Industrial Hydrogen Production Research Articles

Investigation on hydrogen evolution reaction performance of porous electrode prepared by laser powder bed fusion

The additive manufacturing (AM) process attracts widespread attention because it generates devices with of highly complex and precise 3D geometries that are difficult to realize using traditional fabrication methods. In this study, two kinds of porous cylindrical electrodes with different lattice structures are prepared by laser powder bed fusion (L-PBF). The influence of electrode lattice structure parameters (structure type, lattice unit size) on the efficiency of hydrogen evolution reaction (HER) is investigated. The HER efficiency of the electrode is evaluated through the energy consumption experiment and the electrochemical analysis. The results reveal that the porous electrode has significantly larger physical specific surface area and lighter weight than the solid cylindrical electrode, the electrode with the Dode Medium structure has better hydrogen evolution performance than the Rhombic Dodecahedron lattice structure under the same lattice unit size; in both structures, the electrode with 8 mm lattice aperture has better electrolytic water activity to produce hydrogen. The present work shows that AM technology can provide a flexible processing solution for high specific surface area electrodes required for large-scale and efficient industrial hydrogen production.

Electrocatalytic Water Splitting: From Harsh and Mild Conditions to Natural Seawater.

Electrocatalytic water splitting is regarded as the most effective pathway to generate green energy-hydrogen-which is considered as one of the most promising clean energy solutions to the world's energy crisis and climate change mitigation. Although electrocatalytic water splitting has been proposed for decades, large-scale industrial hydrogen production is hindered by high electricity cost, capital investment, and electrolysis media. Harsh conditions (strong acid/alkaline) are widely used in electrocatalytic mechanism studies, and excellent catalytic activities and efficiencies have been achieved. However, the practical application of electrocatalytic water splitting in harsh conditions encounters several obstacles, such as corrosion issues, catalyst stability, and membrane technical difficulties. Thus, the research on water splitting in mild conditions (neutral/near neutral), even in natural seawater, has aroused increasing attention. However, the mechanism in mild conditions or natural seawater is not clear. Herein, different conditions in electrocatalytic water splitting are reviewed and the effects and proposed mechanisms in the three conditions are summarized. Then, a comparison of the reaction process and the effects of the ions in different electrolytes are presented. Finally, the challenges and opportunities associated with direct electrocatalytic natural seawater splitting and the perspective are presented to promote the progress of hydrogen production by water splitting.

High-density ultrafine RuP2 with strong catalyst-support interaction driven by dual-ligand and tungsten-oxygen sites for hydrogen evolution at 1 A cm−2

Ultrafine and high-density RuP2 based on coordination chemistry and catalyst-support correlation shows potential for hydrogen evolution reaction (HER). Herein, the uniform and high-density W-doped ultra-small RuP2 (W0.05-RuP2@C3N4-NC) are synthesized by incorporating oxygen-bridged [WO4] tetrahedron into tetraacetic acid (EDTA)-melamino-formaldehyde (MF) ligands. EDTA-MF shows strong metal-support interaction, dedicating to the optimal dispersion, highest Ru yields, and HER activity. W atoms regulate local electron structure and coordination environment, leading to faster proton supply and hydrogen release, thus achieving 10 mA cm−2 at low overpotential of 27 mV (alkaline) and 66 mV (acidic). Notably, W0.05-RuP2@C3N4-NC maintains stability with staged 500–1000 mA cm−2 for 1000 h in alkaline, and 1000 mA cm−2 for ~300 h in acid, ascribing to the immobilized ultra-stable RuP2 nanoclusters via EDTA-MF and metal-oxygen sites. The excellent activity and stability hold promise for industrial hydrogen production, which provides deeper insights into catalyst-support interaction and reasonable design of high Ru-loading electrocatalysts.

Ultrafast Room-Temperature Synthesis of Self-Supported NiFe-Layered Double Hydroxide as Large-Current-Density Oxygen Evolution Electrocatalyst.

Water splitting is a promising sustainable technology to produce high purity hydrogen, but its commercial application remains a giant challenge due to the kinetically sluggish oxygen evolution reaction (OER). In this work, a time- and energy-saving approach to directly grow NiFe-layered double hydroxide (NiFe-LDH) nanosheets on nickel foam under ambient temperature and pressure is reported. These NiFe-LDH nanosheets are vertically rooted in nickel foam and interdigitated together to form a highly porous array, leading to numerous exposed active sites, reduced resistance of charge/mass transportation and enhanced mechanical stability. As self-supported electrocatalyst, the representative sample (NF@NiFe-LDH-1.5-4) shows an excellent large-current-density catalytic activity for OER in alkaline electrolyte, requiring low overpotentials of 190 and 220 mV to reach the current densities of 100 and 657 mA cm-2 with a Tafel slope of 38.1 mV dec-1 . In addition, NF@NiFe-LDH-1.5-4 as an overall water splitting electrocatalyst can stably achieve a large current density of 200 mA cm-2 over 300 h at a low cell voltage of 1.83 V, meeting the requirement of industrial hydrogen production. This exceedingly simple and ultrafast synthesis of low-cost and highly active large-current-density OER electrocatalysts can propel the commercialization of hydrogen producing technology via water splitting.

Comprehensive parametric investigation of methane reforming and hydrogen separation using a CFD model

Steam-methane reforming is the primary method for industrial hydrogen production. High energy consumption and elevated greenhouse gas (GHG) emissions call for a significant improvement in the reforming process for optimum methane conversion and hydrogen production. Enhanced fuel conversion also produces more CO2 than CO, making the carbon capture process easier, consequently reducing harmful emissions. In this work, a membrane-integrated reformer reactor (MRR) has been investigated through an experimentally validated computational fluid dynamics (CFD) model using ANSYS-Fluent. The MRR model constitutes of Ni-based catalyst filled reforming zone, Pd-based hydrogen-selective membrane, and permeate zone for hydrogen recovery. The developed model has been examined for several parameters including steam-to-methane ratio, flow rate, sweeping conditions, flow direction, reformer pressure and membrane length. The results indicated a substantial increase in methane conversion with a higher steam-to-carbon (S/C) ratio for a given feed flow rate. The methane conversion increased from 34% to 63% when the S/C ratio is increased from 2 to 6 at a methane mass flow rate of 0.0018 kg/s. The results also indicate an increase in hydrogen recovery with the decrease in feed flow rate for a fixed steam-to-methane ratio. Hydrogen recovery decreased from 28% to 2% when the mass flow rate of methane is increased from 5 × 10-5 kg/s to 1.8 × 10-3 kg/s, at a fixed S/C of 4. The incorporation of sweeping steam demonstrated a significant improvement in hydrogen recovery increasing from 15% to 33% with a sweep flow rate equal to the feed flow rate and methane mass flow rate of 1.8 × 10-4 kg/s. Further increase in sweep flow rate showed very small increase in hydrogen recovery, therefore in order to minimize the use of sweeping steam, a sweeping steam flow rate equal to the feed flow rate is suggested. Furthermore, flow direction, reformer pressure and membrane length were also found to play vital role in MRR performance.

Amorphous FeNiNbPC nanoprous structure for efficient and stable electrochemical oxygen evolution

The oxygen evolution reaction (OER) is a crucial process for water splitting. Reducing overpotential is a great challenge because of four electrons transfer and slow kinetics compared to the hydrogen evolution reaction (HER). Highly efficient and stable OER catalyst with low-cost is important for industrial hydrogen production by water splitting. Here we report a simple approach to synthesize free-standing amorphous FexNi77-xNb3P13C7 with the nanoporous structure through electrochemical dealloying. The np-Fe50Ni27Nb3P13C7 exhibits remarkable OER catalytic activity with a low overpotential of 248 mV to achieve the current density of 10 mA cm−2 in 6 M KOH solution. Also, the np-Fe50Ni27Nb3P13C7 exhibits good long-term stability. The improved OER property is due to bimetallic synergy, decreased resistance of charge transfer, nanoporous structure, amorphous nature, and the generation of NiOOH during the OER process. The free-standing amorphous catalysts with nanoporous structure via electrodealloying method provide a promising approach to boost the performance of non-noble metal OER catalysts for the applications.

Self‐Supported Electrocatalysts for Practical Water Electrolysis (Adv. Energy Mater. 39/2021)

Industrial Hydrogen Production In article number 2102074, Hongyuan Yang, Matthias Driess, and Prashanth W. Menezes comprehensively discuss the design and fabrication strategy for self-supported electrocatalysts with an aim of water electrolysis for industrial hydrogen production. The most promising electrocatalysts are further overviewed from the aspects of all-pH electrolyte capacity, seawater electrolysis, overall water splitting, large current density, and long-term durability along with a brief and concise perspective.

Floc-like CNTs jointed with BixFe1−xVO4 nanoparticles for high efficient and stable photoelectrochemical seawater splitting

Photoelectrochemical (PEC) seawater splitting is an important strategy of green industrial hydrogen production on the basis of protecting fresh water resources. In this work, a floc-like BixFe1−xVO4 @CNT hetero-nanostructure (HNS) was fabricated as the building blocks of PEC anode and demonstrated a highly enhanced PEC efficiency and stability in seawater. In BixFe1−xVO4 @CNT HNS, amorphous Fe mixed BixFe1−xVO4 nanoparticles (NPs) were served for visible-light absorption, photoelectric conversion, and especially conjunct nodes of carbon nanotubes (CNTs); while CNTs were employed as the high-speed channels for carrier transfer, suppressing electron-hole recombination and leading to a highly improved PEC efficiency. As a result, the as-fabricated floc-like photoanode achieves an applicable PEC photocurrent density of 0.1 mA/cm2 at 1.5 V versus Ag/AgCl in seawater, which demonstrates the promising potential of the floc-like BixFe1−xVO4 @CNT HNS in future photoconversion applications.

Biogas upgrading using ionic liquid [Bmim][PF6] followed by thermal-plasma-assisted renewable hydrogen and solid carbon production

The use of hydrogen as clean energy has attracted significant attention because conventional industrial hydrogen production processes show negative environmental impact, require intensive energy, and/or are dependent on natural gas. The main objective of this study is to develop an innovative and environment-friendly hydrogen production process utilizing biogas as an alternative to natural gas. Ionic liquid [Bmim][PF6] shows high potential for the replacement of aqueous amine solutions for CO2 absorption and are employed for biogas upgrading, while thermal plasma (TP), which is beneficial for converting electrical energy to chemical energy, is employed for the simultaneous production of clean “turquoise” hydrogen and solid carbon. In addition, an intercooler is used to improve CO2 removal in the absorber. Heat and power integration are employed to enhance the performance of the upgrading process and thermal-plasma-assisted hydrogen production. All simulations were conducted using Aspen Plus V10.0 software. The simulated results show that the solid carbon production from biomethane increases compared to that in the proposed base case. The savings in both the heater used to preheat the TP reactor and the third flash drum are 100%, while the saving in power consumption in the compression section is 62.0%. Furthermore, sensitivity is investigated to determine the effect of biomethane composition on the performance of the proposed configuration.

Wind-powered 250 kW electrolyzer for dynamic hydrogen production: A pilot study

Alkaline water electrolysis is the most promising approach for the industrial production of green hydrogen. This study investigates the dynamic operational characteristics of an industrial-scale alkaline electrolyzer with a rated hydrogen production of 50 m3/h. Strategies for system control and equipment improvement in dynamic-mode alkaline electrolytic hydrogen production are discussed. The electrolyzer can operate over a 30%–100% rated power load, thereby facilitating high-purity (>99.5%) H2 production, competitive DC energy efficiency (4.01–4.51 kW h/Nm3 H2, i.e., 73.1%–65.0% LHV), and good gas–liquid fluid balance. A safe H2 content of 2% in O2 (50% LFL) can be guaranteed by adjusting the system pressure. In transient operation, the electrolyzer can realize minute-level power and pressure modulation with high accuracy. The results confirm that the proposed alkaline electrolyzer can absorb highly fluctuating energy output from renewables because of its capability to operate in a dynamic mode.

Self-Supported Ceramic Electrode of 1T-2H MoS2 Grown on the TiC Membrane for Hydrogen Production

Binder-free, cost-effective, and stable hydrogen evolution reaction electrocatalytic electrodes with a customized size are urgently needed for large-scale industrial hydrogen production. Toward this challenge, self-supported TiC@MoS2 (TCMS) ceramic membrane electrodes were fabricated by a self-template strategy. Porous TiC ceramic membranes with straight finger-like pores were first fabricated by phase inversion tape-casting and sintering. Then, a 1T-2H MoS2 nanosheet layer grew on the porous conductive TiC skeleton. The high conductivity of the TCMS skeleton promotes charge transfer, while the porous structure, which consists of abundant finger-like and cavernous pores, favors proton transfer and bubble transfer during the electrolysis process. The optimal TCMS composition displayed an overpotential of −127 mV at −10 mA·cm–2, a Tafel slope of 41 mV·dec–1, and an extremely high electrochemical active area of 1079.4 mF·cm–2 as well as remarkable stability in 0.5 M H2SO4. A high Faradaic efficiency of 99.7% was also achieved. The superior electrocatalytic performance was ascribed to the synergistic effect of the tight bonding and the crystal matching between TiC and MoS2, the unique dual pore structure, the abundant exposed active sites of MoS2 nanoflakes, and the high 1T-MoS2 content. First-principles density functional calculations showed that the 1T-MoS2/TiC hybrid has the lowest free energy for H adsorption (0.116 eV) and the highest density of states near the Fermi level, which leads to a strong catalytic activity.

Setting Thresholds to Define Indifferences and Preferences in PROMETHEE for Life Cycle Sustainability Assessment of European Hydrogen Production

The Life Cycle Sustainability Assessment (LCSA) is a proven method for sustainability assessment. However, the interpretation phase of an LCSA is challenging because many different single results are obtained. Additionally, performing a Multi-Criteria Decision Analysis (MCDA) is one way—not only for LCSA—to gain clarity about how to interpret the results. One common form of MCDAs are outranking methods. For these type of methods it becomes of utmost importance to clarify when results become preferable. Thus, thresholds are commonly used to prevent decisions based on results that are actually indifferent between the analyzed options. In this paper, a new approach is presented to identify and quantify such thresholds for Preference Ranking Organization METHod for Enrichment Evaluation (PROMETHEE) based on uncertainty of Life Cycle Impact Assessment (LCIA) methods. Common thresholds and this new approach are discussed using a case study on finding a preferred location for sustainable industrial hydrogen production, comparing three locations in European countries. The single LCSA results indicated different preferences for the environmental, economic and social assessment. The application of PROMETHEE helped to find a clear solution. The comparison of the newly-specified thresholds based on LCIA uncertainty with default thresholds provided important insights of how to interpret the LCSA results regarding industrial hydrogen production.

Opportunities for the development of hydrogen energy in the Murmansk region

THE PURPOSE. To analyze the perspectives for the development of hydrogen energy in the Murmansk region. To consider the possibility of implementing projects for producing "green" hydrogen for industrial using. METHODS. The method of analysis of literature sources in the field of hydrogen energy was used, as well as the method of generalizing the information obtained. RESULTS. The article describes the relevance of the topic, studies the global trend towards the transition to "green" energy. The methods of producing hydrogen are considered. The most environmentally friendly and efficient method for the production of industrial hydrogen has been identified, and possible sources of its production have been considered. CONCLUSION. As a result of the analysis of the prospects for the development of hydrogen energy in the Murmansk region, the prerequisites for the production of "green" hydrogen on an industrial scale are revealed. Possible sources for its production are listed. The article provides an example of the implementation of a project to create an international scientific research station on the territory of the Murmansk region, where hydrogen fuel cells will be used.

Simultaneously Efficient Solar Light Harvesting and Charge Transfer of Hollow Octahedral Cu2S/CdS p\u2013n Heterostructures for Remarkable Photocatalytic Hydrogen Generation

Solar-driven water splitting is a promising alternative to industrial hydrogen production. This study reports an elaborate design and synthesis of the integration of cadmium sulfide (CdS) quantum dots and cuprous sulfide (Cu2S) nanosheets as three-dimensional (3D) hollow octahedral Cu2S/CdS p–n heterostructured architectures by a versatile template and one-pot sulfidation strategy. 3D hierarchical hollow nanostructures can strengthen multiple reflections of solar light and provide a large specific surface area and abundant reaction sites for photocatalytic water splitting. Owing to the construction of the p–n heterostructure as an ideal catalytic model with highly matched band alignment at Cu2S/CdS interfaces, the emerging internal electric field can facilitate the space separation and transfer of photoexcited charges between CdS and Cu2S and also enhance charge dynamics and prolong charge lifetimes. Notably, the unique hollow Cu2S/CdS architectures deliver a largely enhanced visible-light-driven hydrogen generation rate of 4.76 mmol/(g·h), which is nearly 8.5 and 476 times larger than that of pristine CdS and Cu2S catalysts, respectively. This work not only paves the way for the rational design and fabrication of hollow photocatalysts but also clarifies the crucial role of unique heterostructure in photocatalysis for solar energy conversion.

Methane steam reforming with axial variable diameter particle structures in grille-sphere composite packed bed: A numerical study of hydrogen production performance

Methane steam reforming with packed bed is an important approach to get hydrogen in industrial production. Compared with the conventional packed bed, the grille-sphere composite packed bed has the advantages of lowering the pressure drop, increasing the uniformity of the radial temperature distribution and improving overall efficiency. In the present paper, the axial variable diameter particle structure of grille-sphere composite packed bed has been proposed, and four different structures are studied to compare their performances. Moreover, two simulation methods are used in study: (a) the solid particle method which can show details of the simulation, (b) the equivalent medium method which can show the macro situation of simulation. Through these two methods, performances of four structures in different parameters are compared and analyzed. It is found that the axial variable diameter particle structures have better performance than the typical structures in different parameters cases. Inlet temperature, inlet velocity and inlet steam-carbon ratio are set to parameters respectively in simulation. According to the simulations, higher inlet temperature and inlet steam-carbon ratio will facilitate the reactions, however, higher inlet velocity will hinder the reactions. Through the solid particle method, the reasons of better performance have been found, and two methods difference are also studied. Compared with typical structures, the specific axial variable diameter structure brings 4.5% higher outlet hydrogen mass flow and 5.2% higher outlet hydrogen selectivity. Analysis of this study can guide the design of packed beds in industrial production and the results of this study have significance in industrial hydrogen production.

Water-Gas Shift Reaction Produces Formate at Extreme Pressures and Temperatures in Deep Earth Fluids.

The water-gas shift reaction is one of the most important reactions in industrial hydrogen production and plays a key role in Fischer-Tropsch-type synthesis, which is widely believed to generate hydrocarbons in the deep carbon cycle but is little known at extreme pressure-temperature conditions found in the Earth's upper mantle. Here, we performed extensive ab initio molecular dynamics simulations and free energy calculations to study the water-gas shift reaction. We found the direct formation of formic acid from CO and supercritical water at 10-13 GPa and 1400 K without any catalyst. Contrary to the common assumption that formic acid or formate is an intermediate product, we found that HCOOH is thermodynamically more stable than the products of the water-gas shift reaction above 3 GPa and at 1000-1400 K. Our study suggests that the water-gas shift reaction may not happen in the Earth's upper mantle, and formic acid or formate may be an important carbon carrier in reducing environments, participating in many geochemical processes in deep Earth.

Industrial hydrogen production technology and development status in China: a review

This paper reviews the status of the research on industrial hydrogen production technology and development in China. The pros and cons of different hydrogen production technologies are compared. In addition, it is also conducted a comprehensive analysis of hydrogen production technology from economic and environmental aspects. Finally, the opportunities and challenges faced by the development of China’s hydrogen production technology are analyzed. In China, hydrogen production technology from fossil fuels such as coal and natural gas is relatively mature. Among them, hydrogen production by coal gasification and/or methane steam reforming have achieved large-scale applications. But its biggest problem is large carbon emissions, which does not meet China’s the development plan of "peaking carbon dioxide emissions and carbon neutrality." Hydrogen production technology through water electrolysis has many advantages, such as cleanness, pollution-free, and high purity of the hydrogen. However, it has the disadvantages of large power consumption and high hydrogen production cost. China has abundant renewable resources, but the technology for hydrogen production from renewable energy is still in its infancy and its development is not yet mature. Through comprehensive analysis, we believe that China should continue to develop new technologies while maintaining the advantages of traditional fossil fuel hydrogen production technologies. At the same time, China should also make full use of China’s remaining wind, light, electricity and biomass resources to develop green hydrogen production technologies such as electrohydrolysis. Through the above-mentioned various measures, it will effectively promote the transformation of China’s energy structure and realize the diversification of the hydrogen industry in the true sense.

One-dimensional, space-confined, solid-phase growth of the Cu9S5@MoS2 core–shell heterostructure for electrocatalytic hydrogen evolution

Binary transition metal chalcogenide core–shell nanocrystals are considered the most promising nonprecious metal catalysts for large-scale industrial hydrogen production. Herein, we report a one-dimensional, space-confined, solid-phase strategy for the growth of a Cu9S5@MoS2 core–shell heterostructure by combining electrospinning and chemical vapor deposition methods. The Cu9S5@MoS2 core–shell nanocrystals were synthesized in situ on carbon nanofibers (Cu9S5@MoS2/CNFs) by an S vapor graphitization process. Tuning of the MoS2 shell numbers can be controlled by changing the mass ratio of the Cu and Mo precursors. We experimentally determined the effects of the thickness of the MoS2 shell on the electrocatalytic activity for the hydrogen evolution reaction (HER) in acidic and alkaline solutions. When the mass ratio is 3:1, the Cu9S5@MoS2/CNFs show the fewest MoS2 shells with just 1–2 layers each and exhibit the best HER performance with small overpotentials of 116 mV and 114 mV in acidic and alkaline solutions, respectively, at a current density of 10 mA cm−2. The core shell structures, with their unique Cu-S-Mo nanointerfaces, could enhance the electron transfer and surface area, thus increasing the performance of the HER. This work provides a facile method to design unique core shell assemblies in one-dimensional nanostructures.

TM LDH Meets Birnessite: A 2D‐2D Hybrid Catalyst with Long‐Term Stability for Water Oxidation at Industrial Operating Conditions

AbstractEfficient noble‐metal free electrocatalyst for oxygen evolution reaction (OER) is critical for large‐scale hydrogen production via water splitting. Inspired by Nature's oxygen evolution cluster in photosystem II and the highly efficient artificial OER catalyst of NiFe layered double hydroxide (LDH), we designed an electrostatic 2D‐2D assembly route and successfully synthesized a 2D LDH(+)‐Birnessite(−) hybrid. The as‐constructed LDH(+)‐Birnessite(−) hybrid catalyst showed advanced catalytic activity and excellent stability towards OER under a close to industrial hydrogen production condition (85 °C and 6 M KOH) for more than 20 h at the current densities larger than 100 mA cm−2. Experimentally, we found that besides the enlarged interlayer distance, the flexible interlayer NiFe LDH(+) also modulates the electronic structure of layered MnO2, and creates an electric field between NiFe LDH(+) and Birnessite(−), wherein OER occurs with a greatly decreased overpotential. DFT calculations confirmed the interlayer LDH modulations of the OER process, attributable to the distinct electronic distributions and environments. Upshifting the Fe‐3d orbitals in LDH promotes electron transfer from the layered MnO2 to LDH, significantly boosting up the OER performance. This work opens a new way to fabricate highly efficient OER catalyst for industrial water oxidation.

TM LDH Meets Birnessite: A 2D-2D Hybrid Catalyst with Long-Term Stability for Water Oxidation at Industrial Operating Conditions.

Efficient noble-metal free electrocatalyst for oxygen evolution reaction (OER) is critical for large-scale hydrogen production via water splitting. Inspired by Nature's oxygen evolution cluster in photosystem II and the highly efficient artificial OER catalyst of NiFe layered double hydroxide (LDH), we designed an electrostatic 2D-2D assembly route and successfully synthesized a 2D LDH(+)-Birnessite(-) hybrid. The as-constructed LDH(+)-Birnessite(-) hybrid catalyst showed advanced catalytic activity and excellent stability towards OER under a close to industrial hydrogen production condition (85 °C and 6 M KOH) for more than 20 h at the current densities larger than 100 mA cm-2 . Experimentally, we found that besides the enlarged interlayer distance, the flexible interlayer NiFe LDH(+) also modulates the electronic structure of layered MnO2 , and creates an electric field between NiFe LDH(+) and Birnessite(-), wherein OER occurs with a greatly decreased overpotential. DFT calculations confirmed the interlayer LDH modulations of the OER process, attributable to the distinct electronic distributions and environments. Upshifting the Fe-3d orbitals in LDH promotes electron transfer from the layered MnO2 to LDH, significantly boosting up the OER performance. This work opens a new way to fabricate highly efficient OER catalyst for industrial water oxidation.