Green Hydrogen Energy Research Articles

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.

Encapsulating Transition Metal Nanoparticles inside Carbon (TM@C) Chainmail Catalysts for Hydrogen Evolution Reactions: A Review

Green hydrogen energy from electrocatalytic hydrogen evolution reactions (HERs) has gained much attention for its advantages of low carbon, high efficiency, interconnected energy medium, safety, and controllability. Non-precious metals have emerged as a research hotspot for replacing precious metal catalysts due to low cost and abundant reserves. However, maintaining the stability of non-precious metals under harsh conditions (e.g., strongly acidic, alkaline environments) remains a significant challenge. By leveraging the curling properties of two-dimensional materials, a new class of catalysts, encapsulating transition metal nanoparticles inside carbon (TM@C) chainmail, has been successfully developed. This catalyst can effectively isolate the active metal from direct contact with harsh reaction media, thereby delaying catalyst deactivation. Furthermore, the electronic structure of the carbon layer can be regulated through the transfer of electrons, which stimulates its catalytic activity. This addresses the issue of the insufficient stability of traditional non-precious metal catalysts. This review commences with a synopsis of the synthetic advancement of the engineering of TM@C chainmail catalysts. Thereafter, a critical discussion ensues regarding the electrocatalytic performance of TM@C chainmail catalysts during hydrogen production. Ultimately, a comprehensive review of the conformational relationship between the structure of TM@C chainmail catalysts and HER activity is provided, offering substantial support for the large-scale application of hydrogen energy.

Efficient and durable OER electrocatalysts through vacancy engineering and core-shell structure design in acidic environment

The electrocatalytic conversion of water into green hydrogen energy through overall water splitting advances sustainable energy goals. However, it is limited by the slow kinetics of the oxygen evolution reaction (OER) and durability challenges at high potentials. Here, we rationally develop a series of Mn-doped RuO2-coated Ru (Mn-Ru@RuO2) catalysts involving unique core-shell structures and abundant lattice distortions induced by oxygen defects. The optimal Mn-Ru@RuO2 sample demonstrated robust activity, achieving a low overpotential of 220 mV at 10 mA cm−2. Notably, this sample exhibited minimal degradation after 220 h and a 25.5-fold increase in mass activity (1.37 A mgRu−1) compared to commercial RuO2 at an overpotential of 300 mV. These results suggest that regulated oxygen deficiencies and optimal Ru3+/Ru4+ ratios facilitate the lattice oxygen oxidation (LOM) mechanism and the formation of a high concentration of ∗OH radicals, enhancing acidic OER performance. Additionally, the unique core-shell structures effectively prevent over-oxidation of the RuO2 shell, ensuring superior durability. This research not only breaks the trade-off of electrochemical activity and durability, but also provides valuable insights into the design of highly efficient and stable electrocatalysts.

Constructing a Z-scheme heterojunction of oxygen-deficient WO3-x and g-C3N4 for superior photocatalytic evolution of H2

Semiconductor-based photocatalytic water splitting enables the conversion of abundant solar energy to green and renewable hydrogen energy. Graphitic carbon nitride (g-C3N4) is synthesized using a straightforward method, demonstrating stable physicochemical properties and possessing an optimal bandgap, thus positioning it as a promising photocatalyst in the realm of environmental sustainability. Oxygen vacancies are extensively employed to modulate light absorption and surface properties of metal-oxide semiconductors. In this study, g-C3N4 nanosheets were coupled with oxygen-deficient tungsten trioxide (WO3-x) to form heterojunction photocatalysts (X-WOCN). Comprehensive material characterization results demonstrated that the constructed heterojunction extended the visible light absorption range, improved photogenerated electron-hole separation efficiency, and thus augmented photocatalytic activity. Notably, the optimum hydrogen evolution rate of 6%-WOCN was enhanced by 5.4-fold compared to that of g-C3N4. Furthermore, we propose a Z-scheme heterojunction charge separation mechanism mediated by oxygen defects and support this mechanism through detection of surface-active substances •O2− and •OH. This study offers novel propositions into the function of oxygen defects in facilitating charge separation within Z-scheme heterojunction.

Ru/NiMnB spherical cluster pillar for highly proficient green hydrogen electrocatalyst at high current density

Advanced OER/HER electrocatalytic alternatives are crucial for the wide adaptation of green hydrogen energy. Herein, Ru/NiMnB spherical cluster pillar (SCP), denoted as Ru/NiMnB, is synthesized using a combination of electro-deposition and hydrothermal reaction. Systematic investigation of Ru doping in the NiMnB matrix revealed significant improvements in electrocatalytic performance. The Ru/NiMnB SCPs demonstrate superior OER/HER activity with low overpotentials of 150 and 103 mV at 50 mA/cm2 in 1 M KOH, making them highly competitive with state-of-the-art electrocatalysts. Remarkably, the Ru/NiMnB SCPs exhibit a low 2-E cell voltage of 2.80 V at ultra-high current density of 2,000 mA/cm2 in 1 M KOH, outperforming the standard benchmark electrodes of RuO2 || Pt/C, thereby positioning Ru/NiMnB as one of the best bifunctional electrocatalysts. These SCPs exhibit exceptional high-current characteristics, stability and corrosion resistance, as evidenced by continuous operation at 1,000 mA/cm2 high-current density for over 150 h in 6 M KOH at elevated temperatures under harsh industrial conditions. Only a small amount of Ru incorporation significantly enhances the electrocatalytic performances of NiMnB, attributed to increased active sites and improved intrinsic properties such as conductivity, adsorption/desorption capability and reaction rates. Consequently, Ru/NiMnB SCPs present a promising bi-functional electrode concept for efficient green H2 production.

Novel BDD-loaded bimetallic phosphide electrodes enable interesting bifunctional seawater electrolysis

The direct electrolysis of seawater for the production of green hydrogen energy is an economically attractive approach. However, this technique confronts technical problems because to the oxygen evolution reaction (OER) weak stability and inadequate selectivity due to competition with the chlorine evolution process. This work focuses on improving the stability of the electrode and electrolysis efficiency. The phosphating NiCoP active layer with 3D porous morphology was created by electrodeposition on the B-doped diamond (BDD) as an electrode inspired by the bifunctional catalysis strategy. The successfully constructed unique cube-on-nanosheets structure in the NiCoP active layer enables the electrode to exhibit excellent electrocatalytic performance. The porous NiCoP/BDD (Por-NiCoP/BDD) electrodes showed good catalytic activity in alkaline-simulated seawater with the OER and hydrogen evolution reaction (HER) overpotentials of 400 and 261 mV, respectively, at a current density of 100 mA cm−2. More importantly, the electrode exhibits interesting stability of the catalytic performance and structural in alkaline-simulated seawater electrolysis, with the current density decaying by only 1.52 % and 4.06 % after OER and HER processes for 50 h, respectively. This work expands the valuable application scenarios of BDD electrode and provides novel ideas for the development of seawater electrolysis.

Cerium-doped construction of oxygen vacancies in IrO2 to promote acidic OER reaction

Proton exchange membrane electrolysis of water is currently recognized in the world as an up-and-coming method for the preparation of green hydrogen energy. Due to its sustainability and low pollution, it has attracted much attention from practitioners recently. The most advanced iridium oxide (IrO2) is the most promising catalyst.However, developing a highly efficient and stable IrO2 catalyst that can adapt to industrial conditions remains a terrific challenge. One of the main problems to be solved is that the slow oxygen evolution reaction(OER) at the anode limits the production of hydrogen. We propose a straightforward method for synthesizing Ce metal-doped IrO2 with a high oxygen vacancy concentration while simultaneously improving the IrO2 catalytic activity and stability.The Ce-doped IrO2 (Ce-IrO2) exhibits a microscopic nanoparticle morphology and a high density of oxygen vacancies, enabling a rapid oxygen evolution reaction (OER) process with a low overpotential of 240 mV at 10 mA·cm-2 and a remarkable stability of over 50 h under acidic conditions.A growing body of research shows a synergistic effect of oxygen vacancies and mental dopants on the adsorption and evolution of active intermediates in the active center so that the oxygen evolution reaction activity of the Ir-based catalyst can be improved. We hope that ourwork will provide a sample method for acquiring catalysts capable of adapting to a wide range of conditions via metal doping.

Nanoarchitectonics of few-layer Ni3Fe nanosheets embedded porous nitrogen-doped carbon derived from asphalt waste: An efficient electrocatalyst for oxygen evolution reaction

The design and fabrication of stable, high-performance, and affordable oxygen evolution reaction (OER) electrocatalysts is essential for performing practical water electrolysis and generating green hydrogen energy. Here, we report that 2D few layer Ni3Fe nanosheets embedded with 2D porous nitrogen doped carbon (N-NixFe@CF) from asphalt waste and then convolved and assembled into 1D hollow nanotube structures by Lewis acid molten salt etching method, which were used as electrocatalysts for OER. Benefiting from the integrate of 1D hollow nanotube structure and 2D porous nanosheets, the close contact between catalysts and support, and the increased conductivity, the resultant N-Ni3Fe@CF catalysts exhibited high catalytic activities in the OER with low overpotential at a current density of 10 mA cm−2 (114 mV), low Tafel slope (166.6 mV dec−1), and excellent electrochemical stability. This work provides a new concept for expanding the use of asphalt wastes and by-products, as well as a straightforward synthesis method for producing economical, efficient, and long-lasting alkaline OER electrocatalysts.

Recent research progress of MOFs-based heterostructures for photocatalytic hydrogen evolution

The growing serious energy crisis and environmental pollution expedite the development of green hydrogen energy. Photocatalytic water splitting technology, converting solar energy into chemical energy directly, provides a clean and economical way for hydrogen evolution. For the past few years, metal–organic frameworks (MOFs) semiconductor materials have become a research hotspot in the field of photocatalytic hydrogen evolution (PHE) due to their multiple advantages, including adjustable structure, high porosity, large specific surface area, abundant active sites, and so forth. Besides this, the construction of heterogeneous structures based on MOFs materials can further improve PHE performance through the effective internal electric field directional transfer of photogenerated electrons and the superior utilization rate of sunlight in comparison to the single MOFs photocatalyst. Herein, in this minireview, we summed up the varieties of synthesis methods of diverse types of MOFs heterojunction complex materials, discussed the H2 evolution efficiency based on this heterostructure photocatalyst in detail, and lastly proposed the advantages, limitations, and outlook of MOFs composites in the PHE field. We sincerely hope this review can provide a reference for future research based on MOFs materials for alleviating the current energy crisis.

Ultrafast Charge Transfer Dynamics in Multifaceted Quaternary Te–MoTe2–MoS2/ZnO S-Scheme Heterostructured Nanocatalysts for Efficient Green Hydrogen Energy

Ultrafast Charge Transfer Dynamics in Multifaceted Quaternary Te–MoTe₂–MoS₂/ZnO S-Scheme Heterostructured Nanocatalysts for Efficient Green Hydrogen Energy

A comprehensive review of production, applications, and the path to a sustainable energy future with hydrogen.

Green hydrogen, a versatile and sustainable energy carrier, has garnered increasing attention as a critical element in the global transition to a low-carbon economy. This review article comprehensively examines the production, applications, and potential of green hydrogen, accompanied by the challenges and future prospects associated with its widespread adoption. The production of green hydrogen is a central focus, due to its environmental benefits and distinctive characteristics. The article delves into the various techniques and technologies employed in green hydrogen production, emphasizing the need for cost reduction and increased scale for economic viability. Focusing particularly on applications, the review discusses the diverse sectors where green hydrogen demonstrates immense promise. Challenges and limitations are explored, including the intermittent nature of renewable energy sources, high production costs, and the need for extensive hydrogen infrastructure. The article also highlights the pressing need for innovation in electrolysis technology and materials, emphasizing the potential for cost reduction and increased efficiency. As industries gradually transition to green hydrogen as a cleaner feedstock, its demand and cost-competitiveness are projected to increase. This review article thoroughly evaluates the current status of green hydrogen and provides valuable insights into its potential role in the transition to a sustainable energy system.

The electrocatalytic reduction of nitrate to ammonia (NARR) using MOF-808 enhanced by the transition metal Fe (III) and H2PO4−/HPO42−

The combustion of fossil fuels has led to a surge in global CO2 emissions, causing environmental pollution and climate change issues that cannot be ignored. Ammonia, a green and carbon-free hydrogen energy, is emerging as a promising contender for new renewable fuels. Electrocatalytic nitrate-to-ammonia reduction reaction (NARR) is an emerging green synthesis method compared to the Haber-Bosch approach, and its performance is mainly controlled by selective hydrogenation. In this work, we report an efficient Fe@MOF-808-H2PO4−/HPO42− electrocatalyst (donated as Fe@MOF-808-P) for the electrocatalytic reduction of nitrate-to-ammonia. The results showed that the highest Faraday efficiency of NH3 (FENH3) is 90.8 ± 0.5 % at −0.9 V versus reversible hydrogen electrode (vs. RHE) in a 0.5 M potassium sulfate (K2SO4) solution containing nitrite (NO3−), the corresponding NH3 yield and specific activity are 420.4 ± 18.1 μmol h−1 cm−2 and 1035.9 ± 20.1 mgNH3 h−1 mgFe, respectively.Furthermore, a comparative analysis of the catalytic performance of Fe@MOF-808-H2O, MOF-808, MOF-808-P, and carbon cloth (CC) revealed that introducing P could accelerate the hydrogenation process of NO3− in the NARR process, confirming that Fe is the primary active center. Additionally, the cyclic electrolysis experiment demonstrated that the catalyst showed excellent stability. The results highlighted the promising potential of ammonia for future applications in renewable energy systems.

Environment-Benign Colloidal Quantum Dots-Modified Dual Photoelectrodes for Self-Biased Photoelectrochemical Water Splitting.

Photoelectrochemical (PEC) water splitting based on colloidal quantum dots (QDs) presents a promising approach for utilizing solar energy to produce green hydrogen energy. Previous research has been mainly focused on the single-photoelectrode QDs-PEC device operated under external bias, while the investigation of dual-photoelectrode configuration for self-biased QDs-PEC system is still lacking. In this work, two types of eco-friendly Cu-AISe/ZnSe:Cu (CZAC) and Mn-AIS/ZnS@Cu (MAZC) QDs were used to respectively sensitize the semiconductor n-type TiO2 and p-type Cu2O photoelectrodes, which acted as the photoanode and photocathode to build a heavy metal-free QDs-based bias-free solar water splitting cell, yielding a maximum photocurrent density of 0.47 mA cm-2 and a solar-to-hydrogen (STH) efficiency of 0.4 % under 1 sun AM 1.5G illumination (100 mW cm-2). Moreover, approximate 692 nmol of H2 and 355 nmol of O2 with molar ratio of ~2 : 1 was detected after two hours of continuous light illumination, demonstrating the effective overall water splitting. This work indicates a significant advancement towards the realization of a cost-effective, efficient and "green" QDs-based artificial solar-to-fuel conversion system.

Fabrication of Ru-doped CuMnBP micro cluster electrocatalyst with high efficiency and stability for electrochemical water splitting application at the industrial-level current density

Electrochemical water splitting has been considered as a key pathway to generate environmentally friendly green hydrogen energy and it is essential to design highly efficient electrocatalysts at affordable cost to facilitate the redox reactions of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). In this work, a novel micro-clustered Ru/CuMnBP electrocatalyst is introduced, prepared via hydrothermal deposition and soaking-assisted Ru doping approaches on Ni foam substrate. Ru/CuMnBP micro-clusters exhibit relatively low HER/OER turnover overpotentials of 11 mV and 85 mV at 10 mA/cm2 in 1 M KOH. It also demonstrates a low 2-E turnover cell voltage of 1.53 V at 10 mA/cm2 for the overall water-splitting, which is comparable with the benchmark electrodes of Pt/C||RuO2. At a super high-current density of 2000 mA/cm2, the dual functional Ru/CuMnBP demonstrates an exceptionally low 2-E cell voltage of 3.13 V and also exhibits superior stability for over 10 h in 1 M KOH. Excellent electrochemical performances originate from the large electrochemical active surface area with the micro cluster morphology, high intrinsic activity of CuMnBP micro-clusters optimized through component ratio adjustment and the beneficial Ru doping effect, which enhances active site density, conductivity and stability. The usage of Ru in small quantities via the simple soaking doping approach significantly improves electrochemical reaction rates for both HER and OER, making Ru/CuMnBP micro-clusters promising candidates for advanced electrocatalytic applications.

Modulation of the multiphase phosphorus/sulfide heterogeneous interface via rare earth for solar‐enhanced water splitting at industrial‐level current densities

AbstractPhotoelectrically coupling water splitting at high current density is a promising approach for the acquisition of green hydrogen energy. However, it places significant demands on the photo/electrocatalysts. Herein, rare earth elements doping NiMoO4‐based phosphorus/sulfide heterostructure nanorod arrays (RE‐NiMo‐PS@NF [RE = Y, Er, La, and Sc]) are obtained for solar‐enhanced electrocatalytic water splitting at high current densities. The results of the experiment and density‐functional theory studies illustrate that the Y element as a dopant not only makes the NiMoP2/NiMo3S4/NiMoO4 heterostructure exhibit excellent solar‐enhanced electrocatalytic activity (hydrogen evolution reaction [HER]: η1000 = 211 mV, oxygen evolution reaction [OER]: η1000 = 367 mV) but also optimizes the heterostructure interfacial electron density distributions and HER free energy. In addition, Y‐NiMo‐PS@NF achieves 18.64% solar‐to‐hydrogen efficiency. This study not only provides a new way to synthesize heterostructure electrocatalysts but also inspires the application of solar enhancement strategies for high current density water splitting.

Exploring the thermomechanical and dynamical mode switch transition of a reversible solid oxide cell

Reversible solid oxide cells (r-SOCs) are regarded as a solution form of clean energy generation towards a green hydrogen energy transition. However, during transportation, installation, and operation, they are required to withstand dynamic conditions as they face thermal, mechanical, and vibrational effects. Assessing the interplay of the thermomechanical and dynamical impacts on r-SOC materials during the mode-switch from electrolysis to fuel cell operation is the subject of this current comprehensive study. Advanced FEM-based homogenisation techniques have been harnessed in predicting and evaluating the detailed transients during static and dynamic loading. The intricate 3D thermal profiles throughout the transient reversible dual-modus operation from a typical r-SOC study have been derived using advanced image processing. Orthotropic material properties were incorporated into a unified macroscopic scale model by deriving the complex 3D microstructure geometry characteristics of the cell materials and component layers. The comprehensive thermomechanical and pre-stressed modal analysis results showed that the static and dynamic forces in fuel cell mode are more pronounced, whereas, in electrolysis operation, the dynamical behaviour highly depends on geometrical and operating conditions. Smaller component size shows higher natural frequencies and more intense vibration, leading to higher deformation attributed to complex mode shapes and reduced flexural rigidity. These insights are essential for optimizing r-SOC design parameters, enhancing their dynamic and structural reliability throughout their dual-mode operation lifespan.

An efficient and robust noble-metal-free self-standing bifunctional water electrolysis catalyst: Co3S4@Ex.NiFe-LDH for alkaline water electrolysis

Electrolysis of water integrated with the renewable energy as input source can contribute significantly in the production of green hydrogen, a clean and versatile energy carrier. In water electrolyzer, the hydrogen evolution reaction (HER) at the cathode must act synchronously with the oxygen evolution reaction (OER) at the anode to effectively accomplish total water-splitting. The performance of an electrolyzer is often limited by the low performance of anode and it is important to develop an electrocatalyst which can efficiently perform both HER and OER. Ni and Fe based layered-double-hydroxides (LDHs) have gained a lot of interest owing to their outstanding OER electrocatalytic activity, however they are known to have poor HER performance. To enhance the overall water splitting efficiency of the LDHs, we present a simple approach of preparing a heterojunction of LDH with cobalt sulphide. The bifunctional electroactivity of the designed electrocatalyst Co3S4@Ex.NiFe-LDH, worked efficiently in both HER and OER electrocatalysis. Chalcogenides known for HER, not only improves the HER performance of the composites but also found to reduce the charge transfer resistance. Obtained results showed that when it comes to the OER performance, the recommended catalyst shadows the state of art catalyst RuO2. Additionally, the catalyst has outstanding activity and stability, achieving a current density of around −120 mA/cm2 over a six-day period. The electrolyzer composed of both anode and cathode designated as Co3S4@Ex.NiFe-LDH||Co3S4@Ex.NiFe-LDH only needs a low voltage input of 1.49 V to achieve a total water splitting reaction at required current density of 10 mA/cm2, showing efficacy at the low voltage input. Experimental observations showed Co3S4@Ex.NiFe-LDH performs better than Pt/C–RuO2 in alkaline water electrolysis. The electrolyzer can continuously produce hydrogen at 50 mA/cm2 for more than a week period; indicating its potential for long-term application.

Three-dimensional pine-tree-like bimetallic sulfide with maximally exposed active sites by secondary structural restructuring for efficient electrocatalytic OER

Developing efficient, low-cost and bifunctional catalysts with predominant durability for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) is an extraordinary challenge in the preparation of green hydrogen energy by electrochemical water splitting. Three-dimensional (3D) transition metal compounds have become a research hotspot as OER electrocatalysts, which can replace noble metal oxides such as RuO2 and IrO2 to reduce application costs. Herein, we synthesized a novel three-dimensional pine-tree-like bimetallic sulfide arrays on nickel foam (FeCoS/NF) using various optimization strategies such as morphology optimization, in situ growth and introduction of heterogeneous structures. The as-synthesized FeCoS/NF electrocatalyst only requires relatively low overpotential of 156 mV to achieve a current density of 20 mA cm−2 for OER, with a Tafel slope of only 37 mV dec−1. It also has a small charge transfer resistance, an electrochemical surface area and good electrochemical stability in alkaline electrolytes. The excellent performance of FeCoS/NF can be attributed to the synergistic effect and amorphous phase of FeCoS as well as the well-defined pine-tree-like array architecture with a large surface area, abundant active sites, and sufficient gas and electrolyte diffusion channels.

Green hydrogen in Africa: opportunities and limitations

Green hydrogen is globally seen as a universal fuel, feedstock or energy carrier and storage. The study aims to examine the role of the emerging green hydrogen market in developing countries in Africa. The goal is to indentify key factors that may either positively or negatively affect the development of green hydrogen energy in Africa. Several developing countries have been identified as potential key players in green hydrogen production: South Africa, Egypt, Morocco, and Namibia. These countries are expected to play a vital part in the development of hydrogen technologies due to favourable climatic conditions for the production of low-cost renewable energy, the possibility of exporting hydrogen to EU countries, and the presence of various national policy initiatives (national hydrogen strategies) and international partnerships (the Africa Green Hydrogen Alliance). The results showed that green hydrogen will boost economic development in African countries, stimulate investment and create new jobs. The study also identifies several barriers that could affect the development of green hydrogen in Africa: high investment costs for hydrogen infrastructure, financing, weak institutions, water scarcity and the imbalance between hydrogen for local use and for export.

Influence of anodic treatment of nickel in deep eutectic solvents on electrocatalytic activity in oxygen evolution and urea oxidation reactions

The influence of anodic potentiostatic treatment of nickel surface in deep eutectic solvents, ethaline and reline (eutectic mixtures of choline chloride with ethylene glycol and urea, respectively), on the electrocatalytic activity in the electrochemical reactions of oxygen evolution and urea oxidation in an aqueous alkaline medium (1 M NaOH) was investigated for the first time. It was shown that, depending on the chosen treatment potential and the nature of the eutectic solvent used, a significant increase in the rate of the studied processes was observed. Specifically, after anodic treatment of nickel under certain conditions, the polarization of the oxygen evolution reaction at a current density of 0.1 A/cm2 could be reduced by approximately 150–200 mV, and the maximum current density of urea oxidation could be increased by an order of magnitude (from 0.012 A/cm2 to 0.131 A/cm2 at a urea concentration of 0.33 mol/dm3 in alkaline solution). The observed increase in electrocatalytic activity after anodic treatment of nickel in deep eutectic solvents is likely related to changes in surface morphology patterns and the nature and concentration of relevant electroactive sites on the electrode surface. The results obtained in this work can be used for the development of highly efficient electrode materials for green hydrogen energy.