Accelerated Charge Transfer Research Articles

Photochemical Synthesis of Porous Triazine-/Heptazine-Based Carbon Nitride Homojunction for Efficient Overall Water Splitting.

Porous triazine-/heptazine-based carbon nitride (THCN) homojunction with chloride (Cl) doping was synthesized by a simple, one-step photochemical synthesis route for efficient visible-light-driven overall water splitting. The phase ratio of triazine-based carbon nitride (TCN) and heptazine-based carbon nitride (HCN), texture and morphology of the THCN isotype junction were finely tuned by varying ultraviolet irradiation time and washing solvents. After washing with acetonitrile, the resulting porous THCN nanosheets with 48 h irradiation contain 21 wt % TCN and 79 wt % HCN units and reveal a significantly improved photocatalytic performance with H2 and O2 production rates up to 7.9 and 4.2 μmol h-1 , respectively, about 3.8 times higher than that of THCN prepared by 36 h illumination. The dual-phase interaction, holey structure, and Cl dopants favor the exposure of active sites, extended visible-light harvesting, accelerated charge transfer, and enhanced photoreduction ability, thereby improving photocatalytic activity.

Acid-tailored self-assembled perylene diimide supramolecular for visible-light-driven activation of peroxymonosulfate towards efficient degradation of iohexol

The presence of iohexol (IOX) in the environment has attracted widespread attention. Acetic acid, hydrochloric acid, and nitric acid tailored self-assembled perylene diimides (PA, PC and PN) were prepared and utilized in different visible-light-driven activation of peroxymonosulfate (PMS/Vis) systems for the degradation of IOX. As an electron acceptor, PMS can significantly hinder the recombination of photogenerated electron-hole pairs. The removal rate of 5 mg/L IOX by PC/PMS/Vis system reached 99.1% at 30 min, which was 2.0 times and 1.3 times higher than that of PA/PMS/Vis and PN/PMS/Vis system. The boosted oxidation activity with PC was due to the pH dependence of perylene diimide (PDI) self-assembly and the small amount of Cl− (0.56%) absorbed on PC, which can promote the transfer of electron-hole pairs, change the surface charge distribution and energy band position, and enhance π-electron conjugation. Based on density functional theory and electrostatic potential calculation, the Cl− adsorbed on the surface of PDI brings an effect on the electrostatic potential distribution. Furthermore, the built-in intermolecular electric field leads to accelerated charge transfer of PDI. In the PC/PMS/Vis system, holes, singlet oxygen and superoxide radical were perceived as the dominant contributors. The degradation of IOX carried out via pathways of amide hydrolysis, amino oxidation, hydrogen abstraction, deiodination reaction, and OH attack. This work provides a new method for the pollution control of IOX and scientific guidance for the tailored self-assembly of organic supramolecules.

Bimetal heterostructure NiCo2Se4 anode confined by carbon nano boxes for ultrafast and stable potassium storage

Transition metal selenides (TMSes) are regarded as promising anodes for potassium ion batteries (PIBs) benefit from their high theoretical capacity. However, the slow kinetics of potassium ion transport, poor charge transfer ability and short cycle life limit the development of transition metal selenide anode. In this article, the dice-shaped NiCo2Se4@N-doped carbon (NCS@NC) nanocomposite is designed for efficient and stable potassium storage. The in-situ formed carbon shell can not only act as a highly conductive framework to accelerate charge transfer, but also limit the volume fluctuation caused by the potassium ion repeated insertion/ extraction process. The in-situ and ex-situ characterization as well as theoretical calculation show that the heterogeneous interface formed by the heterogeneous metal species in NCS@NC spontaneously establish internal electric fields, which significantly accelerates the ion transport. As results, advanced NCS@NC anode with greatly enhanced electrochemical performance is obtained due to the synergy between the three-dimensional structure design and the heterogeneous interface strategy. NCS@NC anode displays extraordinary rate capacity (471.9 mAh g-1 at 2 A g-1) and ultralong cycle life at high current density (454.5 mAh g-1 at 2 A g-1 after 1000 cycles), which indicates that our modification strategy provides an alternative solution for designing advanced PIBs anodes.

Sonocatalytic degradation of tetracycline hydrochloride with CoFe2O4/g-C3N4 composite

In this work, different mass percent ratios of CoFe2O4 coupled g-C3N4 (w%-CoFe2O4/g-C3N4, CFO/CN) nanocomposites were integrated through a hydrothermal process for the sonocatalytic eradication of tetracycline hydrochloride (TCH) from aqueous media. The prepared sonocatalysts were subjected to various techniques to investigate their morphology, crystallinity, ultrasound wave capturing activity and charge conductivity. From the investigated activity of the composite materials, it has been registered that the best sonocatalytic degradation efficiency of 26.71 % in 10 min was delivered when the amount of CoFe2O4 was 25% in the nanocomposite. The delivered efficiency was higher than that of bare CoFe2O4 and g-C3N4. This enriched sonocatalytic efficiency was credited to the accelerated charge transfer and separation of e−-h+ pair through the S-scheme heterojunctional interface. The trapping experiments confirmed that all the three species i.e. •OH, h+ and •O2− were involved in the eradication of antibiotics. A strong interaction was shown up between CoFe2O4 and g-C3N4 in the FTIR study to support charge transfer as confirmed from the photoluminescence and photocurrent analysis of the samples. This work will provide an easy approach for fabricating highly efficient low-cost magnetic sonocatalysts for the eradication of hazardous materials present in our environment.

Ti3C2Tx-TiSe2 analogous heterostructure for flexible zinc ion battery

Exploring zinc-free anode materials is one of the effective strategies to get the zinc dendrites problem of flexible zinc ion battery (ZIB) solved. In this work, an analogous heterostructure (AHS) is constructed from the excellent MXene (Ti3C2Tx) and TiSe2 nanosheets. The AHS not only possesses numerous diffusion paths and Zn2+ storage sites but also possesses a stable conductive network to accelerate charge transfer in the electrode. As a collaborative advantage, electrochemical measurement results show that MXene/TiSe2 electrodes display an excellent specific capacity of 177.9 mAh g–1 at 0.10 A g–1 and a long-term cycling stability of 77.4 % capacity retention after 400 cycles. DFT computations further demonstrate the excellent performance of MXene/TiSe2 electrodes including desirable electronic conductivity and low Zn2+ migration barriers. The assembled flexible ZIB not only delivers a good specific capacity of 42.2 μAh cm−2 at 0.20 mA cm–2 and a competitive energy density of 37.4 μWh cm−2 but also exhibits excellent flexibility and thermostability. Furthermore, after 400 cycles at 0.60 A g−1, flexible ZIB shows a capacity retention of 73.8%. This work gives a successful attempt to design 2D layered materials as Zn metal-free anode for flexible ZIB.

Manganese cobalt sulfide/molybdenum disulfide nanowire heterojunction as an excellent bifunctional catalyst for electrochemical water splitting

Heterointerface engineering enhances catalytic active centers and charge transfer capabilities to increase oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) kinetics. In this study, a novel heterostructure of manganese cobalt sulfide-molybdenum disulfide on nickel foam (MnCo2S4-MoS2/NF) was synthesized via a two-step hydrothermal process. The nanowire-shaped MnCo2S4-MoS2 on NF displayed accelerated charge transfer ability and multiple integrated active sites. When tested in one molar (1 M) potassium hydroxide (KOH) electrolyte, it furnished low overpotentials of 105 and 171 mV for the HER and 220 and 300 mV for the OER at the current densities of 20 and 50 mA cm−2, respectively. An electrolyzer based on MnCo2S4-MoS2/NF required low operating potentials of 1.41 and 1.49 V to yield the current densities of 10 and 20 mA cm−2, respectively, surpassing commercial and previously reported catalysts. Density functional theory (DFT) analysis revealed that the MnCo2S4-MoS2 heterostructure possesses the optimal adsorption free energies for the reactants, an extended electroactive surface area, good charge transfer ability, and reasonable density of electronic states close to the Fermi level, all of which contribute to the high activity of catalyst. Thus, heterointerface engineering is a promising strategy for creating efficient catalysts for overall water splitting.

Insights into the synergy of platinum and nickel carbonate hydroxide for efficient methanol electro-oxidation

Pt-based nanostructures are an indispensable component in the anodic electrocatalysts of direct methanol fuel cells (DMFCs). Unfortunately, they often suffer from severe operational durability issues, due to CO poisoning. Here, a ternary hybrid consisting of Pt nanocrystals, ultrathin nanoflower-like nickel carbonate hydroxide (NiCH) and porous carbon is designed and fabricated to overcome this issue. Owing to the abundance of defects and large surface area of the NiCH, water molecules are easily dissociated to form OH adspecies, which could assist the oxidative removal of carbonaceous poisons from nearby Pt nanoparticles by the L-H mechanism. Porous carbon offsets the poor conductivity of NiCH and accelerates charge transfer. Impressively, this hybrid electrocatalyst could maintain over 39% of the initial activity after 5000 s of stability testing, and the MOR peak current was reduced by only 25% after 8000 CV cycles. CO stripping experiments demonstrate this incredible CO tolerance. DFT calculations further elucidate that the electronic interactions between H atom from NiCH and Pt downshifts the d-band center of Pt atom and accelerates the release of CO adsorbed on its surface. This work offers a promising candidate for the design of DMFCs anodic electrocatalysts.

Review on the Application of Semiconductor Heterostructures in Photocatalytic Hydrogen Evolution: State-of-the-Art and Outlook

Semiconductor materials, as the core of a system for collecting solar energy, possess excellent carrier separation efficiency and photochemical stability in the photocatalytic process. Single semiconductor materials as photocatalysts suffer from disadvantages such as low visible light absorption performance and quick photoelectron recombination rate. The photocatalytic efficiency can be significantly improved by constructing heterogeneous structures. In this review, the practical application of heterostructure semiconductor materials developed in recent years for photocatalytic hydrogen evolution in photocatalysis is described. Five kinds of semiconductor heterostructures commonly used in the field of photocatalytic hydrogen evolution are highlighted. Since the construction of nanomaterial heterostructures enhances photocatalytic activity, we describe in detail the fundamental understanding of the hydrogen evolution capabilities and principles of different photocatalysts. In particular, the effect of the formation of heterostructures on the hydrogen evolution ability in terms of enhanced visible light absorption and accelerated charge transfer is discussed. Finally, the challenges and prospects of the practical application of semiconductor heterostructures in photocatalytic hydrogen evolution are introduced. This review provides a reference for the study of photocatalytic semiconductor heterostructures.

Photo-Initiated in situ synthesis of polypyrrole Fe-Coated porous silicon microspheres for High-performance Lithium-ion battery anodes

A simple and environmentally friendly photoinitiated fabrication approach based on the photoelectric effect of semiconductor silicon is designed to synthesize yolk-shell like polypyrrole-iron coated porous silicon microspheres (PSi@PPy-Fe) as anode materials for LIBs. The polymerization of pyrrole monomers only occurs on the interface of silicon matrix where the vacancies are available, which effectively avoids the production of free PPy-Fe particles. XPS and first-principles calculations reveal that both the hydrogen-bond interaction and the covalent linkage are formed between Si and PPy-Fe layer, which is of great significance for maintaining good contact and strengthening the structure stability. It is demonstrated that the PPy-Fe coating may accelerate charge transfer and ion diffusion as well as prevent the Si-based materials peeling off from Cu collector. More importantly, the PPy-Fe coating could alleviate the violent structural expansion of Si anode, thus ameliorating the mechanical strength of the electrode. Consequently, the as-prepared yolk-shell like polypyrrole-iron coated porous silicon microspheres present outstanding cycling ability (1853.7 mAh/g after 200 cycles at 1 A/g) and superior rate capability (1558.4 mAh/g at 4 A/g). This work indicates that the photochemical modification strategy for Si may have a bright prospect in a wide range of fields.

Modulating microenvironment of active moiety in Prussian blue analogues via surface coordination to enhance CO2 photoreduction

Well-arranged photosensitive units and catalytic sites in closeness are critical for enhancing charge separation effectiveness and promoting photocatalysis. Here, a heterogeneous interface is constructed, which binds a deprotonated carboxyl group on perylene diimide (PDI) photosensitizer to unsaturated metal sites generated by etching of different Prussian blue analogues (PBAs). The atomically-dispersed metal sites and anchored photosensitive units greatly accelerate charge transfer. Typically, the S-scheme heterojunction built by etched NiCo PBA and PDI (NCSP) possesses bond of O-Ni. Density functional theory (DFT) and in-situ technology reveals the electron density of the Ni active site is optimized. Consequently, activation barrier of CO2 on the Ni site was reduced, thus improving the CO generation (60.0 μmol g−1) up to about 9 times than NiCo PBA. This work reveals key insights into the precise modulation of active moiety for efficient photocatalytic CO2 conversion.

In situ insight into the low-temperature promotion of ZIF-67 in electrocatalytic oxygen evolution reaction

An efficient electrocatalyst is crucial for sustainable hydrogen-fuel production, where cobalt oxyhydroxide is one of the most active catalysts for alkaline water splitting. Here, we designed a series of Co-based catalysts fabricated by direct low-temperature calcination of ZIF-67 for electrocatalytic oxygen evolution reaction (OER). Interestingly, the treatment of the pristine ZIF-67 by the temperature of only 200 °C was found to induce the most electroactive composition with a high electrochemically active surface of 373.5 cm2 and turnover frequency of 129.7 s−1, while a high specific surface area (1745 m2·g−1) is preserved. It resulted in a robust catalyst with a low overpotential of 317.8 mV at 10 mA·cm−2 and accelerated charge transfer, leading to improved performances in electrochemical energy conversion from water. Moreover, using in situ spectroscopy, XRD and microscopic techniques the active intermediates, for example, M-O, M-OH, and M-OOH were revealed and thus the exact mechanism of the reaction was proposed. Due to the formation of active species a lattice oxygen mechanism (LOM) was revealed.

0D/2D/3D ternary Au/Ti3C2/TiO2 photocatalyst based on accelerating charge transfer and enhanced stability for efficiently hydrogen production

The development of multi-components composited photocatalytic materials with strong interaction is a key approach to realize the spatial separation and fast transfer of charge carriers in H2 production. In this study, 2D layered Ti3C2 with –OH group was introduced to stabilize thiolate-protected Au clusters by strong electrostatic interaction and coupled with TiO2 nanoparticles to build a 0D/2D/3D ternary Au/Ti3C2/TiO2 photocatalyst for H2 evolution. In this composited material, Ti3C2 can serve as the electron transfer intermedium accelerating charge transfer from TiO2 to Au clusters. Au/Ti3C2/TiO2 shows excellent photocatalytic performance for H2 production (7989 μmol⋅g-1h−1), approximately 13.7 times higher than that of Au/TiO2. Photoluminescence spectra and photoelectrochemical results confirm that the introducing of layered Ti3C2 into ternary Au/Ti3C2/TiO2 material can markedly suppress the photogenerated charge recombination and thus enhance the charge separation efficiency. Moreover, after several cyclic reactions, Au/Ti3C2/TiO2 maintained a high stability and durability, indicating the strong interaction of Ti3C2 with Au and TiO2. This work not only highlights the significant role of MXene for the enhancement of photogenerated electron transfer, but also demonstrates a clearly objective to construct a suitable composited photocatalyst for H2 production.

Architecture and Kinetic Studies of Photocatalytic H2O2 Generation and H2 Evolution through Regulation of Spatial Charge Transfer via Z-Scheme Path over a (001) Facet Engineered TiO2@MXene/B-g-C3N4 Ternary Hybrid.

Spatial charge separation and migration are the critical shortcomings dominating the core energy conversion corridors of photocatalytic systems. Here, a biomimetic multi-interfacial architecture providing strong coupled interaction and rapid charge transmission for photostable and competent photocatalytic H2O2 production and H2 evolution is proposed. The triple-hybrid all-solid-state Z-scheme system was formed with the (001) facet exposed TiO2 nanosheets derived from MXene layers and B-g-C3N4 nanosheets (M/(001)TiO2@BCN) through an electrostatic self-assembly strategy with intimate electronic interaction due to Ti orbital modulation and proper stacking among the hybrids. The metallic and highly conductive MXene layers act as solid state electron mediators in the Z-scheme heterojunction that promote electron-hole separation and migration efficiency. Specifically, the MTBCN-12.5 composite provides optimum yield of H2O2 up to 1480.1 μmol h-1 g-1 and a H2 evolution rate of 408.4 μmol h-1 (with ACE 6.7%), which are 4 and 20 fold greater than the pristine BCN, respectively. The enhanced photocatalytic performance is systematically identified by the increased surface area, higher cathodic and anodic current densities of -1.01 and 2.27 mA cm-2, delayed charge recombination as supported by PL and EIS measurement, and excellent photostability. The Z-scheme charge transfer mechanism is validated by time-resolved photoluminescence (TRPL) analysis, cyclic voltametric analysis, and the radical trapping experiment as detected by PL analysis. This research marks a substantial advancement and establishes the foundation for future design ideas in accelerating charge transfer.

Boosting charge-transfer in tuned Au nanoparticles on defect-rich TiO2 nanosheets for enhancing nitrogen electroreduction to ammonia production

The electrocatalytic nitrogen reduction reaction (eNRR) to ammonia (NH3) has been recognized as an effective, carbon–neutral, and great-potential strategy for ammonia production. However, the conversion efficiency and selectivity of eNRR still face significant challenges due to the slow transfer kinetics and lack of effective N2 adsorption and activation sites in this process. Herein, we designed and fabricated defect-rich TiO2 nanosheets furnished with oxygen vacancies (OVs) and Au nanoparticles (Au/TiO2-x) as the electrocatalyst for efficient N2-fixing. The experimental results demonstrate that OVs act as active sites, which enable efficient chemisorption and activation of N2 molecules. The Au nanoparticles loaded on the OVs-rich TiO2 nanosheets not only accelerate charge transfer but also change the local electronic structure, thus enhancing N2 adsorption and activation. In this work, the optimal Au/TiO2-x electrocatalyst displays a considerable NH3 yield activity of 12.5 μg h−1 mgcat.-1 and a faradaic efficiency (FE) of 10.2 % at −0.40 V vs reversible hydrogen electrode (RHE). More importantly, the Au/TiO2-x exhibits a stable N2-fixing activity in cycling and it persists even after 80 h of consecutive electrolysis. Density functional theory (DFT) calculations reveal that the OVs serve as the active sites in TiO2, while Au nanoparticles are crucial for improving N2 chemisorption and lowering the reaction energy barrier by facilitating the charge transfer for eNRR with a distal hydrogenation pathway. This research offers a rational catalytic site design for modulating charge transfer of active sites on metal-supported defective catalysts to boost N2 electroreduction to NH3.

In situ growth of 1T-WS2 on ultrathin Ti3C2Tx as a hybrid cocatalyst for enhancing the photocatalytic activity of CdS

Accelerating charge transfer and separation is the core mission of promoting photocatalytic H2 production activity. Here, the hybrid cocatalyst Ti3C2Tx/1T-WS2 is synthesized by in situ growth of 1T-WS2 on the ultrathin Ti3C2Tx surface using a solvothermal method for enhancing the photocatalytic activity of CdS. The difference in CB potentials between CdS and 1T-WS2 results in the rapid migration of photogenerated electrons from CdS to 1T-WS2. More importantly, because of the intimate Schottky interfacial contact between Ti3C2Tx and 1T-WS2, the electrons on the 1T-WS2 further rapidly transfer to the surface of Ti3C2Tx, thereby enhancing the separation efficiency of photogenerated electrons. Compared with the single Ti3C2Tx (4.66 mmol∙g−1∙h−1) and 1T-WS2 (10.65 mmol∙g−1∙h−1), the hybrid Ti3C2Tx/1T-WS2 cocatalyst (12.39 mmol∙h−1∙g−1) has more excellent catalytic hydrogen evolution performance. The apparent quantum efficiency (AQE) Ti3C2Tx/1T-WS2/CdS at λ = 420 nm reaches 50.9%. This work is helpful to understand the mechanism of the hybrid cocatalyst to improve charge separation.

Non-concentrated electrolyte with weak anion coordination enables low Li-ion desolvation energy for low-temperature lithium batteries

Tailoring the lithium-ion solvation structure of ether-based electrolyte to accelerate charge transfer is of significance in low-temperature lithium batteries but remains largely unexplored. Herein, we propose a strategy based on carbonates mediating the anion coordination to realize cold-resistant electrolyte with superior kinetics and improved anodic stability. The combination of computational and experimental methods reveals that decreasing anions in the Li+-solvation structure reduces the desolvation energy of Li+ and enhances low-temperature performance. A formulated electrolyte composed of 0.5 M lithium tetrafluoroborate in hybrid solvent of tetrahydrofuran and trifluoropropylene carbonate features a high ionic conductivity of 0.45 mS cm−1 at − 90 °C and an ultra-low freezing point of − 133 °C. Furthermore, in such electrolyte, the LiNi0.8Co0.1Mn0.1O2 cathode can be reversibly cycled at low temperature of − 40 °C and delivers a considerable specific capacity of 108.5 mAh/g at − 90 °C.

Self-assembled multilayers direct a buffer interphase for long-life aqueous zinc-ion batteries

A self-assembled multilayer was used to homogenize ion flux and accelerate charge transfer through area-induced deposition effects and strong dipole moments. The molecular domains act as a buffer interphase to achieve long-term stability.

Porous Ni3Fe intermetallic compounds as efficient and stable catalysts for the hydrogen evolution reaction in alkaline solutions.

It is crucial to develop cost-effective novel non-noble metal catalysts with high activity and durability for large-scale industrial hydrogen production via water splitting. Here, based on a facile powder metallurgy method, Ni3Fe intermetallic electrodes with porous structures and controllable phases have been designed and fabricated by sintering mixed Ni and Fe powders under an Ar atmosphere. The effects of sintering temperature on the morphology, porous structure and phase composition of the intermetallic were studied. The resultant Ni3Fe-900 intermetallic electrode exhibits promising HER activity in alkaline electrolytes with an overpotential of 112 mV to drive a current density of 10 mA cm-2. Additionally, the Ni3Fe-900 intermetallic electrode shows good alkali corrosion resistance and stability in the HER process at a current density as high as 500 mA cm-2 for 24 h with no significant changes of the surface morphology, porous structure and phases. The efficient HER performance of the Ni3Fe-900 electrode is attributed to the unique intrinsic activity of the intermetallic electrode, increased accessible active sites originating from the porous structure and accelerated charge transfer. This work provides new insights into the design of electrocatalysts for industrial large-scale hydrogen production by water splitting.

Layered porous Mn0.18V2O5@C with manganese and carbon provided by a metal-organic framework precursor as a cathode material for aqueous zinc-ion batteries.

At present, vanadium-based cathodes for aqueous zinc-ion batteries (AZIBs) are limited by their slow reaction kinetics, poor electrical conductivity, and low capacity retention. To overcome these problems, here, we design a layered porous Mn0.18V2O5@C as the cathode material for AZIBs using a manganese-containing metal-organic framework as a template through a simple solvothermal method. Such an electrode delivers an excellent specific capacity (380 mA h g-1 at 0.1 A g-1) accompanied by superior cycling stability (about 85% capacity retention for 2000 cycles at 6 A g-1). The excellent electrochemical performance of Mn0.18V2O5@C is ascribed to the improved interface activity including smooth zinc ion transport, abundant ion reaction active sites and accelerated charge transfer resulting from the coordination of the porous structure, doped conductive carbon, and the stable channel structure derived from the pillar effect of doping manganese ions, preventing a premature collapse of the electrode structure. It is also revealed by structural evolution analysis that the residual zinc ions also combine with the original Mn0.18V2O5 to form a ZnxMnyV2O5 phase, which serves as an additional structural pillar and in the meantime, also participates in the following cycles. These favorable electrochemical results suggest that Mn0.18V2O5@C is a suitable cathode material for AZIBs.

Nanoflower-like high-entropy Ni-Fe-Cr-Mn-Co (oxy)hydroxides for oxygen evolution.

High-entropy materials (HEMs) have potential application value in electrocatalytic water splitting because of their unique alloy design concept and significant mixed entropy effect. Here, we synthesize a high-entropy Ni-Fe-Cr-Mn-Co (oxy)hydroxide on nickel foam (NF) by a solvothermal method. The flower-like structure of FeNiCrMnCoOOH/NF can provide abundant active sites, thus improving the oxygen evolution reaction (OER) activity. In 1 M KOH, the FeNiCrMnCoOOH/NF shows an ultra-low overpotential (η10) of 201 mV for the OER, superior to FeNiCrMnAlOOH/NF, FeNiCrMnCuOOH/NF, FeNiCrMnMoOOH/NF, and FeNiCrMnCeOOH/NF. In addition, it exhibits a low η10 of 223 mV in 0.5 M NaCl + 1 M KOH and excellent stability. Electrochemical impedance spectroscopy measurements indicate that the synergistic effect between multiple metals accelerates charge transfer, while in situ Raman measurements reveal that NiOOH is a key active species for the OER. This work is of great significance for the construction of high-entropy (oxy)hydroxides for seawater electrolysis.