Large-scale Hydrogen Production Research Articles

Towards energy freedom: Exploring sustainable solutions for energy independence and self-sufficiency using integrated renewable energy-driven hydrogen system

In the pursuit of sustainable energy solutions, the integration of renewable energy sources and hydrogen technologies has emerged as a promising avenue. This paper introduces the Integrated Renewable Energy-Driven Hydrogen System as a holistic approach to achieve energy independence and self-sufficiency. Seamlessly integrating renewable energy sources, hydrogen production, storage, and utilization, this system enables diverse applications across various sectors. By harnessing solar and/or wind energy, the Integrated Renewable Energy-Driven Hydrogen System optimizes energy generation, distribution, and storage. Employing a systematic methodology, the paper thoroughly examines the advantages of this integrated system over other alternatives, emphasizing its zero greenhouse gas emissions, versatility, energy resilience, and potential for large-scale hydrogen production. Thus, the proposed system sets our study apart, offering a distinct and efficient alternative compared to conventional approaches. Recent advancements and challenges in hydrogen energy are also discussed, highlighting increasing public awareness and technological progress. Findings reveal a payback period ranging from 2.8 to 6.7 years, depending on the renewable energy configuration, emphasizing the economic attractiveness and potential return on investment. This research significantly contributes to the ongoing discourse on renewable energy integration and underscores the viability of the Integrated Renewable Energy-Driven Hydrogen System as a transformative solution for achieving energy independence. The employed model is innovative and transferable to other contexts.

Optimum pulse electrolysis for efficiency enhancement of hydrogen production by alkaline water electrolyzers

Alkaline water electrolysis is considered as the most feasible way to realize large-scale hydrogen production from renewable energy sources. However, the poor efficiency performance in low load limits the wide-range operation of alkaline water electrolyzers. The energy loss caused by the parasitic current is the main reason of the poor efficiency in low load. Based on the electrolyzer internal structure, an improved model of alkaline water electrolyzers is proposed and the inefficiency mechanism is illustrated. It is found that by applying pulse current for electrolysis, the efficiency of hydrogen production in low load can be enhanced greatly. The influence of the pulse current magnitude and duty ratio on the efficiency improvement is studied. Under different operation conditions, they can be regulated to achieve the maximum efficiency of hydrogen production. The electrolyzer parameters also affect the efficiency trend, especially the double layer capacitance. Finally, the results are experimentally verified on a 10 kW alkaline water electrolyzer.

Synergistic interfacial electronic modulation of topotactically developed bimetallic CoNiP on NiS nanorods for enhanced alkaline hydrogen evolution reaction.

Designing hybrid transition metal phosphosulfide electrocatalysts is critical for the hydrogen evolution reaction (HER). We propose a novel approach by designing a hierarchical structure of cobalt phosphide (CoP) and nickel phosphide (Ni8P3) nanoparticles topotactically developed on nickel sulfide (Ni3S2) nanorods (CoNiP/NiS) via a sulfuration-phosphorization strategy using conductive 3D nickel foam. Hierarchical heterostructured nanorods were achieved without the need for template removal steps or the assistance of surfactants. This not only simplifies the process but also improves the exposure of active sites for catalytic purposes. Furthermore, the theoretical calculation results revealed that the high H* adsorption-free energy for CoP and Ni8P3 phases significantly decreases upon coupling with Ni3S2, which indicates that the interfacial electronic interaction synergistically modulates both CoP and Ni8P3 (CoNiP) at the coupled interfaces and facilitates the adsorption and desorption of H* intermediates during the HER process. The resulting electrode exhibits excellent performance in the HER catalytic process and shows great performance for further exploration in the urea oxidation reaction (UOR). Our work provides a stepping stone toward rational topotactic transformation of active materials on porous substrates, using electronic structure regulation and heterointerfaces to produce promising electrocatalysts for sustainable, large-scale hydrogen production from water electrolysis.

In situ evolution of bulk-active γ-CoOOH with immobilized Gd dopants enabling efficient oxygen evolution electrocatalysis.

Promoting the in situ reconstruction of transition metal (TM)-based precatalysts into low-crystalline and well-modified TM (oxy)hydroxides (TMOxHy) during the alkaline oxygen evolution reaction (OER) is crucial for enhancing their catalytic performances. In this study, we incorporated gadolinium (Gd) into a cobalt hydroxide precatalyst, achieving a deep reconstruction into cobalt oxyhydroxide (γ-CoOOH) while retaining the incorporated Gd during the activation process of the alkaline OER. The unconventional non-leaching Gd dopants endow γ-CoOOH with reduced crystallinity, increasing the exposure of electrolyte-accessible Co atoms and enhancing its bulk activity. Furthermore, the modulation of the electronic structure of γ-CoOOH substantially boosts the intrinsic activity of the active Co sites. As a result, when supported on nickel foam, the catalyst exhibits remarkable alkaline OER performance, achieving a current density of 100 mA cm-2 at a low overpotential of approximately 327 mV. Notably, an ultrahigh current density of 1000 mA cm-2 is robustly maintained for 5 days, highlighting its immense potential for practical applications in large-scale hydrogen production.

Large-area all-perovskite-based coplanar photoelectrodes for scaled-up solar hydrogen production

Large-scale solar hydrogen production is enabled by the treatment of perovskite films through additive-added antisolvent bathing, achieving a solar-to-hydrogen efficiency of 9.89% and an outstanding hydrogen production of 145.56 μmol h−1 cm−2.

Interfacial electron-engineered tungsten oxynitride interconnected rhodium layer for highly efficient all-pH-value hydrogen production

Tungsten oxynitride coupled rhodium layers has been successfully synthesized by facile a sol–gel method. Owning to the unique electronic state and coordination environment of Rh, the Rh–WNO catalyst exhibits enhanced HER activity in wide pH.

Rare-metal single atom catalysts for large scale hydrogen production under actual operating conditions

The electrocatalytic hydrogen evolution reaction (HER) is an efficient technology for hydrogen production that holds great significance for the development of renewable energy economies. Rare-metal-based catalysts are considered benchmark catalysts...

Cr-doped CoFe2O4 nanorod array modified by oxygen vacancy-rich cerium oxide as an efficient bifunctional total water splitting catalyst

Highly efficient and stable bifunctional electrocatalysts for total water splitting are crucial for the realization of large-scale hydrogen production. In this study, we successfully synthesized CeOx-modified CoCryFe2-yO4 nanorod array structures...

Green reaction engineering towards an iron-based nanostructured hybrid as an electrocatalyst for oxygen evolution reaction

Developing robust electrocatalysts based on nonprecious metals with high activity in the sluggish oxygen-evolution reaction (OER) is crucial for achieving large-scale hydrogen production.

Manipulating electron redistribution between iridium and Co6Mo6C bridging with a carbon layer leads to a significantly enhanced overall water splitting performance at industrial-level current density.

Nowadays, alkaline water electrocatalysis is regarded as an economical and highly effective approach for large-scale hydrogen production. Highly active electrocatalysts functioning under large current density are urgently required for practical industrial applications. In this work, we present a meticulously designed methodology to anchor Ir nanoparticles on Co6Mo6C nanofibers (Co6Mo6C-Ir NFs) bridging with nitrogen-doped carbon as efficient bifunctional electrocatalysts with both excellent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activity and stability in alkaline media. With a low Ir content of 5.9 wt%, Co6Mo6C-Ir NFs require the overpotentials of only 348 and 316 mV at 1 A cm-2 for the HER and OER, respectively, and both maintain stability for at least 500 h at ampere-level current density. Consequently, an alkaline electrolyzer based on Co6Mo6C-Ir NFs only needs a voltage of 1.5 V to drive 10 mA cm-2 and possesses excellent durability for 500 h at 1 A cm-2. Density functional theory calculations reveal that the introduction of Ir nanoparticles is pivotal for the enhanced electrocatalytic activity of Co6Mo6C-Ir NFs. The induced interfacial electron redistribution between Ir and Co6Mo6C bridging with nitrogen-doped carbon dramatically modulates the electron structure and activates inert atoms to generate more highly active sites for electrocatalysis. Moreover, the optimized electronic structure is more conducive to the balance of the adsorption and desorption energies of reaction intermediates, thus significantly promoting the HER, OER and overall water splitting performance.

Plasma-assisted fabrication of ultra-dispersed copper oxides in and on C-rich carbon nitride as functional composites for the oxygen evolution reaction.

Significant efforts have been continuously devoted to the mastering of green catalysts for the oxygen evolution reaction (OER), whose sluggish kinetics prevents a broad market penetration of water splitting as a sustainable route for large-scale hydrogen production. In this extensive scenario, carbon nitride (CN)-based systems are in focus thanks to their favorable characteristics, and, whereas graphitic CN has been largely investigated, the potential of amorphous carbon nitride (a-CNx) systems remains almost entirely unexplored. In this regard, our study presents a novel two-step plasma-assisted route to a-CNx systems comprising ultra-dispersed, i.e. "quasi-atomic" CuxO (x = 1, 2). The target materials were fabricated using an original strategy consisting in the magnetron sputtering of a-CNx on conducting glasses at room temperature, followed by functionalization with low CuxO amounts by radio frequency (RF)-sputtering, and final annealing under an inert atmosphere. The tailoring of the CuxO co-catalyst content and spatial dispersion, as well as the overall composite features as a function of preparative conditions, enabled a direct modulation of the resulting OER performances, rationalized based on the formation of p-n CuxO/a-CNx heterojunctions. The amenable and scalable synthesis approach underscores the practicality of this method to develop (photo)electrocatalysts synergistically integrating the advantages of both constituents, yielding low-cost, green, and stable functional platforms that could contribute to the broader adoption of sustainable energy solutions.

Boosting the Oxygen Evolution Reaction via the Reconstruction of M(OH)x/Fe3O4 Catalyst

For large-scale hydrogen production from electrocatalysis of water, the Ni- and/or Fe-based catalysts were commonly used but limited by the ultrahigh overpotential and poor stability at high current density (>500...

Rapidly synthesized porous alloy heterostructure catalysts for ultra-low energy water splitting under industrial conditions.

RANEY® nickel is extensively applied in industrial settings for its low cost and ease of scale-up. Nevertheless, its poor activity and high energy consumption restrict the progress of large-scale hydrogen production. Here, we used a RANEY® nickel substrate combined with a one-step electrodeposition method to prepare porous NiFe@RN bifunctional catalysts. The results show excellent catalytic activity in both the HER and OER, with overpotentials of 93.51 and 248 mV, respectively, at a current density of 100 mA cm-2. In industrial settings, the NiFe@RN assembled dual-electrode electrolyzer requires only 1.68 V to drive a current density of 500 mA cm-2, demonstrating excellent stability for 20 hours. Simultaneously, this study also found that the synergistic effect of Ni0, Fe0, and the NiFeOOH heterostructure can significantly enhance the electrode's catalytic activity and stability. At a current density of 500 mA cm-2, the energy consumption of hydrogen is only 3.998 kW h m-3 H2, which is 19.8% lower than the existing industrial catalysts (4.79 kW h m-3 H2). Compared to the current hydrogen production in factories, producing one million tons of hydrogen is expected to save up to 8.87 billion kW h of energy, achieving ultra-low energy consumption in hydrogen production. The catalyst prepared in this study exhibits remarkable catalytic activity under industrial conditions, reducing the energy consumption of industrial-grade electrolytic water, and provides a new perspective for preparing efficient bifunctional electrocatalysts with porous structures on an industrial scale in the future.

Design and multilevel regulation of transition metal phosphides for efficient and industrial water electrolysis.

Renewable energy electrolysis of water to produce hydrogen is an effective measure to break the energy dilemma. However, achieving activity and stability at a high current density is still a key problem in water electrolyzers. Transition metal phosphides (TMPs), with high activity and relative inexpensiveness, have become excellent candidates for the production of highly pure green hydrogen for industrial applications. In this mini-review, multilevel regulation strategies including nanoscale control, surface composition and interface structure design of high-performance TMPs for hydrogen evolution are systematically summarized. On this basis, in order to achieve large-scale hydrogen production in industry, the hydrogen evolution performance and stability of TMPs at a high current density are also discussed. Peculiarly, the practical application and requirements in proton exchange membrane (PEM) or anion exchange membrane (AEM) electrolyzers can guide the advanced design of regulatory strategies of TMPs for green hydrogen production from renewable energy. Finally, the challenges and prospects in the future development trend of TMPs for efficient and industrial water electrolysis are given.

Te-doped-WSe2/W as a stable monolith catalyst for ampere-level current density hydrogen evolution reaction.

The development of efficient electrocatalysts for the hydrogen evolution reaction (HER) holds immense importance in the context of large-scale hydrogen production from water. Nevertheless, the practical application of such catalysts still relies on precious platinum-based materials. There is a pressing need to design high-performing, non-precious metal electrocatalysts capable of generating hydrogen at substantial current levels. We report here a stable monolith catalyst of Te-doped-WSe2 directly supported by a highly conductive W mesh. This catalyst demonstrates outstanding electrocatalytic performance and stability in acidic electrolytes, especially under high current conditions, surpassing the capabilities of commercial 5% Pt/C catalysts. Specifically, at current densities of 10 and 1200 mA cm-2, it exhibits a minimal overpotential of 79 and 232 mV, along with a small Tafel slope of 55 mV dec-1, respectively. The remarkable catalytic activity of Te-WSe2 can be attributed to the exceptional electron transfer facilitated by the stable monolithic structure, as well as the abundant and efficient active sites in the material. In addition, density functional theory calculations further indicate that Te doping adjusts H atom adsorption on various positions of WSe2, making it closer to thermal neutrality compared to the original material. This study presents an innovative approach to develop cost-effective HER electrocatalysts that perform optimally under high current density conditions.

Rise of wood-based catalytic electrodes for large-scale hydrogen production

The wood-based pretreatment strategy and active site loading strategy of wood-based catalytic electrodes make them valuable electrodes for water electrolysis, and they hold significant potential for industrial-scale water electrolysis.

Optimizing the active interface structure of MnO2 to achieve sustainable water oxidation in an acidic medium

Developing cost-effective electrocatalysts for the oxygen evolution reaction (OER) in proton exchange membrane (PEM) water electrolysis is crucial to achieving large-scale hydrogen production through water electrolysis.

Defect-balanced active and stable Co3O4−x for proton exchange membrane water electrolysis at ampere-level current density

Active and stable noble metal-free catalysts for the oxygen evolution reaction (OER) are essential for realizing large-scale hydrogen production using proton exchange membrane (PEM) electrolyzers.

Highly conductive and stable electrolytes for solid oxide electrolysis and fuel cells: fabrication, characterisation, recent progress and challenges

Solid oxide electrolyser (SOE) technology emerges as a promising alternative, typified by high-efficiency water-splitting capability and lower cost for large-scale hydrogen production. Electrolytes are the critical part of SOECs and SOFCs, which affect the performance and operation temperatures.

Pyrolysis of biogas for carbon capture and carbon dioxide-free production of hydrogen

The high-temperature pyrolysis of biogas for eco-friendly hydrogen production and simultaneous carbon capture is investigated, as it can contribute to a decarbonization of the chemical industry and may act as a carbon sink.