Alkaline Water Research Articles

Electrocatalytic properties of transition metal vanadates (T = Ti, Cr, Mn, & Fe) for overall water splitting

In this work, first row transition metal vanadates (TMVs), including titanium vanadate (TiV), chromium vanadate (CrV), manganese vanadate (MnV), and iron vanadate (FeV), were synthesized and investigated their electrocatalytic performance for the alkaline water splitting. The prepared TMVs showed easy electron transfer characteristics and tunable band structures, and among these TMVs, the synthesized FeV demonstrated the best electrocatalytic bifunctional activities for both HER (η100 = 375 mV) and OER (η100 = 260 mV) with a significant electronic and morphological stability over 100 h operation. The examination of electronic structure revealed that the balanced catalyst-intermediate interaction through optimum d-p orbital hybridization in FeV, adhering to the Sabater principle, vouched for such facile redox reaction. The structural stability might be attributed to the synergism between iron and vanadate as the multivalent Fe adjusted the shift in vanadium coordination when the oxidation state of Vn+ (n = 3–5) changed. Moreover, the two-electrode system of FeV || FeV in a single electrolyzer demonstrated superior cell voltage100 of 1.86 V in comparison to commercial Pt/C || IrO2 electrodes (1.91 V). This work offers facile perspective to produce TMVs as the efficient electrocatalysts for green synthesis of fuel gases.

In-situ realtime study of zinc selenide nanoparticles sustained by polypyrrole in alkaline water oxidation

Interest in metal electrodeposition for synthesizing customized nanomaterials has resurged, particularly for applications such as sensors and fuel cells. The present study involved the synthesis of ZnSe nanoparticles (via hydrothermal method) while polypyrrole and novel composite Ppy@ZnSePpy@Ppy (via sequential electrodeposition technique) on a glassy carbon (GC) electrode and their physiochemical, electrochemical, and operando spectro-electrochemical characterizations towards oxygen evolution reaction (OER). Results indicated that ZnSe nanoparticles are well embedded within the Ppy layers and during OER the composite electrocatalyst approached 398 mV at 10 mA cm−2 and exhibited Tafel value (b ∼ 75 mV dec−1) with ECSA (0.03) which shows better results than other two. In addition, the operando spectro-electrochemical spectra of the composite revealed the significant generation of active intermediate oxygen species of selenium and Zn2+. The important feature of the current work is the disclosure of Se's questionable role and species involved in OER found to be Se4+.

Induction heating boosts water splitting on iron-coated nickel foam

Abstract Alkaline water electrolysis at high temperatures can rival acidic proton-exchange membranes.
However, they suffer from increased energy consumption, reduced lifespan of materials and heightened safety risks. Magnetic hyperthermia is a method of localizing intense heating in the presence of an external high-frequency alternating magnetic field. In this study, we developed a custom electromagnetic induction device capable of generating a small magnetic field of about 2 µT. High-permeability nickel foam is used as electrodes. Results show that the iron coated nickel foam decreases the overpotential of the hydrogen evolution reaction and oxygen evolution reaction by ~150 mV and 60 mV, respectively, at 20 mAcm−2 when subjected to magnetic heating in a high-frequency alternating magnetic field. The overall water splitting current of Ni foam/Fe increases 540% under intermittent induction. The enhanced stability of Ni foam/Fe is attributed to the high binding energy of metal-O on the surface. The density function theory calculations further indicates that the lattice expansion of the metal electrode under induction heating optimizes the adsorption and desorption of H*, thereby enhancing the HER performance.

Dynamic Simulation and Performance Analysis of Alkaline Water Electrolyzers for Renewable Energy-Powered Hydrogen Production

This paper presents a comprehensive study on the dynamic simulation modeling of alkaline water electrolyzers. Detailed experimental testing and characteristic analysis reveal that alkaline water electrolyzers have long startup times, rapid dynamic responses, and poor dynamic stability. These characteristics are critical for the development of accurate models and effective strategies. A dynamic simulation model was established in MATLAB R2022b and Simulink, enabling standalone simulation operation and module encapsulation. This model facilitates the construction of hydrogen production clusters and serves as a foundational tool for system strategy research. Simulations of rated current loading and unloading for four electrolyzers over 6 h showed significant differences in startup and operation. Key parameters such as cell voltage, maximum loadable power, hydrogen production efficiency, and energy consumption were analyzed. Temperature simulations indicated significant differences in thermal equilibrium points and cooling modes among the electrolyzers, as determined by structural design and cooling system efficiency. These findings highlight the need for efficiency improvements in high-current density electrolyzers. Overall, the model effectively represents commercial electrolyzer characteristics and offers a reliable tool for future research on control strategies for adapting hydrogen production systems to renewable energy power fluctuations, laying a solid foundation for the optimization of electrolyzer design and operation strategies.

Thermodynamic and Economic Analysis of the Green Ammonia Synthesis System Driven by Synergistic Hydrogen Production Using Alkaline Water Electrolyzers and Proton Exchange Membrane Electrolyzers

Green ammonia and hydrogen from renewable energy sources have emerged as crucial players during the transition of the chemical industry from a fossil energy‐dominated economy to one that is environmentally friendly. This work proposes a green ammonia synthesis system driven by synergistic hydrogen generation using alkaline water electrolyzers (AWE) and proton exchange membrane electrolyzers (PEMEC). The effects of hydrogen‐production ratios of PEMEC and AWE on the thermodynamic and economic performance of the system are compared and analyzed via multi‐objective optimization. The findings showed that an increase in the amount of hydrogen produced by PEMEC improves the system's energy efficiency, but the payback period is delayed because of the PEMEC high initial investment cost. The techno‐economic performance of the system at a 1:1 ratio of PEMEC to AWE hydrogen production are investigated considering the system level heat integration based on the pinch point analysis method to maximize the heat recovery. The results show that increasing the operational temperature, the pressure of the electrolyzer, and the ammonia synthesis pressure will enhance the system's thermal performance. Economic analysis shows that reducing electricity prices and electrolyzer investment costs will be the key to achieving the economic feasibility of the green ammonia system.

Developing a European aquatic macrophyte transfer function for reconstructing past lake-water chemistry

Quantitative paleoecological reconstructions using biological proxies, such as diatoms, Cladocera, and chironomids, have revolutionized paleolimnology and have greatly contributed to the understanding of the past local and regional environmental changes, as well as to nature conservation. While macrophytes are good ecological indicators, they have rarely been used to reconstruct past lake-water chemistry. The present study investigates which environmental variable best explains aquatic plant community composition in Finnish, Polish, and Swedish lakes for its further use in quantitative paleoenvironmental reconstructions. The method involved the creation of a modern macrophyte-environment calibration dataset, calculation of modern calibration functions using simple averaging regression, and final reconstruction of past environmental conditions in Lake Linówek (NE Poland) from a fossil assemblage using weighted averaging calibration. The data demonstrate that conductivity and alkalinity best explained macrophyte community composition in our dataset. Species “optima” for alkalinity were influenced by the presence/absence of carbon concentrating mechanisms (CCMs), enabling the utilization of HCO3− as a carbon source. Quantitative paleoenvironmental reconstruction indicates that past water conductivity and alkalinity fluctuated depending on internal lake processes and the supply of basic ions to the lake from the catchment related to climate and soil development in the watershed during the late Glacial (∼14,500–11,700 calibrated years before the present; cal BP) and the Holocene (11,700 cal BP–recent). We conclude that macrophytes can be successfully used for past lake-water chemistry reconstruction. Furthermore, calculated modern calibration functions for conductivity and alkalinity can be used in nature conservation for determining habitat requirements of numerous endangered macrophyte species as a basis for successful (re)introductions.

Construction of Ru/MnO–Mn7C3/N-doped carbon sheets for boosting electrocatalytic hydrogen generation

Suffering from their low conductivity, Mn-base oxides are commonly inactive in H–OH activation. Generally, tailoring the coordinate environment of materials could induce variation in the atomic arrangement and further influence their chemical activity. Herein, we propose a feasible strategy to mediate the electronic structure of Mn-based oxides by facile hydrothermal method and thermal reduction route. Compared with MnO2 sheets, the as-synthesized Ru/MnO–Mn7C3/N-doped carbon sheets (Ru/MnO–Mn7C3/NC) exhibit the higher activity for both acidic (73 mV) and alkaline water reduction reaction (44 mV@10 mA/cm2). Benefitting from unique structures, Ru/MnO–Mn7C3/NC sheets show the better freshwater/seawater oxidation reactivity, exceeding RuO2. The strong interaction of MnO–Mn7C3 heterostructures, Ru, and N-doped carbon endows Ru/MnO–Mn7C3/NC with the good freshwater and seawater dissociation performance, outperforming most of the reported Mn-based oxides.

Effects of Alkalinity Stress on Amino Acid Metabolism Profiles and Oxidative-Stress-Mediated Apoptosis/Ferroptosis in Hybrid Sturgeon (Huso dauricus ♀ × Acipenser schrenckii ♂) Livers

Alkaline water is toxic to cultured aquatic animals that frequently live in pH-neutral freshwater. Overfishing and habitat destruction have contributed to the decline in the wild sturgeon population; consequently, the domestic hybrid sturgeon has become an increasingly important commercial species in China. Hybrid sturgeons are widely cultured in alkaline water, but little is known about the effects of alkalinity stress on hybrid sturgeon liver tissues. We exposed hybrid sturgeons to four alkaline concentrations (3.14 ± 0.02 mmol/L, 7.57 ± 0.08 mmol/L, 11.78 ± 0.24 mmol/L and 15.46 ± 0.48 mmol/L). Histopathology, biochemical index assessment, gene expression level detection and metabolomics analysis were used to investigate the negative effects on liver functions following exposure to NaHCO3. Livers exposed to alkaline stress exhibited severe tissue injury and clear apoptotic characteristics. With increased exposure concentrations, the hepatic superoxide dismutase, catalase, glutathione peroxidase and alkaline phosphatase activities significantly decreased in a dose-dependent manner. NaHCO3 exposure up-regulated the transcriptional levels of apoptosis/ferroptosis-related genes in livers. Similarly, the expression trends of interleukin-1β and heat shock protein genes also increased in high-alkalinity environments. However, the expression levels of complement protein 3 significantly decreased (p < 0.05). Hepatic untargeted metabolomics revealed the alteration conditions of various metabolites associated with the antioxidant response, the ferroptosis process and amino acid metabolism (such as beta-alanine metabolism; alanine, aspartate and glutamate metabolism; and glycine, serine and threonine metabolism). These data provided evidence that NaHCO3 impaired immune functions and the integrity of hybrid sturgeon liver tissues by mediating oxidative-stress-mediated apoptosis and ferroptosis. Our results shed light on the breeding welfare of domestic hybrid sturgeons and promote the economic development of fisheries in China.

Quaternary layered double hydroxides from spent battery as electrocatalysts for the oxygen evolution reaction

Quaternary layered double hydroxides (LDHs) are emerging as effective oxygen evolution reaction (OER) electrocatalysts for alkaline water splitting. In this work, NiCoMnFe-LDH has been successfully fabricated using leachate from recycled battery cathodes, demonstrating a sustainable approach to resource utilization. By incorporating varying amounts of Vulcan XC72 carbon as a support, we improved the conductivity of the NiCoMnFe-LDH. Our results indicate that the addition of Vulcan XC72 enhances the electrocatalytic performance of the nanocomposites. Notably, the NiCoMnFe-LDH/C-50 sample exhibited superior OER activity, with an overpotential of 329 ± 10 mV at a current density of 10 mA cm⁻2 and stable performance over 15 h. Detailed characterization confirmed the advantages of the carbon support in improving both the structural stability and catalytic efficiency. This work may pave the way to a sustainable method for repurposing spent battery cathodes, advancing the development of cost-effective and environmentally friendly electrocatalysts for clean energy applications.

Elucidating the increased ohmic resistances in zero-gap alkaline water electrolysis

This study investigates the increased ohmic resistances observed in zero-gap alkaline water electrolyzers, aiming to provide insights that can help enhance electrolyzer efficiency and enable operation at higher current densities. Electrochemical impedance spectroscopy (EIS) has been employed in combination with chronopotentiometry, utilizing a custom-designed flow cell with nickel perforated electrodes and a Zirfon UTP 500 diaphragm. Observed differences in area-ohmic resistance values obtained through I-V fitting and EIS, are ascribed to a non-linear Tafel slope at higher current densities. Ohmic resistance values measured with EIS are up to 27% higher than the ex-situ determined value, a significantly smaller percentage than expected based on previous studies. The presence of bubbles outside and inside the diaphragm is identified as the key factor contributing to this increased resistance. We recommend the use of an improved fitting approach, accounting for non-linear Tafel behavior, and the use of a 4-terminal configuration when performing EIS measurements to minimize cable and contact resistance.

Computational Fluid Dynamics Analysis of Gas Crossover in an Alkaline Electrolyzer Using a Multifluid Model

A comprehensive three-dimensional, two-phase isothermal model is developed for an alkaline water electrolyzer, aimed to accurately simulate complex interactions at gas-liquid interfaces, ion transport mechanisms, and electrochemical reactions. The present model accounts for the local volume fraction of gas, the species spatial distributions and both electrical and electrolyte potentials. The crossover of the product gases is a result of diffusion of the dissolved species in the liquid phase. This work explores the role of parameters such as mass transfer coefficients and supersaturation within the cell. Despite the model demonstrating trends that are consistent with anticipated physical behaviors, it currently tends to underestimate the crossover effect.

Biology-Based Synthesis of Nickel Single Atoms on the Surface of Geobacter sulfurreducens as an Efficient Electrocatalyst for Alkaline Water Electrolysis.

Single-atom metal catalysts are promising electrocatalysts for water electrolysis. Nickel-based electrocatalysts have shown attractive application prospects for water electrolysis. However, synthesizing stable Ni single atoms using chemical and physical approaches remains a practical challenge. Here, a facile and precise method for synthesizing stable nickel single atoms on the surface of Geobacter sulfurreducens using a microbial-mediated extracellular electron transfer (EET) process is demonstrated. It is shown that G. sulfurreducens can effectively anchor nickel single atoms on their surface. X-ray absorption near-edge structure and Fourier-transformed extended X-ray absorption fine structure spectroscopy confirm that the nickel single atom is coordinated to nitrogen in the cytochromes. The as-synthesized nickel single atoms on G. sulfurreducens exhibit excellent bifunctional catalytic properties for alkaline water electrolysis with low overpotential (η) to achieve current density (10mAcm-2) for both hydrogen evolution reactions (η = 80mV) and oxygen evolution reaction (η = 330mV) with minimal catalyst loading of 0.0015mgNicm-2. The nickel single-atom catalyst shows long-term stability at a constant electrode potential. This synthesis method based on the EET capability of electroactive bacteria provides a simple and scalable approach for producing low-cost and highly efficient nonnoble transition metal single-atom catalysts for practical applications.

Frequency response coefficient optimal allocation strategy for multi-stacks alkaline water electrolyzer plant

Currently, power discrepancies between stacks are often overlooked when developing frequency response (FR) strategies for multi-stack alkaline water electrolyzer plants (AWEPs), which limits the full utilization of the plant’s FR potential. To address this issue, this paper introduces a stack-level FR coefficient allocation strategy aimed at minimizing post-contingency frequency deviation. Specifically, the quantitative relationship between the operating power of alkaline water electrolyzer (AWE) stacks and steady-state frequency deviation is first derived, followed by the formulation of an optimal FR problem. The solution to this problem is an FR strategy based on the principle of equal frequency deviation, which optimally allocates FR coefficients among AWE stacks according to their operating power, thereby maximizing the plant’s FR support capacity. Equivalent circuit model-based case study demonstrates that, compared to existing strategies, the proposed approach achieves a more balanced power distribution among the stacks during the FR process. This even power allocation not only reduces post-contingency frequency deviation but also enhances productivity and streamlines production management in the AWEP, thereby increasing the plant owner’s willingness to participate in FR. Specifically, the proposed strategy results in a 29.3% reduction in post-contingency frequency deviation, a 1.8% improvement in production efficiency under a 10 MW power imbalance, a 2.3% increase in hydrogen production rate under a 4 MW power imbalance, and more stable operation under a 16 MW power imbalance.

Improving Heat Transfer Efficiency in Shell-and-Tube Heat Exchangers through the Incorporation of Alkaline Water Nanofluids

Improving Heat Transfer Efficiency in Shell-and-Tube Heat Exchangers through the Incorporation of Alkaline Water Nanofluids

Designing Bifunctional Electrocatalysts Based on Complex Cobalt-Sulfo-Boride Compound for High-Current-Density Alkaline Water Electrolysis.

In the quest to harness renewable energy sources for green hydrogen production, alkaline water electrolysis has emerged as a pivotal technology. Enhancing the reaction rates of overall water electrolysis and streamlining electrode manufacturing necessitate the development of bifunctional and cost-effective electrocatalysts. With this aim, a complex compound electrocatalyst in the form of cobalt-sulfo-boride (Co-S-B) was fabricated using a simple chemical reduction method and tested for overall alkaline water electrolysis. A nanocrystalline form of Co-S-B displayed a combination of porous and nanoflake-like morphology with a high surface area. In comparison to Co-B and Co-S, the Co-S-B electrocatalyst exhibits better bifunctional characteristics requiring lower overpotentials of 144 mV for hydrogen evolution reaction and 280 mV for oxygen evolution reaction to achieve 10 mA/cm2 in an alkaline electrolyte. The improved Co-S-B performance is attributed to the synergistic effect of sulfur and boron on cobalt, which was experimentally confirmed through various material characterization tools. Tafel slope, electrochemical surface area, turnover frequency, and charge transfer resistance further endorse the active nature of the Co-S-B electrocatalyst. The robustness of the developed electrocatalyst was validated through a 50 h chronoamperometric stability test, along with a recyclability test involving 10,000 cycles of linear sweep voltammetry. Furthermore, Co-S-B was tested in an alkaline zero-gap water electrolyzer, reaching 1 A/cm2 at 2.06 V and 60 °C. The significant activity and stability demonstrated by the cobalt-sulfo-boride compound render it as a promising and cost-effective electrode material for commercial alkaline water electrolyzers.

Upcycling of Spent LiFePO4 Cathodes to Heterostructured Electrocatalysts for Stable Direct Seawater Splitting.

The pursuit of carbon-neutral energy has intensified the interest in green hydrogen production from direct seawater electrolysis, given the scarcity of freshwater resources. While Ni-based catalysts are known for their robust activity in alkaline water oxidation, their catalytic sites are prone to rapid degradation in the chlorine-rich environments of seawater, leading to limited operation time. Herein, we report a Ni(OH)2 catalyst interfaced with laser-ablated LiFePO4 (Ni(OH)2/L-LFP), derived from spent Li-ion batteries (LIBs), as an effective and stable electrocatalyst for direct seawater oxidation. Our comprehensive analyses reveal that the PO4 3- species, formed around L-LFP, effectively repels Cl- ions during seawater oxidation, mitigating corrosion. Simultaneously, the interface between in situ generated NiOOH and Fe3(PO4)2 enhances OH- adsorption and electron transfer during the oxygen evolution reaction. This synergistic effect leads to a low overpotential of 237 mV to attain a current density of 10 mA cm-2 and remarkable durability, with only a 3.3 % activity loss after 600 h at 100 mA cm-2 in alkaline seawater. Our findings present a viable strategy for repurposing spent LIBs into high-performance catalysts for sustainable seawater electrolysis, contributing to the advancement of green hydrogen production technologies.

Upcycling of Spent LiFePO4 Cathodes to Heterostructured Electrocatalysts for Stable Direct Seawater Splitting

AbstractThe pursuit of carbon‐neutral energy has intensified the interest in green hydrogen production from direct seawater electrolysis, given the scarcity of freshwater resources. While Ni‐based catalysts are known for their robust activity in alkaline water oxidation, their catalytic sites are prone to rapid degradation in the chlorine‐rich environments of seawater, leading to limited operation time. Herein, we report a Ni(OH)2 catalyst interfaced with laser‐ablated LiFePO4 (Ni(OH)2/L‐LFP), derived from spent Li‐ion batteries (LIBs), as an effective and stable electrocatalyst for direct seawater oxidation. Our comprehensive analyses reveal that the PO43− species, formed around L‐LFP, effectively repels Cl− ions during seawater oxidation, mitigating corrosion. Simultaneously, the interface between in situ generated NiOOH and Fe3(PO4)2 enhances OH− adsorption and electron transfer during the oxygen evolution reaction. This synergistic effect leads to a low overpotential of 237 mV to attain a current density of 10 mA cm−2 and remarkable durability, with only a 3.3 % activity loss after 600 h at 100 mA cm−2 in alkaline seawater. Our findings present a viable strategy for repurposing spent LIBs into high‐performance catalysts for sustainable seawater electrolysis, contributing to the advancement of green hydrogen production technologies.

Coaggregation Occurs between a Piliated Unicellular Cyanobacterium, Thermosynechococcus, and a Filamentous Bacterium, Chloroflexus aggregans.

Cyanobacteria are widely distributed in natural environments including geothermal areas. A unicellular cyanobacterium, Thermosynechococcus, in a deeply branching lineage, develops thick microbial mats with other bacteria, such as filamentous anoxygenic photosynthetic bacteria in the genus Chloroflexus, in slightly alkaline hot-spring water at ~55 °C. However, Thermosynechococcus strains do not form cell aggregates under axenic conditions, and the cells are dispersed well in the culture. In this study, Thermosynechococcus sp. NK55a and Chloroflexus aggregans NBF, isolated from Nakabusa Hot Springs (Nagano, Japan), were mixed in an inorganic medium and incubated at 50 °C under incandescent light. Small cell aggregates were detected after 4 h incubation, the size of cell aggregates increased, and densely packed cell aggregates (100-200 µm in diameter) developed. Scanning electron microscopy analysis of cell aggregates found that C. aggregans filaments were connected with Thermosynechococcus sp. cells via pili-like fibers. Co-cultivation of C. aggregans with a pili-less mutant of Thermosynechococcus sp. did not form tight cell aggregates. Cell aggregate formation was observed under illumination with 740 nm LED, which was utilized only by C. aggregans. These results suggested that Chloroflexus filaments gather together via gliding motility, and piliated cyanobacterial cells cross-link filamentous cells to form densely packed cell aggregates.

Decoupling Electrolytic Water Splitting by an Oxygen-Mediating Process.

Decoupled water electrolysis systems, incorporating a reversible redox mediator that allows for the construction of membrane-free electrolyzers, have emerged as a promising approach to produce high-purity hydrogen with remarkable flexibility. The key factor crucial for practical applications lies in the development of mediator electrodes that possess suitable redox potential, high redox capacity, excellent cycling reversibility and stability. Herein, we introduce a novel concept of oxygen-mediating redox mediators (ORMs) employing Bi2O3 as an example material, which are capable of sequestering oxygen during the hydrogen evolution reaction and subsequently releasing it to generate oxygen gas under alkaline conditions. Thanks to its remarkable reversible redox activity and specific capacity, the Bi2O3 electrode boasts an impressive reversible specific capacity of 300.8 mA h g-1 and delivers outstanding cycling performance for >1000 cycles at a current density of 2.0 A g-1. Furthermore, the implementation of such a decoupled alkaline water electrolysis system can be integrated with a Bi2O3-Zn battery, enabling both power-to-fuel (hydrogen production) and chemical-to-power (rechargeable Bi2O3-Zn battery) conversion. With many oxygen-carrier materials readily available and the potential integration with rechargeable alkaline batteries, this study provides an alternative competitive route for membrane-free decoupled water splitting through the oxygen-mediating mechanism with combined energy transformation and storage.

Clustered VCoCOx Nanosheets Anchored on MXene–Ti3C2@NF as a Superior Bifunctional Electrocatalyst for Alkaline Water Splitting

Ti3C2, one typical MXene, has great potential to be coupled with various transition metals. Herein, a novel and effective catalyst is developed by synergistically loading VCoCOx onto Ti3C2‐modified nickel foam (VCoCOx–Ti3C2@NF). Field emission scanning electron microscope and high‐resolution transmission electron microscopy are employed to characterize the morphology and structure. As expected, the catalyst optimized by response surface methodology attains overpotentials of 290 and 64 mV and Tafel slopes of 82 and 79 mV dec−1 for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively. By using the bifunctional VCoCOx–Ti3C2@NF catalyst, the water splitting current density achieves 10 mA cm−2 in 1.0 mol L−1 KOH electrolyte at cell voltage of 1.52 V, comparable with the noble metal electrolyzer Pt@C@NF||RuO2@NF (1.57 V). Furthermore, the resulting catalyst exhibits excellent cycling durability after 120 h of continuous catalysis, which retains 103.8% and 105.4% of potential (V vs reversible hydrogen electrode) for OER and HER, respectively. Density functional theory calculation reveals that the Gibbs free energy barriers for the OER and HER intermediates are reduced due to the integration of VCoCOx with Ti3C2@NF. The fabricated VCoCOx–Ti3C2@NF catalyst is a promising electrochemical material for clean energy production.