Efficient Electrocatalyst For Hydrogen Evolution Reaction Research Articles

Interface prompted highly efficient hydrogen evolution of MoS2/CoS2 heterostructures in a wide pH range.

Interfacial electronic characteristics are crucial for the hydrogen evolution reaction (HER), especially in nanoscale heterogeneous catalysts. In this work, we found that the synergistic activation of CoS2 and MoS2 (2H-MoS2 and 1T-MoS2) greatly enhances the HER activity in a wide pH range compared to those of each component. The Gibbs free energies for hydrogen adsorption at interfacial Co sites are as low as -0.08 (-0.25) eV and -0.20 (0.01) eV for 2H-MoS2/CoS2 and 1T-MoS2/CoS2 heterostructures in acidic (alkaline) media, respectively, which are even superior to that of Pt(111) (-0.09 eV). Moreover, the theoretical exchange current density of MoS2/CoS2 can reach ∼1.98 × 10-18 A site-1 (∼8.43 A mg-1). Experimentally, MoS2/CoS2 exhibits a greatly reduced overpotential of 54 (46) mV and a Tafel slope of 42 (50) mV dec-1 under acidic (alkaline) conditions. The improved performance mainly originates from the synergistically activated interfacial Co atoms with better electron localization and local bonding. The interfacial effect enhances the electron conductivity and improves the H adsorption characteristics, making MoS2/CoS2 highly valuable as efficient HER electrocatalysts.

Activation of metal-free porous basal plane of biphenylene through defects engineering for hydrogen evolution reaction

The biggest challenge in the commercial application of electrochemical reduction of water through the hydrogen evolution reaction (HER) is hampered due to the scarcity of inexpensive and efficient catalysts. Herein, we propose a metal-free biphenylene nanosheet, a recently proposed two-dimensional (2D) carbon allotrope, as an excellent HER electrocatalyst. The dynamical and thermal stability of biphenylene nanosheet is validated through phonon dispersion and abinitio molecular dynamics (AIMD) calculations, respectively. At a low H coverage (1/54), the biphenylene nanosheet shows excellent catalytic activity with the Gibbs free energy (ΔGH∗) of 0.082 eV. The Bdoping and C-vacancy in biphenylene further improve ΔGH∗ to −0.016 eV and 0.005 eV, respectively. The interactions between the H atom and the nanosheet are explained through the relative position of the p-band center. Our study opens new possibilities to use non-metallic porous materials as highly efficient electrocatalysts for HER.

Accessible active sites activated by nano cobalt antimony oxide @ carbon nanotube composite electrocatalyst for highly enhanced hydrogen evolution reaction

The electrochemical hydrogen evolution reaction (HER) was one of new energy development strategies with clean, efficient and renewable characteristics, and electrocatalysts play a crucial role in HER technology. Herein, a composite material (CSO@0.5CNT) derived from the combination of nano cobalt antimony oxide (CSO) with carbon nanotubes (CNT) through hydrothermal reaction, in which the nanoparticles of CSO were closely compounded on the surface of CNT, could be a highly efficient electrocatalyst for HER in 1 M KOH. The binary composite electrocatalyst of CSO and CNT reduced the internal resistance, promoted the charge transfer, exhibited a large electrochemical active area, and obtained the lower overpotential, with 155 mV at 10 mA/cm2 current density. Moreover, such a CSO@0.5CNT electrocatalyst displayed a small Tafel slope of 86.5 mV dec−1, excellent catalytic activity and extraordinary long-term structural stability after 30 h and 3000 CV cycles. Furthermore, the electrocatalytic mechanism revealed by Density Functional Theory (DFT) calculation proved that, the decomposition of H2O molecules was the control step of the whole HER, and the superior electron transport ability of CNT was favorable to the improvement of electrocatalytic performance. Benefitting from accessible active sites on carbon nanotube (C atom) and CSO (Co atom), the composite electrocatalyst of CSO@0.5CNT displayed synergistic effect for electrocatalytic HER properties, and that was the main mechanism for significantly improving the electrocatalytic activities. Our work provides a novel strategy towards high-efficiency electrocatalysts for hydrogen evolution reaction.

Controlled synthesis of NiCoP@NiM LDH (M=Cu, Fe, Co) as efficient hydrogen evolution reaction electrocatalyst

In the context of increasingly sophisticated chemistry, the production of hydrogen from water splitting has long been a promising process. The high purity of the product and low level of contamination make water splitting as an ideal way to produce hydrogen. In this paper, we designed a series of novel NiCoP@NiM LDH/NF catalysts (M=Cu, Fe, and Co) with a three-dimensional heterogeneous structure and outstanding hydrogen production efficiency. To better compare the hydrogen production efficiency of NiCoP@NiFe LDH/NF, we also performed the doping of other nonprecious metals Cu (NiCoP@NiCu LDH/NF) and Co (NiCoP@NiCo LDH/NF) and studied them as two extra catalysts. The NiCoP@NiFe LDH/NF electrodes display a low overpotential of only 119 mV at a current density of 10 mA·cm−2 in the alkaline environment of 1 M KOH for the hydrogen evolution reaction (HER). This superior performance of HER is related to the unique structure of NiCoP@NiFe LDH/NF. In addition, the Ni foam substrate has a three-dimensional network structure, the active site of the NiCoP@NiFe LDH/NF will be more easily exposed under the support of this unique structure. These experimental results and density functional theory (DFT) demonstrate that the NiCoP@NiFe LDH/NF electrode has the best electrochemical activity for HER.

Electrosynthesis of Low Pt‐Loaded High Entropy Catalysts for Effective Hydrogen Evolution with Improved Acidic Durability

The synergistic effect in multi‐metal electrocatalysts has gained attention as an efficient strategy for enhancing intrinsic electrocatalytic activities. In this study, a facile electrodeposition technique is used to synthesize a multi‐metal high entropy catalyst (HEC) for efficient electrocatalytic hydrogen production. To boost the synergistic effect between noble metals and transition metals, the Pt ratio is controlled in a multi‐metal electrocatalyst system. The prepared Pt‐involved HEC (Pt‐HEC) exhibits a bamboo‐like morphology with uniformly distributed elements. The 2.5 mM Pt‐HEC has outstanding electrocatalytic activity toward hydrogen evolution reaction (HER) among other Pt‐HECs, with a low overpotential of 70 mV and a Tafel slope value of 47 mV dec−1. Additionally, the Pt mass activity of the 2.5 mM Pt‐HEC is 5.6 times higher than commercial Pt/C electrocatalyst owing to the improved synergistic effect with an optimized Pt ratio. According to the electrochemical impedance spectroscopy (EIS) analysis, the proton‐coupled electron transfer (PCET) process occurs more quickly in the 2.5 mM Pt‐HEC electrocatalyst, confirming its smaller charge transfer resistance properties compared to those of the 5 and 1 mM Pt‐HEC. Therefore, HEC systems can be extensively encouraged as a platform for improving synergistic effects and enhancing electrocatalytic activities for a highly efficient HER electrocatalyst.

Bi-Porphyrins MOF with confinement and ion-attracting effects in concert with RuO2-doped CNT as efficient electrocatalysts for HER in acidic and alkaline media

It is highly desirable and challenging to design efficient and stable hydrogen evolution reaction (HER) electrocatalysts in a variety of acidic and alkaline media. Here, a novel ternary catalyst has been proposed consisting of ruthenium dioxide doped carbon nanotubes (denoted as RuO2@CNT) wrapped in a multi-step strategy with a first synthesis of a bismuth metal porphyrin-based organic framework as co-catalyst (denoted as RuO2@CNT@MOF). The addition of CNT improves not only the conductivity of the electrocatalyst but also the distribution of the active RuO2 particles. Furthermore, the highly symmetrical conjugated structure of Bi-TCPP MOF facilitates both the adsorption of hydrogen ions and the generation of hydroxyl radicals (•OH). The Bi-TCPP MOF encapsulated in the outer layer of RuO2@CNT enhances the mechanical strength and creates the confinement effect, leading to the synthesis of RuO2@CNT@MOF as a HER electrocatalyst that exhibits excellent catalytic performance and acid and base resistance. In particular, low overpotentials of 13 mV and 50 mV can be achieved to provide current densities of 10 mA cm−2 in alkaline and acidic media, respectively. Significantly, this work provides new ideas for the careful design and development of MOFs as co-catalysts to improve the overall performance of materials in energy-related fields.

Facet modulation of nickel-ruthenium nanocrystals for efficient electrocatalytic hydrogen evolution

Constructing highly active electrocatalysts towards hydrogen evolution reaction (HER) in both alkaline and acidic media is essential for achieving a sustainable energy economy. Here, a facile ethylene glycol reduction strategy was employed to design the nickel-ruthenium nanocrystals (Ni-Ru NC) with an exposed highly active Ru (101) facet as an efficient electrocatalyst for HER. Testings show Ni-Ru NC outperforms the benchmark catalyst Pt/C by delivering extraordinarily low overpotentials of 21.1 and 70.9 mV to drive 10 mA cm−2 in acidic and alkaline solutions, respectively. The results of experimental and theoretical studies suggest that Ni can modulate the electronic structure of the Ru NC and optimize the hydrogen adsorption free energy on Ru’s surface, which accelerates the charge transfer kinetics and enhances the HER performance. The study support the potential application of facet-modulated Ru-based HER eleccatalyst in an alkaline environment.

Metal-nonmetal atom co-doping engineered transition metal disulfide for highly efficient hydrogen evolution reaction

The development of effective and non-precious electrocatalyts for hydrogen evolution reaction (HER) has attracted massive research interests. Herein, we report a density functional theory (DFT) investigation on the activation and optimization of Molybdenum disulfide (MoS2) monolayer as efficient HER electrocatalysts by cobalt-nonmetal atom (X = B, C, N, P, Se) codoping. Our results show that three CoX-MoS2 (X = C, N, and Se) catalysts display enhanced HER performance with |ΔGH|s in the range of 0.12–0.23 eV. Careful electronic structure analysis manifests that the favorable H adsorption process on the MoS2 basal plane is induced by suitable in-gap states upon codoping. Furthermore, appropriate biaxial strain can help optimize the HER performance of these co-doped systems, e.g, the ΔGHs of CoC@MoS2, CoN@MoS2, and CoSe@MoS2 reaches 0.0 eV, −0.04 eV, and −0.01 eV at 1.86% tensile strain, 5% compressive strain, and 4% compressive strain, respectively. Our work offers a highly promising catalyst for HER and guides the atomic design of more efficient non-noble electrocatalysts.

Electronic Modulation of Metal–Organic Frameworks by Interfacial Bridging for Efficient pH‐Universal Hydrogen Evolution

AbstractDesigning well‐defined interfacial chemical bond bridges is an effective strategy to optimize the catalytic activity of metal–organic frameworks (MOFs), but it remains challenging. Herein, a facile in situ growth strategy is reported for the synthesis of tightly connected 2D/2D heterostructures by coupling MXene with CoBDC nanosheets. The multifunctional MXene nanosheets with high conductivity and ideal hydrophilicity as bridging carriers can ensure structural stability and sufficient exposure to active sites. Moreover, the Co–O–Ti bond bridging formed at the interface effectively triggers the charge transfer and modulates the electronic structure of the Co‐active site, which enhances the reaction kinetics. As a result, the optimized CoBDC/MXene exhibits superior hydrogen evolution reaction (HER) activity with low overpotentials of 29, 41, and 76 mV at 10 mA cm−2 in alkaline, acidic, and neutral electrolytes, respectively, which is comparable to commercial Pt/C. Theoretical calculation demonstrates that the interfacial bridging‐induced electron redistribution optimizes the free energy of water dissociation and hydrogen adsorption, resulting in improved hydrogen evolution. This study not only provides a novel electrocatalyst for efficient HER at all pH conditions but also opens up a new avenue for designing highly active catalytic systems.

Realizing Favorable Synergism Toward Efficient Hydrogen Evolution Reaction with Heterojunction Engineered Cu7S4/CuS2/NiS2 and Functionalized Carbon Sheet Heterostructures

AbstractElectrochemical hydrogen generation via water splitting is the greenest approach toward the hydrogen economy. To satisfy the practical utilization, the electrocatalyst for hydrogen evolution reaction (HER) must be of low cost with high catalytic activity. Accordingly, transition metal based electrocatalysts have attracted significant research interest. Herein, this work demonstrates an efficient HER electrocatalyst based on copper nickel sulfide (CNS), and Agaricus bisporus biomass derived functionalized carbon (FMCs) based nanocomposites, where the CNS are in situ hydrothermally grown in presence of FMCs. First, the effect of solvent (water, ethylene glycol, and glycerol) on the phase and crystallinity of CNS and their performance as HER electrocatalyst in acidic medium are demonstrated. The CNS heterojunction synthesized in aqueous medium (CNSW) shows the best HER catalytic activity with 269 mV (at 10 mA cm−2) overpotential and corresponding Tafel slope of 146.86 mV dec−1. Further, while the FMCs possess no catalytic activity itself, its control presence in the nanocomposites CNSW/FMCs nanocomposites caused a dramatic reduction in the HER overpotential (180 mV@10 mA cm−2) and the corresponding Tafel slope (78.71 mV dec−1). Notably, where the nonlayered metal sulfides generally are unstable in acidic medium, the synergistic interaction between the CNSW and FMCs enables stable catalytic activity for the measured 10 h.

Screening and design of 2D metal–organic frameworks for hydrogen evolution reaction through controlling transition metals and heteroligands

Two-dimensional (2D) metal–organic frameworks (MOFs) are potential electrocatalysts for hydrogen evolution reaction (HER). However, the origin of HER catalytic activities of 2D MOFs remains unclear. We herein design a series of 2D triphenylene-based MOFs as HER electrocatalysts candidates by tuning the composition of transition metals and homoligands/heteroligands. Among the 230 candidates, CuOS and AgOS were identified as ideal candidates as HER electrocatalysts, through a four-step screening strategy evaluating their stability, Gibbs free energies of H adsorption, different H coverages, and the kinetic barriers. In particular, we pointed that the p-band and p+d-band centers as intrinsic descriptors can directly evaluate the HER performance of 2D MOFs, due to the interaction between metals and ligands that can tune the electronic structure of the active center. Our work not only elucidates the structure–performance correlations of 2D MOFs but also provides the theoretical platform to design new 2D MOFs as efficient HER electrocatalysts.

NiCoP nanoarchitectures: One-step controlled electrodeposition and their application as efficient electrocatalysts for boosting hydrogen evolution reaction

Designing non-precious and long-lasting electrocatalysts with enhanced catalytic properties for hydrogen evolution reaction (HER) is a fundamental approach to address the needs for hydrogen industry and overcome the current challenges in sustainable energy generation. Herein, we present ternary NiCoP nanostructures synthesized through a direct and controlled electrochemical deposition at room temperature as highly efficient electrocatalysts for HER. Different Ni/Co ratios in the alloy were investigated resulting in different nanoarchitectured morphologies, chemical compositions and HER performances, in turn. The NiCoP–I alloy exhibited a nanoparticulated morphology comprising well-defined nanoparticles of ∼20–30 nm which evolved to nanoparticulated caps at prolonged electrodeposition times presenting a large electrochemical surface area of 526 cm2. The NiCoP–I electrocatalyst demonstrated a small Tafel slope of 49 mV dec−1 and an ultra-low overpotential of 68 mV vs. RHE at −10 mA cm−2 in alkaline solution which well rivals to that of Pt foil and outmatches its binary alloy counterparts.

Structural parameters, energy states and magnetic properties of the novel Se-doped NiFe2O4 ferrites as highly efficient electrocatalysts for HER

This study is devoted to NiFe 2 O 4 with different masses of Se (NFO + x%Se) (x = 0.0–4.0%) spinel ferrite nanoparticles production and investigation. The results of the crystal structure, microstructure and magnetic properties are presented as a function of the chemical content of the NFO + x%Se. Superparamagnetic (at 300 K) and ferrimagnetic (at 10 K) states are observed for all samples in the wide magnetic field range. The field dependencies of the magnetization show that Se-substitution does not change the main magnetic characteristics when x<2.0%. We observe a non-linear dependence of magnetic parameters for sample with x ≥ 2.0% (for NFO+2%Se, we determine the increase of the main magnetic parameters for 20% of the average values and the minimum values belong to the NFO+3%Se). The undoped sample and NiFe 2 O 4 +x%Se are soft magnets and characterized by the low coercivity (varying in the range 560–647 Oe). At T = 10 K squareness ratio (Sq. = Mr/Ms) is in a range of (0.216–0.318). This indicates a preferable single-domain state of crystallites, which differs from the magnetic structure at T = 300 K. Furthermore, the NFO + x%Se (x = 2.0) have a low overpotential of about −327 mV, and a small Tafel slope of 91 mV/dec, which makes it a better for HER (hydrogen evolution reaction) catalyst than the undoped NiFe 2 O 4 .

Nickel-based nanosheets array as a binder free and highly efficient catalyst for electrochemical hydrogen evolution reaction

Hydrogen technology through water electrolyzer systems has attracted a great attention to overcome the energy crisis. So, rationally designed non-noble metal based-electrocatalysts with high activity and durability can lead to high performance water electrolyzer systems and high purity hydrogen generation. Herein, a facile two-step method: hydrothermal and electrodeposition, respectively, are developed to decorate highly porous three-dimensional binder-free structure NiFeO/NiO nanosheets array on Ni foam (NiFeO/NiO/NF) with robust adhesion as a high-performance electrode for Hydrogen Evolution Reaction (HER).The electrodeposition process applied after the initial hydrothermal process provides a stable structure and, in addition, enhances the sluggish hydrogen evolution efficiency. In alkaline media, the developed electrode needs an overpotential of 48 and 188 mV to drive current densities (j) of 10 and 100 mA cm−2, respectively. After continuous 110 h electrochemical stability test under j = 150 mA cm−2 conditions, demonstrates an excellent stability with ignorable activity decrease. Such superior HER catalytic performance can be derived from the synergistic effect between Ni and Fe atoms, also exposure to a high number of active sites on the nanosheets, and good dynamic with effective electron transport along the nanosheets. The present work provides a promising route for the design and fabrication of cost-effective and highly efficient HER electrocatalysts.

Optimizing the electronic structure of CoNx via coupling with N-doped carbon for efficient electrochemical hydrogen evolution

Transition metal nitrides (TMNs) have been regarded as an excellent class of electrocatalysts for hydrogen evolution reaction (HER), but there is still huge room for improvement. In this work, cobalt nitride (CoNx) coupled with N-doped carbon (NC) and supported by nickel foam (NF) is designed as an efficient HER electrocatalyst (NF/CoNx@NC). The introduction of NC can not only optimize the electronic structure of CoNx to boost the intrinsic activity, but also enhance the electronic conductivity and stability of the catalyst. As a result, NF/CoNx@NC exhibits excellent HER performance. On the one hand, it only needs an overpotential of 69 mV to deliver a current density of 20 mA cm−2 in 1.0 mol/L KOH, far better than that of CoNx (182 mV). On the other hand, the electronic conductivity and stability of the catalyst can be significantly enhanced after the introduction of NC. This work has done successful material design with the goal of enhancing the intrinsic activity, electronic conductivity, and stability, which has certain reference and guiding significance for the design of novel transition metal-based electrocatalysts.

Unveiling high intrinsic activity of Co3Mo alloy and metallic Ni embedded in CoNiMo-O nanosheets arrays for hydrogen evolution reaction

Developing robust and efficient electrocatalysts to boost hydrogen evolution reaction (HER) in alkaline solution is a crucial issue for H2 energy. One of the effective strategies is to fabricate excellent electrocatalysts by embedding carbon shell-encapsulated transition metals or alloys in metal oxides through metal–organic frameworks (MOFs) as precursor. Herein, three multiphase composite HER catalysts (NF/CoNiMo-500, 600, 700) are exploited by using NF/CoNi-MOF-74 as template. Specially, the NF/CoNiMo-500 shows optimal HER activity, which is constructed by nesting graphitized carbon wrapped Co3Mo alloy and metallic Ni nanoparticles into amorphous CoNiMo-oxide (CoNiMo-O) nanosheets. It requires the lowest overpotential of 34 mV to reach the current density of 10 mA/cm2, demonstrating the smallest Tafel slope of 58 mV/dec. Importantly, the water-alkali electrolyzer applying NF/CoNiMo-500 as cathode and NF/IrO2 as anode exhibits a low voltage of 1.39 V at 10 mA/cm2 and good stability. The density functional theory (DFT) calculations reveal the high intrinsic activity of Co3Mo alloy and metallic Ni contributes significantly to the optimal electrocatalytic performance of CoNiMo-500. This work opens up a new orientation to synthesize microscale MOF-74 arrays and develop efficient HER electrocatalysts by combining carbon shell-encapsulated metals and alloys with oxides.

Manipulating the Water Dissociation Electrocatalytic Sites of Bimetallic Nickel-Based Alloys for Highly Efficient Alkaline Hydrogen Evolution.

Transition-metal alloys are currently drawing increasing attention as promising electrocatalysts for the alkaline hydrogen evolution reaction (HER). However, traditional density-functional-theory-derived d-band theory fails to describe the hydrogen adsorption energy (ΔGH ) on hollow sites. Herein, by studying the ΔGH for a series of Ni-M (M=Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Mo, W) bimetallic alloys, an improved d-band center was provided and a potential NiCu electrocatalyst with a near-optimal ΔGH was discovered. Moreover, oxygen atoms were introduced into Ni-M (O-NiM) to balance the adsorption/desorption of hydroxyl species. The tailored electrocatalytic sites for water dissociation can synergistically accelerate the multi-step alkaline HER. The prepared O-NiCu shows the optimum HER activity with a low overpotential of 23 mV at 10 mA cm-2 . This work not only broadens the applicability of d-band theory, but also provides crucial understanding for designing efficient HER electrocatalysts.

Manipulating the Water Dissociation Electrocatalytic Sites of Bimetallic Nickel‐Based Alloys for Highly Efficient Alkaline Hydrogen Evolution

AbstractTransition‐metal alloys are currently drawing increasing attention as promising electrocatalysts for the alkaline hydrogen evolution reaction (HER). However, traditional density‐functional‐theory‐derived d‐band theory fails to describe the hydrogen adsorption energy (ΔGH) on hollow sites. Herein, by studying the ΔGH for a series of Ni−M (M=Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Mo, W) bimetallic alloys, an improved d‐band center was provided and a potential NiCu electrocatalyst with a near‐optimal ΔGH was discovered. Moreover, oxygen atoms were introduced into Ni−M (O−NiM) to balance the adsorption/desorption of hydroxyl species. The tailored electrocatalytic sites for water dissociation can synergistically accelerate the multi‐step alkaline HER. The prepared O−NiCu shows the optimum HER activity with a low overpotential of 23 mV at 10 mA cm−2. This work not only broadens the applicability of d‐band theory, but also provides crucial understanding for designing efficient HER electrocatalysts.

Recent Advances in Carbon‐Supported Noble‐Metal Electrocatalysts for Hydrogen Evolution Reaction: Syntheses, Structures, and Properties

AbstractThe electrochemical hydrogen evolution reaction (HER) that converts renewable electricity into storable hydrogen, a sustainable and clean energy carrier, provides a promising method to mitigate the energy crisis and environmental pollution. In general, noble‐metal‐based nanomaterials (including Pt, Rh, Ru, Ir, etc.) have drawn tremendous research attention in the context of the HER because of their nearly optimal bindings to hydrogen, robust stability and tunable physical/chemical properties. Particularly, carbon as a substrate not only offers a stabilizing and conductive matrix, but also impacts the electronic structure of the supported metal by interfacial interaction, necessitating a detailed understanding. To speed up the sluggish kinetics of the HER, the design and construction of efficient electrocatalysts is of crucial importance. Herein, a comprehensive review of the recent advances in carbon‐supported noble‐metal electrocatalysts is presented, focusing on their synthetic strategies, structural analyses, and applications in HER electrocatalysis. Specifically, the correlation between the electronic structure and activity is discussed. Furthermore, a perspective is offered highlighting the challenges and opportunities for development of highly efficient HER electrocatalysts, with the aim for widespread utilization of practical water electrolyzers toward green hydrogen production.

Electrochemically activated Ni@Ni(OH)2 heterostructure as efficient hydrogen evolution reaction electrocatalyst for anion exchange membrane water electrolysis

Efficient and cost-effective catalysts are vital for sustainable hydrogen production via water electrolysis. In this study, we propose a facile method of fabricating a Ni@Ni(OH)2 heterostructure catalyst on a Ti paper substrate by combining electrodeposition and subsequent electrochemical activation. Detailed characterization and analysis revealed the formation of Ni (oxy)hydroxides. Ni@Ni(OH)2 underwent surface reconstruction, resulting in the formation of abundant heterojunctions and electron modulation during electrochemical activation, which substantially increased the exposed surface area facilitating the adsorption of intermediates during the hydrogen evolution reaction (HER). Thus, the resulting activated Ni@Ni(OH)2/Ti electrode exhibited significantly improved HER activity in the half-cell test, reaching a current density of −10 mA/cm2 at an overpotential of 58 mV with a Tafel slope of 83 mV/dec. When applied to anion exchange membrane water electrolysis, a single cell comprising an Ni@Ni(OH)2/Ti cathode and commercial IrO2/CP anode exhibited a maximum current density of 1.00 A/cm2 at a potential of 2.0 Vcell, demonstrating superior performance to commercial Pt/C electrodes in the high-current-density region above 2.0 A/cm2.