strategy for reducing CO2 emissions, suggesting potential avenues for the design of the high-performance CMRs and catalysts based on perovskite oxides in the future.

Observational signatures of the dust size evolution in isolated galaxy simulations

We aim to provide observational signatures of the dust size evolution in the interstellar medium (ISM). In particular, we explore indicators of the polycyclic aromatic hydrocarbon (PAH) mass fraction ($q_ PAH $), defined as the mass fraction of PAHs relative to the total dust grains. In addition, we validate our dust evolution model by comparing the observational signatures from our simulations to observations. We used the hydrodynamic simulation code, GADGET4-OSAKA to model the dust properties of Milky Way-like and NGC 628-like galaxies representing star-forming galaxies. This code incorporates the evolution of grain size distributions driven by dust production and interstellar processing. Furthermore, we performed post-processing dust radiative transfer calculations with SKIRT based on the hydrodynamic simulations to predict the observational properties of the simulations. We find that the intensity ratio between 8 um and 24 um ($I_ nu um )/I_ nu um )$) is correlated with $q_ PAH $ and can be used as an indicator of the PAH mass fraction. However, this ratio is influenced by the local radiation field. We suggest the 8 um -to-total infrared intensity ratio ($ I_ nu um )/ I_ TIR $) as another indicator of the PAH mass fraction, since it is tightly correlated with the PAH mass fraction. Furthermore, we explored the spatially resolved evolutionary properties of the PAH mass fraction in the simulated Milky Way-like galaxy using $ I_ nu um )/ I_ TIR $. We find that the spatially resolved PAH mass fraction increases with metallicity at $Z due to the interplay between accretion and shattering, whereas it decreases at $Z because of coagulation. Also, coagulation decreases the PAH mass fraction in regions with a high hydrogen surface density. Finally, we compared the above indicators in the NGC 628-like simulation with those observed in NGC 628 by Herschel Spitzer and JWST . Consequently, we find that our simulation underestimates the PAH mass fraction throughout the entire galaxy by a factor of $ 8$ on average. This could be due to the efficient loss of PAHs by coagulation in our model, suggesting that our treatment of PAHs in dense regions needs to be improved.

Directional Electron Flow in a Selenoviologen-Based Tetracationic Cyclophane for Enhanced Visible-Light-Driven Hydrogen Evolution.

Directional electron flow in the photocatalyst enables efficient charge separation, which is essential for efficient photocatalysis of H2 production. Here, we report a novel class of tetracationic cyclophanes (7) incorporating bipyridine Pt(II) and selenoviologen. X-ray single-crystal structures reveal that 7 not only fixes the distances and spatial positions between its individual units but also exhibits a box-like rigid electron-deficient cavity. Moreover, host-guest recognition phenomena are observed between 7 and ferrocene, forming host-guest complexes with a 1:1stoichiometryin MeCN. 7exhibits good redox properties, narrow energy gaps, and strong absorption in the visible range (370-500 nm) due to containing two selenoviologen(SeV2+)units.Meanwhile, the femtosecond transient absorption (fs-TA) reveals that 7 has stabilized dicationic biradical, efficient charge separation, and facilitates directional electron flow to achieve efficient electron transfer due to the formation of rigid cyclophane and electronic architecture. Then, 7 is applied to visible-light-driven hydrogen evolution with high hydrogen production (132 μmol), generation rate (11 μmol/h),turnover number (221), and apparent quantum yield (1.7%), which provides a simplified and efficient photocatalytic strategy for solar energy conversion.

Solid carbonaceous materials transformation during pulverised coal and natural gas co-injection

Co-injection of coal and gaseous fuel, such as natural gas (NG), is common practice promoting pulverised coal gasification in blast furnace (BF) ironmaking. The high hydrogen content in NG makes it possible to act as cleaner reductant to reduce iron ore to produce hot metal, which will result in reduced CO2 emissions during the ironmaking process. In this work, selected parameters affecting the overall performance of the pulverised coal and natural gas co-injection system were studied using the CanmetENERGY injection test rig, including coal injection rate, natural gas rate and blast oxygen enrichment. Increase in combustion intensity promotes conversion of injected coal into solid carbonaceous material with relatively low reactivity with CO2. Hence, it reduces the competitiveness of combustion residues for oxygen in the raceway to continue the gasification process. NG co-injection reduces the coal combustion intensity but enhances the reactivity of combustion residues by competing the oxygen in the raceway.

Thermodynamic and Kinetic Regulation for Mg‐Based Hydrogen Storage Materials: Challenges, Strategies, and Perspectives

AbstractMg‐based hydrogen storage materials have drawn considerable attention as the solution for hydrogen storage and transportation due to their high hydrogen storage density, low cost, and high safety characteristics. However, their practical applications are hindered by the high dehydrogenation temperatures, low equilibrium pressure, and sluggish hydrogenation and dehydrogenation (de/hydrogenation) rates. These functionalities are typically determined by the thermodynamic and kinetic properties of de/hydrogenation reactions. This review comprehensively discusses how the compositeization, catalysts, alloying, and nanofabrication strategies can improve the thermodynamic and kinetic performances of Mg‐based hydrogen storage materials. Since the introduction of various additives leads the samples being a multiple‐phases and elements system, prediction methods of hydrogen storage properties are simultaneously introduced. In the last part of this review, the advantages and disadvantages of each approach are discussed and a summary of the emergence of new materials and potential strategies for realizing lower‐cost preparation, lower operation temperature, and long‐cycle properties is provided.

Directional Electron Flow in a Selenoviologen‐Based Tetracationic Cyclophane for Enhanced Visible‐Light‐Driven Hydrogen Evolution

Directional electron flow in the photocatalyst enables efficient charge separation, which is essential for efficient photocatalysis of H2 production. Here, we report a novel class of tetracationic cyclophanes (7) incorporating bipyridine Pt(II) and selenoviologen. X‐ray single‐crystal structures reveal that 7 not only fixes the distances and spatial positions between its individual units but also exhibits a box‐like rigid electron‐deficient cavity. Moreover, host‐guest recognition phenomena are observed between 7 and ferrocene, forming host‐guest complexes with a 1:1 stoichiometry in MeCN. 7 exhibits good redox properties, narrow energy gaps, and strong absorption in the visible range (370‐500 nm) due to containing two selenoviologen (SeV2+) units. Meanwhile, the femtosecond transient absorption (fs‐TA) reveals that 7 has stabilized dicationic biradical, efficient charge separation, and facilitates directional electron flow to achieve efficient electron transfer due to the formation of rigid cyclophane and electronic architecture. Then, 7 is applied to visible‐light‐driven hydrogen evolution with high hydrogen production (132 μmol), generation rate (11 μmol/h), turnover number (221), and apparent quantum yield (1.7%), which provides a simplified and efficient photocatalytic strategy for solar energy conversion.

Nox Emissions Assessment of a Multi Jet Burner Operated with Premixed High Hydrogen Natural Gas Blends

Abstract Decarbonization of gas turbine combustion creates a pressing demand for new technical solutions for the combustion process. While switching to hydrogen fuels may solve the problem of carbon emissions and associated pollutants it can also lead to stability issues for swirl-stabilized combustors due to its increased reactivity. However, with jet flame burner systems, the required flashback safety can be achieved with high axial flow velocities even for premixed combustion of 100% hydrogen fuel. The development of such an engineering solution, however, requires significant effort to reach the maturity of today's swirl burners. This study examines the capacity of a premixed multi-tube jet burner to manage the chemical reactivity change over a range of volumetric blends from pure natural gas to pure hydrogen fuel. NOx emissions are measured and analyzed for atmospheric tests. The changes in emissions originate not only from altered combustion chemistry but also from changes in flame shape and turbulence intensity. To get a deeper understanding of the NOx formation process, a low-order model is designed and compared to the experimental data of technically and perfectly premixed combustion tests. Parameter variations of the low-order model are conducted to assess the influences on the NOx emission production of the multi jet burner. The information on the combustion process required for the model is obtained computationally and experimentally. Therefore, flame images are recorded and analyzed.

Unlocking Quantum Catalysis in Topological Trivial Materials: A Case Study of Janus Monolayer MoSMg

The emerging field of topological catalysis has received significant attention due to its potential for high‐performance catalytic activity in the hydrogen‐evolution reaction (HER). While topological materials often possess fragile surface states, trivial topological materials not only offer a larger pool of candidates but also demonstrate robust surface states. As a result, the search for topological catalysts has expanded to include trivial schemes. In this study, a novel 2D Janus monolayer, MoSMg, which demonstrates exceptional obstructed atomic insulating behavior, is presented. Crucially, this trivial metallic topological state exhibits clean obstructed surface states, leading to a significant enhancement in catalytic performance for the HER in electrochemical processes, particularly under high hydrogen coverage. Moreover, the edge sites of this MoSMg monolayer exhibit even more superior catalytic activity, characterized by near‐zero Gibbs free energies. In these findings, the way is paved for exploring new avenues in the design of quantum electrocatalysts, especially within the realm of trivial topological materials.

Insights into microbial metabolic coordination under driving force of different conductive materials-mediated direct interspecies electron transfer during anaerobic digestion

In this study, different carbon/metal-based conductive materials (CMs) were amended in traditional anaerobic digestion (AD) system with high hydrogen partial pressure (pH2) to verify the operational feasibility of CMs-mediated direct interspecies electron transfer (DIET). Operational performances revealed that SCOD removal efficiencies and CH4 production of CMs-mediated groups including GS (graphene), CTS (carbon nanotube), BS (biochar), IS (magnetite) and MS (MnO2) were increased by 34.7 %-157.3 %, 33.0 %-154.4 %, 41.2–169.6 %, 30.7 %-146.7 % and 28.1 %-139.5 % when compared with those of control group (54.5 ± 4.1 % and 184.9 ± 12.5 mL/g·VSS). Additionally, electron transfer capacity measurement showed that the equivalent current of biochar-mediated DIET flux (7 × 10-3 A) was 102 and 109 times higher than those in magnetite-mediated and interspecies H2 transfer (IHT) conditions due to presence of abundant electron-exchanging functional groups. Furthermore, dynamic microbiome distribution and anaerobic metabolism analysis proved that genes encoding syntrophic enzymes were highly stimulated in GS, CTS and BS while genes encoding acidogenic enzymes were more expressed in IS and MS with acetate oxidizers and Methanothrix as CMs-mediated DIET participants, suggesting that metabolic coordination of fermentative bacteria could be selectively induced to cooperate with DIETers for maintaining stable operation of each CMs-mediated AD systems in high pH2 condition. Overall, this study could offer better understand on application strategies of carbon-based and metal-based CMs for inducing the distinct CMs-mediated DIET process, which further optimized selection basis of CMs and widened real application of CMs-mediated DIET.

Effect and mechanism of ionic liquid-polymer composite coating on enhancing hydrogen embrittlement resistance of X80 pipeline steel for hydrogen blended natural gas transportation

Blending hydrogen into existing natural gas pipelines is a cost-effective method for large-scale hydrogen transportation. However, high hydrogen ratios cause hydrogen embrittlement in pipeline steel, limiting transportation efficiency. Due to complex structures and harsh application conditions, existing coatings are difficult to apply on pipelines. To tackle such issues, we propose an ionic liquid-polymer composite coating using epoxy resin as coating substrate, based on the competitive adsorption of methane and hydrogen on pipeline steel. Ionic liquids with high methane selectivity were selected via quantum chemical calculation. The protective effect of coatings was characterized using hydrogen pre-charging constant strain tensile tests. Simulation and experimental results demonstrate that epoxy resin coatings reduce hydrogen embrittlement in X80 steel. Modified with selective CH4/H2 permeability ionic liquids, the epoxy resin coating enhances methane and hydrogen competitive adsorption on the steel surface, improving hydrogen embrittlement resistance. This novel coating offers a viable solution for achieving safe and high ratio hydrogen blended transportation in natural gas pipeline.

Pt cluster incorporated NiO nanoflower boosts hydrogen evolution reaction via enhanced metal support interaction

Hydrogen serves as a potent and environment friendly energy source, and developing high performance hydrogen evolution reaction (HER) electrocatalysts is crucial for water splitting. In this work, Pt nanoparticles incorporated NiO nanoflower (Pt-NiO) is synthesized using an ethylene glycol reduction method. The incorporation of Pt not only introduces extra high active sites, but also induces strong interaction between NiO and Pt. Meanwhile, the NiO nanoflower support enables the dispersion of Pt and ensure high electrochemically surface area as well as fast mass transport, which greatly improves catalytic activity of Pt-NiO. Pt-NiO-3 only requires a small overpotential of 26 mV to reach 10 mA cm−2 and the Tafel slope is only 19.49 mV dec−1. In addition, the mass activity can achieve 2000 mA mgPt−1 at an overpotential of 63 mV. Moreover, obvious bubbles can be observed in the assembled H-type for overall water splitting, and the Faraday efficiency is close to 100 %, highlighting the superiority of Pt-NiO-3. This work provides insights for designing high effective electrocatalysts for HER.

Whitening toothpastes with hydrogen peroxide concentrations vs. at-home bleaching.

To evaluate the effect of whitening toothpastes with different hydrogen peroxide (HP) concentrations on HP permeability, color change, and physicochemical properties, compared to at-home bleaching treatment. Forty-nine premolars were randomized into seven groups (n = 7): untreated (control); at-home bleaching with 10% carbamide peroxide gel (AH; 10% CP) with 14 and 28 applications of 180min each (AH [14 × 180min] and AH [28 × 180min]); three whitening toothpastes (3% HP; 4% HP and 5% HP) and 10% CP brushed 28 times for 90s each (TB [28 × 90s]). HP permeability was measured using a UV-VIS spectrophotometer and color change by a digital spectrophotometer (ΔEab, ΔE00, and ΔWID). Initial concentration, pH, and viscosity were measured through titration, digital pH meter, and rheometer, respectively. Statistical analysis included one-way ANOVA, Tukey's test, and Dunnett's test (α = 0.05). 4% HP group showed acidic pH, the lowest viscosity and the highest HP concentration into the pulp chamber (p < 0.05). The 10% CP groups had lower HP in the pulp chamber and greater color change than other groups (p < 0.05), except the 5% HP group in ΔEab and ΔE00. For ΔWID, the 10% CP AH groups showed greater whitening than other groups (p < 0.05). Whitening toothpaste with up to 5% HP resulted in higher HP permeability and less color change compared to 10% CP. Higher HP commercial concentrations in toothpaste increased whitening effect; however, acidic pH toothpastes exhibited greater HP permeability. Whitening toothpastes with high hydrogen peroxide concentrations were less effective than at-home bleaching, resulting in less color change and greater permeability of hydrogen peroxide, potentially increasing the risk of tooth sensitivity.

Lithium Fluoride Enhanced Platinum Catalytic Exchange of Hydrogen Isotopes by High Hydrogen Adsorption at Low Temperature

AbstractThe catalytic exchange of hydrogen isotopes is a promising technology for purifying recycled water in nuclear power stations. However, it remains a challenge for achieving high catalytic efficiency and stability at low temperatures. In this work, we propose a facile strategy to enhance the catalyst efficiency by introducing LiF in the Pt/Ti3AlC2 (Pt−5‐LiF/Ti3AlC2). The incorporation of LiF significantly achieves high catalytic exchange efficiency of 92 % and a turnover frequency of 28.1 h−1, which are more than twice that of Pt/Ti3AlC2. The structure‐activity relationship analysis reveals that the introduction of LiF substantially enhanced the hydrogen adsorption capacity of the catalyst and further improved the performance of the catalysts. Moreover, this LiF‐added strategy is also applicable to other Pt‐based catalysts such as Pt/Al2O3 and Pt/activated carbon. This work provides a novel catalyst design strategy for high‐efficiency catalytic exchange of hydrogen isotopes.

Boosting the Performance of Aluminum-Air Batteries by Interface Modification.

The large-scale application of aqueous Al-air batteries is highly restricted by the performance of Al anodes. The severe self-corrosion and hydrogen evolution of the Al anode in a concentrated alkaline electrolyte are the main reason. Here, aimed at relieving side reactions and enhancing the utilization of metal Al, we propose a hybrid electrolyte additive of 2-mercaptobenzothiazole (MBT) and ZnO to form a protective film at the anode/electrolyte interface and to decrease the hydrogen evolution active site. The strong absorption capability of MBT on the metal surface, along with the reduced Zn-containing layer, enables a compact protective film with high hydrogen evolution potential on the Al surface. With this benefit, the hydrogen evolution reaction (HER) inhibition efficiency is up to 83.58%, endowing a superior Al-air battery with an energy density of 2376.71 Wh kgAl-1 under a current density of 25 mA cm-2. The conception of constructing a hybrid protective film on the metal surface not only favors the development of metal-air batteries but also facilitates metal corrosion protection.

Enhanced bimetallic CuCo nanoparticles on nitrogen-doped carbon for selective hydrogenation of furfural to furfuryl alcohol through strong electronic interactions

Bimetallic CuCo catalysts with different Cu to Co ratios on N-doped porous carbon materials (N-C) were achieved using impregnation method and applied in the hydrogenation of furfural (FAL) to furfuryl alcohol (FOL). The high hydrogenation activity of FAL over Cu1Co1/N-C was originated from the synergistic interactions of Cu and Co species, where Co0 and Cu0 simultaneously adsorb and activate H2, and Cu+ served as Lewis acid sites to activate C═O. Meanwhile, electrons transfer from Cu to Co promoted the formation of Cu+. In situ Fourier transform infrared spectroscopy analysis indicated that Cu1Co1/N-C adsorbed FAL with a tilted η1-(O) configuration. The superior Cu1Co1/N-C showed excellent adsorbed ability towards H2 and FAL, but weak adsorption for FOL. Therefore, Cu1Co1/N-C possessed 93.1% FAL conversion and 99.0% FOL selectivity after 5 h reaction, which also exhibited satisfactory reusability in FAL hydrogenation for five cycles.

Room temperature catalytic upgrading of unpurified lignin depolymerization oil into bisphenols and butene-2

Lignin is the largest source of renewable aromatics on earth. Despite numerous techniques for lignin depolymerization into mixtures of valuable monomers, methods for their upgrading into final products are scarce. The state of the art upgrading methods generally rely on catalytic funneling, requiring high temperatures, catalyst loadings and hydrogen pressure, and lead to the loss of functionality and bio-based carbon content. Here an alternative approach is presented, whereby the target monomers are selectively converted in unpurified mixtures into easily separable final products under mild conditions. We use reductive catalytic fractionation of wood to convert lignin into iso-eugenol and propenyl syringol enriched oil followed by an olefin metathesis to yield bisphenols and butene-2, thus, valorizing all bio-based carbons. To further demonstrate the synthetic utility of the obtained bisphenols we converted them into polyesters with a high glass transition temperature (Tg = 140.3 °C) and thermal stability (Td50% = 330 °C).

Hydrogen Production in Microbial Electrolysis Cells Using an Alginate Hydrogel Bioanode Encapsulated with a Filter Bag.

The bacterial anode of microbial electrolysis cells (MECs) is the limiting factor in a high hydrogen evolution reaction (HER). This study focused on improving biofilm attachment to a carbon-cloth anode using an alginate hydrogel. In addition, the modified bioanode was encapsulated by a filter bag that served as a physical barrier, to overcome its low mechanical strength and alginate degradation by certain bacterial species in wastewater. The MEC based on an encapsulated alginate bioanode (alginate bioanode encapsulated by a filter bag) was compared with three controls: an MEC based on a bare bioanode (non-immobilized bioanode), an alginate bioanode, and an encapsulated bioanode (bioanode encapsulated by a filter bag). At the beginning of the operation, the Rct value for the encapsulated alginate bioanode was 240.2 Ω, which decreased over time and dropped to 9.8 Ω after three weeks of operation when the Geobacter medium was used as the carbon source. When the MECs were fed with wastewater, the encapsulated alginate bioanode led to the highest current density of 9.21 ± 0.16 A·m-2 (at 0.4 V), which was 20%, 95%, and 180% higher, compared to the alginate bioanode, bare bioanode, and encapsulated bioanode, respectively. In addition, the encapsulated alginate bioanode led to the highest reduction currents of (4.14 A·m-2) and HER of 0.39 m3·m-3·d-1. The relative bacterial distribution of Geobacter was 79%. The COD removal by all the bioanodes was between 62% and 88%. The findings of this study demonstrate that the MEC based on the encapsulated alginate bioanode exhibited notably higher bio-electroactivity compared to both bare, alginate bioanode, and an encapsulated bioanode. We hypothesize that this improvement in electron transfer rate is attributed to the preservation and the biofilm on the anode material using alginate hydrogel which was inserted into a filter bag.

Hydrogen adsorption, migration and desorption on amorphous carbon: A DFT and AIMD study

Physisorption is the general dominating adsorption mode on pure carbonaceous materials. In this study, we examined if chemisorbed hydrogen can be accomplished without incorporating metals on carbon surfaces. We constructed two 100-atom amorphous carbon (a-C) models with different microenvironments (42 % 2-fold, 52 % 3-fold, and 6 % 4-fold coordinated carbon atoms and 18 % 2-fold and 82 % 3-fold, respectively) using ab initio molecular dynamics (AIMD) simulations to mimic activated carbon samples in reality. The structural, energetic, electronic structure and kinetic properties of hydrogen adsorption, migration, and desorption on the a-C surfaces were analyzed using density functional theory (DFT) and AIMD calculations, which showed that: (1) hydrogen molecules could spontaneously dissociate on the convex side of 2-fold coordinated carbon atoms. Physisorption of hydrogen molecules mainly took place on 3-fold coordinated carbon atoms. (2) Regarding the multiple hydrogen adsorption, the entire a-C model could uptake around 156 hydrogen atoms with the adsorption energy per hydrogen atom about −0.70 to −0.60 eV at high hydrogen pressure. In addition, we found that the average individual adsorption energy of a single hydrogen atom on different carbon atoms could be used as a quick prediction for the saturated hydrogen adsorption energy. (3) The migration barrier of a hydrogen atom between two adjacent carbon atoms was about 2 eV at both low and high hydrogen coverage, indicating that hydrogen mobility on this designed a-C model was low. The desorption of a hydrogen molecule can take place at 300 K using AIMD calculation, but not for atomic hydrogen desorption. In this work, we demonstrated that hydrogen chemisorption could take place on this designed a-C without the decoration of metal particles to enhance hydrogen adsorption amounts. The materials design to balance hydrogen chemisorption, migration, and desorption shall be considered in the future.