Water Electrolysis For Hydrogen Production Research Articles

Self-sacrificing and self-supporting biomass carbon anode–assisted water electrolysis for low-cost hydrogen production

Electrooxidation of renewable and CO2-neutral biomass for low-cost hydrogen production is a promising and green technology. Various biomass platform molecules (BPMs) oxidation assisted hydrogen production technologies have obtained noticeable progress. However, BPMs anodic oxidation is highly dependent on electrocatalysts, and the oxidation mechanism is ambiguous. Meanwhile, the complexity and insolubility of natural biomass severely constrain the efficient utilization of biomass resources. Here, we develop a self-sacrificing and self-supporting carbon anode (SSCA) using waste corncobs. The combined results from multiple characterizations reveal that the structure-property-activity relationship of SSCA in carbon oxidation reaction (COR). Theoretical calculations demonstrate that carbon atoms with a high spin density play a pivotal role in reducing the adsorption energy of the reactive oxygen intermediate (*OH) during the transition from OH- to *OH, thereby promoting COR. Additionally, the HER||COR system allows driving a current density of 400 [Formula: see text] at 1.24 V at 80 °C, with a hydrogen production electric consumption of 2.96 kWh Nm-3 (H2). The strategy provides a ground-breaking perspective on the large-scale utilization of biomass and low-energy water electrolysis for hydrogen production.

3D NiCoW Metallic Compound Nano-Network Structure Catalytic Material for Urea Oxidation

Urea shows promise as an alternative substrate to water oxidation in electrolyzers, and replacing OER with the Urea Oxidation Reaction (UOR, theoretical potential of 0.37 V vs. RHE) can significantly increase hydrogen production efficiency. Additionally, the decomposition of urea can help reduce environmental pollution. This paper improves the inherent activity of catalytic materials through morphology and electronic modulation by incorporating tungsten (W), which accelerates electron transfer, enhances the electronic structure of neighboring atoms to create a synergistic effect, and regulates the adsorption process of active sites and intermediates. NiCoW catalytic materials with an ultra-thin nanosheet structure were prepared using an ultrasonic-assisted NaBH4 reduction method. The results show that during the OER process, NiCoW catalytic materials have a potential of only 1.53 V at a current density of 10 mA/cm2, while the UOR process under the same conditions requires a lower potential of 1.31 V, demonstrating superior catalytic performance. In a mixed electrolyte of 1 M KOH and 0.5 M urea, overall water splitting also shows excellent performance. Therefore, the designed NiCoW electrocatalyst, with its high catalytic activity, provides valuable insights for enhancing the efficiency of water electrolysis for hydrogen production and holds practical research significance.

N-doped porous graphite with multilevel pore defects and ultra-high conductivity anchoring Pt nanoparticles for proton exchange membrane water electrolyzers

Water electrolysis for hydrogen production offers a promising solution to future energy crises and environmental challenges. Although platinum is an efficient catalyst for hydrogen evolution reactions (HERs), its high cost and stability challenges limit its widespread use. A novel platinum-based catalyst, comprising platinum nanoparticles on nitrogen-doped porous graphite (Pt-N-porous graphite), addresses these limitations. This catalyst prevents nanoparticle aggregation, provides a high specific surface area of 1308 m2 g−1, and enhances mass transfer and active site exposure. Additionally, it exhibits superior electrical conductivity compared to commercial Pt-C, enhancing charge transfer efficiency. The Pt-N-porous graphite catalyst achieves an overpotential of 99 mV at 100 mA cm−2 and maintains stable performance after 10000 cycles. Applied as a catalyst-coated membrane (CCM) in a proton exchange membrane (PEM) electrolyzer, it demonstrates excellent performance. Thus, the industrially synthesizable Pt-N-porous graphite catalyst holds great potential for large-scale energy applications.

Fe(III)-cycle enhanced carbon oxidation reaction for low-energy hydrogen production via water electrolysis

Integrating the hydrogen evolution reaction (HER) with the carbon oxidation reaction (COR) is a promising method for producing H₂ with lower energy consumption. However, due to the passivation effect of oxygen functional groups (OFGs) for COR and Fe³⁺, achieving efficient and sustainable carbon oxidation to assist water electrolysis for hydrogen production remains a challenge over the past decades. This study introduced [EDTA·Fe(III)]– as a mediator to promote COR. [EDTA·Fe(III)]– effectively prevented the oxidation layer on the carbon surface from anchoring Fe (III) and reactivated the carbon that had been passivated by the oxidation layer. Density functional theory calculations indicated that the notable COR activity resulted from [EDTA·Fe(III)]– effectively lowering the vertical ionization potential of carbon, without being affected by OFGs. Notably, in the HER||COR-[EDTA·Fe(III)]– system, a cell voltage of merely 0.74 V is sufficient to reach a current density of 10 mA cm−2, with the corresponding energy consumption being 1.76 kWh Nm−3 (H2). This strategy offers new insights into achieving stable, low-energy hydrogen production via water electrolysis.

Mini-Review of Advancements and Prospects in Coal-Assisted Water Electrolysis for Hydrogen Production

Mini-Review of Advancements and Prospects in Coal-Assisted Water Electrolysis for Hydrogen Production

Techno economic analysis of electrolytic hydrogen production by alkaline and PEM electrolysers using MCDM methods

Hydrogen, a crucial clean and renewable energy source, addresses pressing challenges of energy security and environmental pollution. Water electrolysis for hydrogen production is a promising approach to satisfy the growing demand for sustainable energy. This study uniquely performs a comprehensive techno-economic analysis of hydrogen production using both Alkaline and Proton Exchange Membrane (PEM) electrolyzers, a first in the field to evaluate their performance comprehensively with advanced Multi-Criteria Decision-Making (MCDM) techniques. Leveraging TOPSIS, WASPAS interval methods, and the Best Worst Method (BWM) with fuzzy logic, this research introduces a novel evaluation framework that incorporates a wide-ranging set of factors, including environmental, technical, technological, economic, and social aspects, divided into 30 sub-criteria. These insights offer a comprehensive understanding of each electrolyser's strengths and weaknesses, helping stakeholders make informed decisions about cost reduction in hydrogen production technologies. This has not been done before. Although cost results favour Alkaline electrolysers, PEM electrolysers are attractive for specific applications where their benefits justify the higher initial cost, choosing between Alkaline and PEM electrolysers dependent on a given hydrogen production project's requirements.

Research Progress in Structure Evolution and Durability Modulation of Ir- and Ru-Based OER Catalysts under Acidic Conditions.

Green hydrogen energy, as one of the most promising energy carriers, plays a crucial role in addressing energy and environmental issues. Oxygen evolution reaction catalysts, as the key to water electrolysis hydrogen production technology, have been subject to durability constraints, preventing large-scale commercial development. Under the high current density and harsh acid-base electrolyte conditions of the water electrolysis reaction, the active metals in the catalysts are easily converted into high-valent soluble species to dissolve, leading to poor structural durability of the catalysts. There is an urgent need to overcome the durability challenges under acidic conditions and develop electrocatalysts with both high catalytic activity and high durability. In this review, the latest research results are analyzed in depth from both thermodynamic and kinetic perspectives. First, a comprehensive summary of the structural deactivation state process of noble metal oxide catalysts is presented. Second, the evolution of the structure of catalysts possessing high durability is discussed. Finally, four new strategies for the preparation of stable catalysts, "electron buffer (ECB) strategy", combination strength control, strain control, and surface coating, are summarized. The challenges and prospects are also elaborated for the future synthesis of more effective Ru/Ir-based catalysts and boost their future application.

Controllable synthesis of Pt-rich shell/Mx core [M = Ni, Fe, Co] metal aerogels as efficient electrocatalysts for hydrogen evolution reaction

Water electrolysis for hydrogen production offers a solution to the fossil fuel crisis, relying heavily on electrocatalysts for the hydrogen evolution reaction (HER). Fortunately, metal aerogels (MAs) with three-dimensional network structures reveal great potential as HER electrocatalysts. However, their simple synthesis and widespread application still present significant challenges. Here, PtNix MAs electrocatalysts, by controlling the Ni/Pt feeding ratio and using NaBH4 reduction, are prepared via a simple one-step method. Notably, PtNi4 MAs with Pt-rich shell/Ni core structure exhibit excellent HER property, showing a low overpotential of 16.3 mV at 10 mA cm−2 and a mass activity density of 2.28 A mgPt-1 at 70 mV. The outstanding HER properties of PtNi4 MAs are ascribed to the synergistic catalytic effect of Pt and Ni, the core–shell structure of the sample, and the abundant three-dimensional network porosity. Density functional theory (DFT) demonstrates that PtNi4 MAs’ core–shell structure have the lowest dissociation energy of H2O and ΔGH* on the catalyst surface. Furthermore, the replacement of non-precious metal (Ni/Fe/Co) does not affect the formation of the Pt-rich shell structure. Opposite the substitution of reducing agent species affects the formation of Pt-rich shell structure. This work can offer valuable insights for the future sustainable energy applications of MAs materials.

Bifunctional heterostructured nitrogen-doped carbon-layer-loaded NiSe2-FeSe2 electrocatalyst for efficient water splitting

Developing high-performance, eco-friendly bifunctional electrocatalysts is crucial to popularizing water electrolysis for hydrogen production, but it still presents major challenges. Here, we develop a composite material with NiSe2-FeSe2 heterostructure loaded on N-doped carbon layers by utilizing the metal-organic framework as a sacrificial template (NiSe2-FeSe2/NC). According to microstructural studies, direct contact between NiSe2 and FeSe2 induces charge transfer and enhances conductivity, while sensible arraying of NiSe2-FeSe2/NC nanosheets fully exposes active sites and protects catalysts from violent reaction processes. The NiSe2-FeSe2/NC heterostructured catalysts show excellent bifunctional catalytic activity for hydrogen and oxygen evolution reactions, with overpotentials of 54 and 232 mV at 10 mA cm−2, respectively. Moreover, NiSe2-FeSe2/NC also retains superiority in a two-electrode system, needing lower voltage to drive the overall water splitting at 10 mA cm−2 (1.53 V) than Pt/C||RuO2 as well as long-term stability. This work introduces a novel concept for developing state-of-the-art non-noble metal catalysts for hydrogen production and new insights into interface engineering.

Research on performance optimization of electrolytic cell: Non-parameter topology and parameter optimization

The technology of water electrolysis for hydrogen production converts renewable energy into hydrogen, enabling efficient storage and utilization of clean energy. The key to enabling the large-scale development of water electrolysis technology lies in enhancing the performance of electrolytic cells and minimizing energy consumption. The mastoid process structure obviously influences the electrolytic cell's flow and electrochemical performance. Therefore, this paper studied the sensitivity of the mastoid process structure to the optimization target, designed the shape topology and the parameter optimization structure, and further analyzed the influence of the two optimization methods on the flow and electrochemical performance of the electrolytic cell based on the multi-physics coupling model. The results show that under the same deformation area, the pressure drop of the topology and the parameter optimization structure is reduced by 17.17 % and 11.89 % compared with that of the original structure. The electrochemical properties were almost unaffected, and the change value was less than 0.1 %. Topology optimization design can achieve optimal performance within limited deformation constraints, and parameter optimization design is more conducive to industrial processing.

Black etched electroless Ni–P coatings for enhanced efficiency towards alkaline water splitting

Requirements for wider use of water electrolysis for hydrogen production include the development of highly efficient, cheap, and easily made electrodes. Promising properties can be achieved with Ni–P materials. Herein, nitric acid etching (being used for blackening of electroless Ni–P coatings) resulted in enhanced efficiency towards hydrogen and oxygen evolution reactions (HER and OER) in 1.0 M KOH. For etched Ni-7.6 wt%P coating, the potential of HER at −10 mA cm−2 was about −0.20 V vs. RHE, and the potential of OER at 10 mA cm−2 was about 1.67 V, whereas for etched Ni they were −0.40 V and 1.94 V, respectively. Surface layers of etched coatings contained bundles of microrods and were enriched in O and P. Impedance measurements showed that etching caused about a 60-fold increase of CPE which can be ascribed to the development of surface area and pseudocapacitance of redox reactions, involving Ni ⇄ NiO. It is proposed that the electroactivity of Ni–NiO composite is to a large extent associated with the oxide reduction effects, involving high activity of newborn (pristine) Ni nanoparticles, acidification at the metal surface and disclosure of bare metal. Etched Ni–P coatings can be promising for the activation of electrodes for water electrolysis.

Effect of porous irregular ZrO2 nanoparticles on the performance of alkaline water electrolysis composite separator membranes under complex conditions

Developing composite separator membranes with low area resistance, high bubble point pressure, and long-term safety and stability is crucial for alkaline water electrolysis for hydrogen production as a key component of electrolyzer systems. In this study, PPS mesh fabric reinforced PSF@ZrO2 composite separator membranes were successfully prepared using the immersion-drawing phase inversion method, with PSF as the alkali-resistant polymer matrix and porous irregular ZrO2 nanoparticles as the hydrophilic additive. The experimental results showed that replacing commercial ZrO2 with porous irregular ZrO2 nanoparticles at an 85 wt% ZrO2 nanoparticle loading improved both bubble point pressure and current transmission efficiency, attributed to the change in the morphological structure of the ZrO2 nanoparticles. The P-Z85 composite separator membrane exhibited highly promising characteristics, with a high bubble point pressure of 3.76 bar and a low area resistance of 0.20 Ω cm2. Stability tests conducted in 30 wt% KOH electrolyte at 80 °C and a current density of 0.65 A cm−2 demonstrated excellent continuous electrolysis stability for the P-Z85 composite separator membrane. These results indicate that the PSF@ZrO2/PPS composite separator membrane prepared in this study exhibits excellent performance in 30 wt% KOH electrolyte, significantly extending its service life.

Scaling Up Stability: Navigating from Lab Insights to Robust Oxygen Evolution Electrocatalysts for Industrial Water Electrolysis

AbstractIn the pursuit of sustainable hydrogen production via water electrolysis, paramount importance of electrocatalyst stability emerges as a defining factor for long‐term industrial viability. A thorough understanding and enhancement of stability not only ensure extended catalyst lifetimes but also pave the way for consistent and efficient hydrogen generation. This review focuses on the pivotal role of stability in determining the practical viability of oxygen evolution electrocatalysts (OECs) for large‐scale applications in water electrolysis for hydrogen production. The paper explores the pivotal role of stability over initial activity, citing examples and hypothetical scenarios. First, figures of merits for stability evaluation of the electrocatalyst are explained along with the available benchmarking protocols for stability evaluation. Further, the text delves into various strategies that can enhance the stability of the electrocatalyst which include self‐healing/regeneration pathway, oxygen evolution reaction (OER) mechanism optimization to achieve highly stable OER and stabilization of active metals atoms within the electrocatalyst to inhibit dissolution as a way forward for industrial application. The interplay of stability, activity, and cost is also explained to suit the industrial application of the electrocatalyst. Lastly, it outlines challenges, prospects, and future directions, presenting a guide for advancing OECs in the hydrogen generation landscape.

Advances in green hydrogen generation based on MoSe2 hybrid catalysts

Green hydrogen production technology is of great significance in realizing energy transition and combating climate change. Recently, with the rapid development of nanomaterials and catalytic technology, transition metal dichalcogenides represented by MoSe2 have attracted wide attention in the field of hydrogen production. This review comprehensively reviewed the applications and recent progress of MoSe2 in green hydrogen production in terms of photocatalytic water splitting for hydrogen production, water electrolysis and methanol-assisted water electrolysis for hydrogen production. The active site and electronic structure-related optimization of MoSe2 was also carried out through various optimization strategies to improve its green hydrogen production efficiency. The challenges and perspectives of MoSe2 hybrid catalysts were also concluded. This review showed a comprehensive overview of MoSe2 hybrid catalysts by summarizing the optimization strategies for catalyst property modification and their application in hydrogen production, which would be helpful for relevant progress understanding.

M (M=Mn, Fe, and Cu)-doped Ni3S2@Co9S8 grown on Ni foam with different heterostructures as catalysts for overall seawater splitting

The increasing global energy demand and the environmental impact of fossil fuels have prompted scientists to seek clean and renewable energy solutions. Hydrogen energy, known for its efficiency and environmental benefits, is considered an ideal choice. Given the limited availability of freshwater resources, this study uses abundant seawater as the feedstock for water electrolysis. Our research focuses on developing non-precious metal electrocatalysts to enhance the efficiency and economic viability of water electrolysis for hydrogen production. Using Ni3S2@Co9S8 as the base material, we regulate the catalytic performance by doping with transition metals such as Mn, Fe, and Cu. The Mn-Ni3S2@Co9S8/NF electrode exhibits excellent hydrogen evolution reaction (HER) (overpotential of 76 mV @10 mA cm−2) and oxygen evolution reaction (OER) (overpotential of 261 mV @10 mA cm−2) activity in seawater electrolytes, significantly reducing the overpotential requirements. Density Functional Theory (DFT) assessments reveal that Co9S8 possesses optimal gibbs free energy capabilities and Mn-Ni3S2 possesses more electron distribution, explaining its high catalytic efficiency. This study provides an in-depth analysis of the catalyst structure and performance, offering valuable insights for developing efficient and stable electrocatalysts for water electrolysis, thereby contributing to the sustainable development of the hydrogen economy and advancements in clean energy technology.

Techno economic and life cycle assessment of olefin production through CO2 hydrogenation within the power-to-X concept

The paper deals with exhaustive process modelling, techno-economic and life cycle assessment (TEA/LCA) of olefin (ethylene and propylene) production through captured CO2 and electrolytic hydrogen. Olefins are important building block chemicals with several applications and carbon capture and utilisation (CCU) can provide a sustainable production route. The proposed system involves direct air capture (DAC) of CO2; proton exchange membrane (PEM) water electrolysis for hydrogen production, methanol synthesis, methanol to olefins (MTO) upgrade, and power generation from off-shore wind turbines. This study proposes a new integrated process as the first attempt to holistically assess a whole CCU assembly aiming at olefins production. Processing modelling has been implemented using the Aspen plus V12.1 and MATLAB R2022a software to solve the mass and energy balances of each unit operation. The modelling results showed a carbon efficiency of 72.3% to ethylene and propylene. In addition, the process is designed and integrated in such a way that no external heat supply is required. A specific energy consumption (SEC) of 150 MJ/kg olefins (41 kWh/kg) has been estimated. A minimum selling price of £3.67 per kg of olefins is required for the proposed process to break-even. The sensitivity analysis has revealed that the major cost driver is the cost of electricity. In addition, the life cycle assessment (LCA) has exposed that the proposed synthesis route of olefins has the potential to reduce the global warming potential (GWP) by 47% compared to fossil - based production. The outcomes of this study can be beneficial to engineering conceptual studies, policy makers and contribute new information to the CCU academic community.

A novel water electrolysis hydrogen production system powered by a renewable hydrovoltaic power generator

The acceleration of eco-friendly energy generation technologies has been driven by pressing environmental issues such as global warming. Among the promising approaches is electricity generation from infinite moisture. Water evaporation-based power generation has garnered significant attention due to its capability for continuous power generation. However, existing devices face challenges in maintaining long-term generation and producing sufficient voltage and current. In this study, we introduce a cellulose sponge-based hydrovoltaic power generator (CHPG) as a power source for hydrogen production. A single CHPG (3.0 × 1.0 × 0.7 cm3) achieves an open-circuit voltage of approximately 0.47 V and a short-circuit current of approximately 477 μA under relative humidity of 45–50 % at 25 °C. To enhance water electrolysis for hydrogen production, we optimized and scaled up the CHPGs into modules (six CHPGs in series) and packages (six CHPG modules in parallel). Consequently, the generator with three packages connected in parallel produces 2.09 V and 3.11 mA. This configuration enabled hydrogen gas generation at a rate of 81.0 μmol h−1 from the electrode. This study lays the groundwork for future research aimed at hydrogen gas production through hydrovoltaic electricity.

Effects of foam cathode electrode structure on alkaline water electrolysis for hydrogen production

Hydrogen is widely recognized as a clean and sustainable energy source. One of the most promising methods for hydrogen production is alkaline water electrolysis. The efficiency and cost-effectiveness of this process heavily depend on the choice of a suitable porous electrode structure. This paper aims to investigate impact of the porous structure on the performance of alkaline electrolytic water through experiments and multi-physics field simulation. Specifically, the whole cell performance test and hydrogen-evolution reaction (HER) test of nickel foam were conducted in an electrolytic cell using 1 M KOH. Results revealed that various parameters of the electrode structure, such as specific surface area, pore density, thickness, and electronic conductivity, significantly influenced the hydrogen evolution. Increasing the specific surface area or pore density proved to enhance the hydrogen evolution under conventional voltage. Reducing the thickness has a similar effect. Additionally, materials with high conductivities increase the reaction rate. Based on experimental results, the optimal nickel foam cathode structure was 1000 μm thickness and 75 PPI pore density. The results of stability tests and electrolysis voltage efficiency analysis provide further support for the positive effect of this structure on hydrogen evolution. This study provides rational reference for designing efficient and stable porous electrode structures.

Potential for large-scale deployment of offshore wind-to-hydrogen systems in the United States

This study explores the role of producing low-carbon hydrogen using water electrolysis powered by offshore wind in facilitating the United States’ transition to a net-zero emissions economy by 2050. This research introduces an open-source scenario analysis tool for offshore wind-to-hydrogen systems, aiming to assess the impact of technology, regional considerations, and policy incentives on the cost of producing low-carbon hydrogen through offshore wind. Conducting a regional techno-economic analysis at four U.S. coastal sites, the study evaluates two energy transmission configurations and examines associated costs for the years 2025, 2030, and 2035. The results highlight that locations using fixed-bottom technology may achieve cost-competitive water electrolysis hydrogen production by 2030 through leveraging geologic hydrogen storage and federal policy incentives. Furthermore, floating technology locations are expected to see an average 38% reduction in the levelized cost of hydrogen from 2025 to 2035.

Sulfonated graphene oxide linked with alkali metal ions membranes for proton conductivity in hydrogen production from water electrolysis

Amid technological advances, rising energy demand, and environmental concerns, countries endorse green energy solutions. Prominent among them is hydrogen production via clean water electrolysis, a key strategy for sustainable development. Herein, to address the limitations of expensive and potentially harmful Nafion membranes, we have developed a new graphene oxide (GO) series membranes (hydrophilic sulfonated GO (GO-SO3H) linked with monovalent alkali metal ions were synthesized to fabricate the membranes) to be used in water electrolysis for hydrogen production by introducing the iodide oxidation reaction (IOR) as an alternative to the traditional oxygen evolution reaction (OER). Various modifications by sulfuric acid, methanol, and different alkali metal hydroxides (LiOH, NaOH, KOH) result in membranes with distinct properties. Characterization techniques, including ATR-FTIR, SEM, AFM, XRD, water contact angle (WCA), and electrochemical impedance spectroscopy (EIS), validated the modifications, assessed membrane morphology, interlayer spacing, hydrophilicity, and electrical properties. Among the membranes, GO-SO3K stood out, exhibiting the highest proton conductivity (119.16 mS) and superior potassium ion permeability (20.382 cm/s). Importantly, all GO series membranes demonstrate excellent stability in the electrochemical system. The findings suggested that GO-SO3K holds promise as a potassium ion-conductive membrane for efficient and sustainable hydrogen production, offering a viable alternative to conventional Nafion membranes in water electrolysis applications.