Porous Co2P film coated on carbon fiber as highly performance electrocatalyst toward overall water splitting

Designing porous active materials and enhancing their contact with conductive substrates is an effective strategy to improve electrolytic water splitting performance of noble metal-free catalysts. Herein, a facile nanostructured electrode, composed of porous Co₂P films coated on carbon fiber (CF@P–Co₂P), is designed and prepared. The unique three-dimensional interconnected pore structure of Co₂P and the close contact between porous Co₂P and CF not only increase specific surface areas to expose abundant catalytic sites but also stimulate the transport of electron, mass and gaseous products in catalytic process. Benefit from the reasonable electrode structure, the self-supported CF@P–Co₂P electrodes present perfect performance with only needing overpotentials of 107.7/175.5/141.8 mV for hydrogen evolution reaction (HER) in acidic/neutral/alkaline solution and 269.4 mV for oxygen evolution reaction (OER) in alkaline solution to get current density of 20 mA cm^?2. In addition, alkaline electrolyzer equipped with CF@P–Co₂P bifunctional electrodes only needs a cell voltage of 1.657 V to get water-splitting current density of 20 mA cm^?2. Even better, the electrolyzer can continuously electrolyze over 50 h with negligibly decreasing current density and the Faraday efficiency is close to 100% toward both HER and OER.     

Combustion-derived BaNiO3 nanoparticles as a potential bifunctional electrocatalyst for overall water splitting

Electrochemical water electrolyser though an assuring solution for clean hydrogen production, the sluggish kinetics and high cost of existing precious metal electrocatalyst remains a barrier to its effective utilization. Herein, solution combustion route derived perovskite type barium nickelate (BaNiO₃) nanoparticles were developed and studied for their bifunctional electrocatalytic properties towards overall water splitting. The unannealed BaNiO₃ nanoparticles exhibited the highest OER and HER activity with overpotentials 253 mV and 427 mV respectively to attain 10 mAcm⁻² in 1.0 M KOH. Using unannealed BaNiO₃ as a bifunctional electrocatalyst in a two-electrode alkaline electrolyser, the cell was able to achieve the benchmark current density at a low cell voltage of 1.82 V. Impressively the setup's electrocatalytic performance improved 4.9% after continuous overall water splitting for 24 h at 30 mAcm⁻². Therefore, BaNiO₃ nanoparticles can be a low-cost and efficient alternative for noble metal electrocatalysts for clean H₂ production.     

Bimetallic-metal organic framework-derived Ni3S2/MoS2 hollow spheres as bifunctional electrocatalyst for highly efficient and stable overall water splitting

Herein, strongly coupled Ni₃S₂/MoS₂ hollow spheres derived from NiMo-based bimetal-organic frameworks are successfully synthesized for overall water splitting via a one-pot solvothermal method followed by sulfurization. A well-defined hollow spherical structure with a heterointerface between Ni₃S₂ and MoS₂ is constructed using solvothermal and sulfurization processes. Owing to their bimetallic heterostructure, porous hollow carbon structure with large surface area, and numerous exposed active sites, the Ni₃S₂/MoS₂ hollow spheres are found to be efficient electrocatalysts for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). The heterostructured Ni₃S₂/MoS₂ hollow spheres show small overpotentials of 303 and 166 mV to reach a current density of 10 mA cm^?2 for the OER and HER in 1.0 M KOH, respectively. Furthermore, an overall water-splitting electrolyzer consisting of the Ni₃S₂/MoS₂ hollow spheres as both the anode and cathode requires a very low cell voltage of 1.62 V to drive a current density of 10 mA cm^?2 with outstanding long-term stability for 100 h. Our findings offer a new pathway for the design and synthesis of electrochemically advanced bifunctional catalysts for various energy storage and conversion applications.     

N,S co-doped NiCo2O4@CoMoO4/NF hierarchical heterostructure as an efficient bifunctional electrocatalyst for overall water splitting

Electrocatalytic overall water splitting technology has received considerable attention in recent years. The fabrication of low-cost, earth-rich and potent bifunctional electrocatalysts is vital for hydrogen evolution (HER) and oxygen evolution reactions (OER). Herein, the N and S co-doped NiCo₂O₄@CoMoO₄ heterostructures (N, S–NCO@CMO₄₀₀) are fabricated by CVD and hydrothermal methods. N and S atoms as auxiliary active centers can increase the activity of Ni, Co and Mo atoms at the same time. Hierarchical heterostructures generate more interfaces to accelerate mass transfer and enlarge the electrochemical surface area, which greatly enhances the catalytic activity. The catalyst displays outstanding OER performance. The overpotentials of OER and HER are 165 and 100 mV at a current density of 10 mA cm^?2, respectively. More importantly, the N, S–NCO@CMO₄₀₀-based water splitting cell has a low voltage of 1.46 V at 10 mA cm^?2. Furthermore, the N, S–NCO@CMO₄₀₀ runs for 120 h in stable operation. This work provides new ideas for the design of hierarchical heterostructures with two-element incorporation.     

Electronic regulation and core-shell hybrids engineering of palm-leaf-like NiFe/Co(PO3)2 bifunctional electrocatalyst for efficient overall water splitting

Constructing efficient and stable bifunctional electrocatalysts for overall water splitting remains a challenge because of the sluggish reaction kinetics. Herein, the core-shell hybrids composed of Co(PO₃)₂ nanorod core and NiFe alloy shell in situ grown on nickel foam (NiFe/Co(PO₃)₂@NF) are synthesized. Owing to the hierarchical palm-leaf-like structures and strong adhesion between NiFe alloys, Co(PO₃)₂ and substrates, the catalyst provides a large surface area and rapid charge transfer, which facilitates active sites exposure and conductivity enhancement. The interfacial effect in the NiFe/Co(PO₃)₂ core-shell structure modulates the electronic structure of the active sites around the boundary, thereby boosting the intrinsic activity. Benefiting from the stable structure, the durability of the catalyst is not impaired by the inevitable surface reconfiguration. The NiFe/Co(PO₃)₂@NF electrode presents a low cell voltage of 1.63 V to achieve 10 mA cm^?2 and manifests durability for up to 36 h at different current densities.     

Co-based MOF-derived Co/CoN/Co2P ternary composite embedded in N- and P-doped carbon as bifunctional nanocatalysts for efficient overall water splitting

In this work, we developed ternary metallic cobalt-cobalt nitride-dicobalt phosphide composite embedded in nitrogen and phosphorus co-doped carbon (Co/CoN/Co₂P-NPC) as bifunctional catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The as-prepared Co/CoN/Co₂P-NPC is achieved by simultaneous annealing and phosphating of a Co–N rich metal-organic frameworks (MOFs) precursor. Compare with the phosphorus-free Co/CoN embedded nitrogen-doped carbon electrocatalyst (Co/CoN-NC), the as-prepared Co/CoN/Co₂P-NPC display superior HER and OER low overpotential of 99 mV and 272 mV at current density of 10 mA cm⁻². When Co/CoN/Co₂P-NPC electrocatalyst is use as bifunctional catalysts in overall alkaline water splitting, it exhibit excellent behaviour with 10 mA cm⁻² current at overall cell potential of 1.60 V. The excellent performance of Co/CoN/Co₂P-NPC electrocatalyst is attributed to the phosphating process that could further enhance synergistic effect, create stronger electronic interactions, and form efficient dual heteroatom doping to optimize the interfacial adhesion within the electrocatalyst. This present work will create more opportunities for the development of new, promising and more active sites electrocatalysts for alkaline electrolysis.     

Tungsten promoted nickel phosphide nanosheets supported on carbon cloth: An efficient and stable bifunctional electrocatalyst for overall water splitting

It is of great significance to develop a highly active, durable and inexpensive bifunctional electrocatalyst for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we report a tungsten-doped nickel phosphide nanosheets based on carbon cloth (W–Ni₂P NS/CC) as an efficient bifunctional catalyst through simple hydrothermal and phosphorization for overall water splitting in 1 M KOH. The W–Ni₂P NS/CC exhibits excellent electrochemical performance with low overpotentials for HER (η₁₀ = 71 mV, η₅₀ = 160 mV) and OER (η₂₀ = 307 mV, η₅₀ = 382 mV) in 1 M KOH, as well as superior long-term stability. Moreover, W–Ni₂P NS/CC as a bifunctional catalyst reveals remarkable activity with a low voltage of 1.55 V to reach a current density of 20 mA cm⁻². This work provides a viable bifunctional catalyst for the overall water splitting.     

Mo/P doped NiFeSe as bifunctional electrocatalysts for overall water splitting

Designing high-efficiency catalysts for overall water splitting is critical to reduce the cost of hydrogen fuel as a clean and renewable energy source in future society. In this work, a Mo-, P-codoped NiFeSe was successfully synthesized on nickel foam (NF) by one-step electrodeposition. Through the doping strategy, the conductivity can be well promoted, and the production of nanosheets on the catalyst surface and active phases during hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) provided much more active sites, which leaded to efficient HER/OER performances of as-synthesized Mo-, P-codoped NiFeSe catalysts, i.e., a low overpotential of 100 mV/200 mV at current density of 10 mA cm⁻² in 1.0 M KOH with stability of 95 h/60 h, respectively. It only required 1.53 V to deliver a current density of 10 mA cm⁻² in overall water splitting and maintained outstanding durability for 100 h. This work is beneficial to future design of high efficient and low-cost bifunctional catalysts for overall water splitting.     

Sulfuration of hierarchical Mn-doped NiCo LDH heterostructures as efficient electrocatalyst for overall water splitting

Constructing efficient bifunctional electrocatalysts for both cathode and anode is of great importance for obtaining green hydrogen by water splitting. Herein, sulfuration of hierarchical Mn-doped NiCo LDH heterostructures (Mn–NiCoS₂/NF) is constructed as a bifunctional electrocatalyst for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) via a facile hydrothermal-annealing strategy. Mn–NiCoS₂/NF shows an overpotential of 310 mV at 50 mA cm⁻² for OER and 100 mV at 10 mA cm⁻² for HER in 1.0 M KOH. Moreover, only 1.496 V@10 mA cm⁻² is required for overall water splitting by using Mn–NiCoS₂/NF as catalyst dual electrodes in a two-electrode system. The excellent performance of Mn–NiCoS₂/NF should be attributed to the ameliorative energy barriers of adsorption/desorption for HO⁻/H₂O through the modification of electronic structure of NiCo basal plane by Mn-doping and the acceleration of water dissociation steps via rich delocalized electron inside sulfur vacancies. The construction of hierarchical Mn–NiCoS₂/NF heterostructures provides new prospects and visions into developing efficient-advanced electrocatalysts for overall water splitting.     

Construction of heterostructure interface with FeNi2S4 and CoFe nanowires as an efficient bifunctional electrocatalyst for overall water splitting and urea electrolysis

The design of high-performance non-noble-metal-based electrocatalysts for electrooxidation reactions involving splitting of water molecule for energy and environmental applications is the need of the hour. In this study, we report the electrocatalytic performance of a nanocomposite catalyst of FeNi₂S₄ nanoparticles/CoFe nanowires supported on nickel foam that was prepared by a simple hydrothermal method. The electrocatalyst has several advantages, such as the nanocomposite structure, relatively high electrical conductivity, and synergistic effect between FeNi₂S₄ and CoFe. These characteristics enhanced the catalytic efficiency of FeNi₂S₄/CoFe electrode, gaining small overpotentials of 380 and 207 mV for oxygen and hydrogen evolution reactions, respectively, at a current density of 100 mA cm^?2. The charge transfer processes are significantly improved by the electron pairs from FeNi₂S₄ and CoFe, as well as by the enhanced active sites at the electrode-electrolyte interface and their bonding interactions. The electrooxidation of urea was also explored, which showed a lower overpotential of 230 mV to reach 100 mA cm^?2 current density. Interestingly, FeNi₂S₄/CoFe was successfully employed as cathode and anode for urea-assisted water electrolysis, utilizing 1.56 V to produce 10 mA cm^?2 current density, which is approximately 160 mV below that for water electrolysis, thus verifying the lower energy consumption during electrolysis. These results indicate that nanoparticle and nanowire composite catalysts can be used for wastewater treatment and green energy production applications.     

Bimetallic metal-organic framework derived electrocatalyst for efficient overall water splitting

The development of bifunctional catalysts that can be applied to both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is widely regarded as a key factor in the production of sustainable hydrogen fuel by electrochemical water splitting. In this work, we present a high-performance electrocatalyst based on nickel-cobalt metal-organic frameworks for overall water splitting. The as-obtained catalyst shows low overpotential to reaches the current density of 10 mA cm⁻² with 249 mV for OER and 143 mV for HER in alkaline media, respectively. More importantly, when the electrolyzer was assembled with the as-prepared catalyst as anode and cathode simultaneously, it demonstrates excellent activity just applies a potential of 1.68 V to achieve 10 mA cm⁻² current density for overall water splitting.     

Ni/NiO@rGO as an efficient bifunctional electrocatalyst for enhanced overall water splitting reactions

Herein, we fabricated bifunctional, noble metal-free, highly efficient nickel/nickel oxide on reduced graphene oxide (Ni/NiO@rGO) by chemical synthesis approach for electrochemical water splitting reaction. Its structural and morphological characterization using thermogravimetric analysis (TGA), transmission electron microscopy (TEM), field emission scanning electron microscope (FESEM), energy dispersive analysis of X-ray (EDAX) and X-ray diffraction (XRD) represents, Ni/NiO@rGO is having Ni/NiO NPs ∼10 nm (±2 nm) on graphene oxide with face-centered cubic (FCC) crystal structure. Moreover, the presence of Ni/NiO (2.26%), O (6.56%), N (0.74%) and C (90.44%) from EDAX analysis further confirms the formation of Ni/NiO@rGO and it also supported by FTIR studies. This nanocatalyst is examined further for electrocatalytic water splitting reactions (HER and OER). It demonstrated low overpotential 582 mV to achieve current density at 10 mA cm⁻² and smaller Tafel slope of 63 mV dec⁻¹ obtained in 0.5 M H₂SO₄ towards HER. Also, at the other end at onset potential of 1.6 V vs. RHE towards OER. It demonstrated low overpotential 480 mV to achieve current density at 10 mA cm⁻² and smaller Tafel slope of 41 mV dec⁻¹ in 0.5 M KOH towards OER observed. Hydrogen fuel is eco-friendly to the environment and noteworthy performance of earth-saving reactions.     

Construction of ZIF-67/MIL-88(Fe,Ni) catalysts as a novel platform for efficient overall water splitting

Constructing bifunctional non-precious metal electrocatalysts is necessary for effective overall water splitting (OWS), but challenging. Herein, a novel hybrid nanostructure of ZIF-67/MIL-88(Fe, Ni), denoted as Co-M-Fe/Ni(x) (x represents the mass of ZIF-67), was successfully synthesized by hydrothermal and in-situ growth method, and showed a highly efficient and stable bifunctionality of both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline electrolyte. The Co-M-Fe/Ni(150) exhibited excellent OER performance with a low overpotential of 269 mV and 149 mV @ 10 mA cm^?2 for OER and HER in 1 mol L^?1 KOH, respectively. With Co-M-Fe/Ni(150) as cathode and anode, the integrated OWS device had achieved low potential of 1.52 V @ 10 mA cm^?2, exhibiting its excellent performance of OWS. Based on the results of experiments, ZIF-67 and MIL-88(Fe, Ni), as metal-organic frameworks (MOFs), which have a large specific surface area, uniform distribution of porous structures facilitates charge transmission, promoting the penetration of electrolytes, and improves electron transfer rate. The mechanism of the superior electrocatalytic performance of Co-M-Fe/Ni(150) may be attributed to the synergy of ZIF-67 and MIL-88(Fe, Ni). This work provides guidance for the rational design or optimization of non-noble composites for energy conversion.     

Lanthanum doped copper oxide nanoparticles enabled proficient bi-functional electrocatalyst for overall water splitting

The need for a clean and an environmentally non-degrading sustainable energy resource has grown worldwide due to the huge depletion of other fuel sources, as a result, production of hydrogen by electrochemical water splitting is considered as a potential answer to this pertaining need. However, development of low-cost electrocatalyst as a replacement for Pt and RuO₂ for both Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) remains a significant challenge for the production of hydrogen at a larger scale. This study presents the synthesis of non-noble metal-based lanthanum doped copper oxide nanoparticles as a potential bi-functional electrocatalyst for overall water splitting in alkaline electrolyte. The optimized 1% lanthanum (La) doped CuO electrocatalyst exhibits outstanding OER and HER activity in 1.0 M KOH electrolyte posting a potential of 1.552 V vs RHE for OER and −0.173 V vs RHE for HER at a current density of ~10 mAcm⁻². Significantly, the functional bi-catalyst exhibits a low cell voltage of 1.6 V to achieve overall water splitting at a current density of 10 mAcm⁻² along with long-term stability of 13.5 h for a cell voltage of 2.25 V at a constant current density of 30 mAcm⁻² with only 20% initial current lose after 13.5 h. The results demonstrate that the incorporation of the rare-earth element onto CuO nanoparticles has made it a viable high-end non-noble electrocatalyst for overall water splitting.     

In-situ growth of Ni–CoSe2 on biomass-derived carbon tubes as an efficient electrocatalyst for overall water splitting

A Ni–CoSe₂/BCT composite composed of biomass-derived carbon tubes and transition metal selenides was successfully constructed and explored as a highly efficient bifunctional electrocatalyst for overall water splitting.

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NiSe2@NixSy nanorod on nickel foam as efficient bifunctional electrocatalyst for overall water splitting

Electrocatalytic water splitting technology has become one of the most promising methods to solve the energy crisis, which can produce a large amount of high purity H₂ and O₂. It is necessary to develop efficient and stable water splitting catalyst for reducing the overpotential of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) and accelerating their reaction kinetics. A series of NiSe₂@Ni_xS_y nanoarrays was firstly in situ grown on the nickel foam through the typical hydrothermal, selenylation and sulfuration pathways. The Na₂SeO₃ homogeneous solution is formed by hydrothermal and the selenization process is done at the temperature of 180^。C. Then the nickel foam (NF) is put into the Na₂SeO₃ solution to form NiSe₂ material at the temperature of 120^。C. After that, the NiSe₂ materials were sulfuretted with different amounts of sulfur to form NiSe₂@Ni_xS_y hybrid materials. The experimental results demonstrate that the NiSe₂@Ni_xS_y material as a 3D electrode can maximize the synergistic reaction between NiSe₂ and Ni_xS_y, thus exhibiting an efficient and comprehensive water splitting performance. The NiSe₂@Ni_xS_y-1 material presents a superior OER performance with requiring the overpotential of only 206 mV at 100 mA cm⁻². Moreover, the NiSe₂@Ni_xS_y-0.3 material presents a superior HER performance with requiring the overpotential of only 148 mV at 100 mA cm⁻². It is worth noting that when NiSe₂@Ni_xS_y-1 material and the NiSe₂@Ni_xS_y-0.3 material was used as cathode and anode, only 1.53 V cell voltage is needed to produce a current density of 10 mA cm⁻² throughout the water splitting process, which is one of the smallest values reported so far. Density functional theory calculations results show that the Ni₃S₂ has the best water adsorption energy, so it is an active species in the process of catalysis. However, NiSe₂ has more density distribution around the Fermi level, indicating that it exhibits better metallic properties, which makes the NiSe₂@Ni_xS_y-1 hybrid material exhibit better electronic conductivity.     

Hierarchical flower-like CoS2-MoS2 heterostructure spheres as efficient bifunctional electrocatalyst for overall water splitting

Electrochemical water splitting technique requires high-efficient bifunctional electrocatalysts to obtain large-scale hydrogen production for resolving the impending energy and environmental crisis. Herein, hierarchical flower-like CoS₂-MoS₂ heterostructure hybrid spheres grown on carbon cloth (CoS₂-MoS₂/CC) were prepared by sulfuring wheel-shaped polyoxometalate {Co₂₀Mo₁₆}. The as-prepared CoS₂-MoS₂/CC as bifunctional electrocatalyst manifests excellent alkaline oxygen evolution and hydrogen evolution activities with low overpotentials of 240 mV for OER and 60 mV for HER at 10 mA cm^?2, respectively. When assembled as two-electrode cell, CoS₂-MoS₂/CC delivers an extremely low cell-voltage of 1.52 V at 10 mA cm^?2 accompanied with remarkable long-term durability. Additionally, CoS₂-MoS₂/CC exhibits favorable overall-water-splitting performance in simulated seawater. The superior performance of CoS₂-MoS₂/CC should be ascribed to the optimized intrinsic electron structure via electron transfer from MoS₂ to CoS₂ along with the synergistic effect of well-exposed heterostructure interfaces and favorable diffusion channels. This work offers a practical strategy for exploring high-efficient bifunctional electrocatalysts for overall water splitting.     

Nitrogen doped FeCoNiS nanoparticles on N,S-co-doped vertical graphene as bifunctional electrocatalyst for water splitting

It's important to develop an economical and efficient electrocatalyst for water splitting. Nitrogen-doped FeCoNiS nanoparticles are supported on N, S-co-doped vertical graphene (N–FeCoNiS/SVG) by one-step electrodeposition. The SEM and TEM results show that 30–115 nm nanoparticles grow uniformly on SVG. The XRD results show that N–FeCoNiS/SVG is a polycrystalline material. N–FeCoNiS/SVG exhibits excellent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) potentials of 44 mV and 138 mV (10 mA cm^?2), respectively, in 1 M KOH. The Faraday efficiency of N–FeCoNiS/SVG for overall water splitting is about 97%. The electrocatalyst also shows excellent stability over 24 h. The XPS results illustrate that N-doping promotes the electron transfer between metal and heteroatom and effectively modulates the electronic structure of FeCoNiS. N–FeCoNiS/SVG has excellent electrocatalytic performance for water splitting. This work provides theoretical and technical support for the study of water splitting bifunctional electrocatalysts.     

Uniform cobalt nanoparticles embedded in nitrogen-doped graphene with abundant defects as high-performance bifunctional electrocatalyst in overall water splitting

Co nanoparticles with uniform size (about 5 nm) embedded in N-doped graphene (Co-NG) were explored in this work. The introduction of a second carbon source of citric acid during synthesis prevented the Co atoms from growing up, thus regulating the size of the cobalt nanoparticles. N atoms in N-doped graphene had more lone-pair electrons, making it easier to capture electrons from hydrated ions, and facilitating the dynamics procedure of HER. Furthermore, N dopant rendered larger positive charge density on the adjacent carbon atoms, which was conducive to OER and HER. At 10 mA cm^?2 of the current density, the Co-NG/CC catalyst's overvoltage of HER was 78 mV, approaching that of 20% Pt/C (59 mV), an efficient precious metal electrocatalyst for HER, while its overvoltage of OER was about 225 mV, 12.5% lower than that of RuO₂ (257 mV, a common precious metal oxide OER electrocatalyst). In addition, this Co-NG/CC composite bifunctional catalyst displayed good electrochemical stability in alkali solution and might be designed as a dual-function catalyst in the application of overall water splitting. The cell voltage of Co-NG/CC//Co-NG/CC was only 1.66 V, approaching to that of full precious metal cell of Pt/C//RuO₂ (1.52 V), and revealing the good commercial application prospects of this composite bifunctional catalyst.     

ZIF-67-derived Co,Ni and S co-doped N-enriched porous carbon polyhedron as an efficient electrocatalyst for oxygen evolution reaction (OER)

Rational fabrication of highly efficient and non-precious metal electrocatalysts for oxygen evolution reaction (OER) are of great importance for renewable energy exploitation to solving the energy crisis and environmental problems. In this paper, we report a novel hybrid nanostructure with Co, Ni and S co-doped N-enriched porous carbon polyhedron (CoNi_xS_y/NCP) via a absorption-pyrolysis-sulfuration strategy derived from zeolitic imidazolate framework-67 (ZIF-67) and explored its electrocatalytic performance for OER. During the synthesis process, Ni²⁺ is abosrbed within the pores or surface of ZIF-67 and Ni/ZIF-67 can be transformed into the Co and Ni co-doped porous carbon frameworks when it is sulfurazed at 800 °C. NiS₂ and NiCo₂S₄ nanoparticles formed at high temperature are homogeneously dispersed in porous carbon and can activate its electrocatalytic performance. The porous carbon can enhance the electrochemical surface area and charge transfer efficiency. Benefiting from the synergistic effects between highly active NiS₂, NiCo₂S₄, and porous carbon, CoNi_xS_y/NCP electrocatalyst exhibits excellent electrocatalytic performance. The results show that CoNi_xS_y/NCP also exhibits a potential as low as 1.51 V to achieve 10 mA/cm² current density and extremely stability towards OER. The good electrocatalytic activity of CoNi_xS_y/NCP further suggest its great potential as an efficient eletctocatalyst for sustainable energy applications.