Nickel Sulfide Research Articles

Unlocking enhanced electrochemical performance through oxygen–nitrogen dual functionalization of iron–nickel–sulfide for efficient energy storage systems

This study showcases a supercapacitor device with oxygen–nitrogen dual functionalized and sulfurized iron–nickel hydroxysulfide, demonstrating high performance and stability for energy storage.

Expression of concern: Engineering the optical properties of nickel sulphide thin films by zinc integration for photovoltaic applications.

Expression of concern for 'Engineering the optical properties of nickel sulphide thin films by zinc integration for photovoltaic applications' by Junaid Younus et al., RSC Adv., 2023, 13, 27415-27422, https://doi.org/10.1039/D3RA04011A.

Three-dimensional biotemplate-loaded nickel sulfide vacancies engineered to promote the absorption of electromagnetic waves.

Vacancy engineering offers an appealing strategy for modifying the electronic structure of transition metals. Transition metals with abundant sulfur vacancies can significantly contribute to the microwave absorption capabilities of absorbers. In this study, an NixSy@De composite material was synthesized through a straightforward hydrothermal synthesis technique. The effective absorption bandwidth (EAB) of this composite material reached 9.86 GHz at 1.44 mm. A minimum reflection loss (RLmin) of -33.61 dB at 1 mm was achieved, and after mild etching, the RLmin further improved to -93.53 dB at 1.16 mm to achieve a high-attenuation microwave absorption. The exceptional performance of NixSy@De for the absorption of electromagnetic waves (EMWs) is based on its high dielectric loss, substantial magnetic loss, and excellent impedance matching. This work combines transition metal sulfides with three-dimensional biotemplated diatomite, providing valuable insights into the design of advanced EMW absorbing materials.

Strategic cation exchange induced 2D nickel sulphide nanoplates with enhanced oxygen evolution reaction performance

A cation exchange method enables the synthesis of highly crystalline 2D NixS nanoplates with fine-tuned morphology. These nanoplates exhibit excellent OER performance, achieving a 329 mV overpotential at 10 mA cm−2 and a 52 mV dec−1 Tafel slope.

Hydrothermally Synthesized NiS2 and NiSO4(H2O)6 Nanocomposites and its Characterizations

The present manuscript discusses an in-depth explanation of the synthesis and characterization of nickel sulphide (NiS2) and nickel sulphate [NiSO4(H2O)6] nanocomposites. The phase analysis was performed through x-ray diffraction (XRD), revealing the presence of NiS2 and NiSO4(H2O)6 nanocomposites, along with the presence of deuterium. The synthesized material exhibited absorbance in the visible region, with an optimized band gap of 1.0 eV. The presence of carbon spheres was confirmed through morphological analysis performed through field emission scanning electron microscopy (FESEM), depicting the growth of NiS2 on the surface of carbon spheres and the presence of nanosheets of NiSO4(H2O)6. These techniques provide a detailed explanation of the crystallite size for the nanocomposites, their structural properties and optical properties. The material showed a narrow band gap making it highly suitable for solar cell applications.

Kinetic of Dissolution of Nickel Limonite Calcine by Sulfuric Acid Solution

Currently, more than 60% of nickel processing is carried out using nickel sulfide as a raw material. Nonetheless, due to the depletion reserves of nickel sulphide, nickel laterite has drawn a lot of interest to be processed as raw material. Nickel laterite in Indonesia is generally found in low grades, with nickel concentration of <1.15%. One method of treating nickel limonite is leaching in a sulfuric acid solution. This study aims to determine the reaction rate in the leaching process of calcine nickel limonite and the effect of sulfuric acid concentration and leaching temperature on the percent nickel extraction. In this research, the limonite ore from Pomalaa, Southeast Sulawesi, Indonesia, which has undergone a reduction process, was used as raw material. This research was conducted by leaching method on nickel limonite calcine using sulfuric acid reagent with 0.2, 0.5, and 1 M concentration variation, temperature variations of 60, 70, and 90°C, stirring speed 500 rpm, and %S/L (w/w) 10%. In this leaching research, the activation energy obtained at a sulfuric acid concentration of 0.2, 0.5, and 1 M are 13,7379 kJ/mol, 19,7582 kJ/mol, 20,3161 kJ/mol, respectively. The leaching process of nickel limonite calcine was controlled by diffusion. The optimum nickel extraction percentage in this study was 97.45%, obtained at a concentration of 1 M sulfuric acid, temperature of 70 °C, and leaching time of 240 minutes.

Nanofiber-based electrode current collector for high-energy Li-S batteries towards practical application for energy storage

The slow sulfur electrochemical reactions are one of the key factors hindering the practical use of lithium-sulfur (Li-S) batteries. However, the polysulfide shuttling and the sluggish redox kinetics, which emerge simultaneously in sulfur cathode, hinder the commercial application of Li-S batteries. Herein, we employ a design to solve the above-mentioned problems via building nitrogen-doping carbon nanofibers with twinborn nickel sulfide nanoparticles (NiS2/Ni3S4@NCNF) as self-supporting current collector for Li-S batteries. Experimental results and theoretical calculations show that the three-dimensional cross-linked carbon structure promotes Li-ion/electron transfer and physically offers wide internal space for sulfur accommodation. Meanwhile, powerful capability of chemical anchoring of the polysulfides endowed by NiS2 mitigates the shuttle effect. Notably, the surface of mixed-valence Ni3S4 has more active sites, which can effectively reduce the energy barrier due to its high catalytic activity and fast sulfur conversion from solid Li2S/Li2S2 to soluble polysulfides. Based on these merits, the Li-S battery with NiS2/Ni3S4@NCNF shows stable sulfur electrochemistry including a highly reversible capacity of 1212.8 mAh g−1 at 0.2C with capacity retention rate of 75.3 % after 100 cycle, and an excellent cycle stability of pouch battery. This work provides a promising strategy to build advanced sulfur current collectors for practical Li-S battery.

Formation of the Heterojunction Based on Titania Modified with Ni and Ag Sulfide Via SILAR Method - Electrochemical and Photoelectrochemical Activity

The great interest of TiO2 nanotubes (TiNT) is justified by large surface area, high degree of ordering, facilitated charge transport along the nanotube, mechanical strength, strong UV absorption and light scattering due to the pore specific arrangement well as wide range of potential applications in solar cells, photocatalysis and sensors [1]. However, due to the wide energy band gap of TiO2 (3.2 eV) its photoactivity is limited and therefore titania based heterojunction are formed with the photoabsorber being active in the visible range [2]. In line with this strategy, we present electrochemical and photoelectrochemical activity of TiNT modified by NiS and AgS.The electrode is fabricated via electrochemical anodization of Ti foil, thermal annealing providing anatase phase and finally Successive Ionic Layer Adsorption and Reaction (SILAR) was carried out using silver, nickel and sulfur ions precursor and with different number of deposition cycles. The characteristic Ag-S, Ag-O and S-O peaks appearing on Raman spectra indicating successful SILAR modification. The cyclic voltammetry curves for TiNT, NiS/TiNT, AgS/TiNT and AgS/NiS/TiNT electrode were registered in 0.5 M Na2SO4 (Fig.1a). Peaks found on the anodic branch of the AgS/NiS/TiNT electrode at 0 V and +0.3 V vs. Ag/AgCl/0.1 M KCl are assigned to oxidation of Ag0 to Ag1+ and Ag1+ to Ag2+, respectively. When the scan went towards cathodic direction, peak located at +0.1 V and -0.1 V indicates reduction of Ag2+ to Ag1+ and Ag1+ to Ag0, respectively [3]. Furthermore, the linear voltammetry measurements performed under visible light illumination in 0.5 M Na2SO4 is presented in Fig.1b. The best photoactivity was reached for the AgS/NiS/TiNT electrode when only 5 deposition cycles for each metal precursor was applied. The photocurrent registered at +0.5 V reaches ca. 40 µA/cm2 which is 20 times higher than for pure TiNT.Summing up, modification of titania nanotubes by nickel and silver sulfides significantly enhanced material photoelectrochemical response under visible light. Moreover, it has been proved that this synergetic effect originated from the titania/metal sulphide heterojunction that can be achieved using SILAR method.Research is financed by National Science Centre (Poland): Grant no. 2020/39/I/ST5/01781[1] K. Siuzdak et al. RSC Advances, 5 (2015) 50379, DOI:10.1039/c5ra08407e[2] S. Chandrasekaran et al. Chemical Society Reviews, 48 (2019) 4178, DOI:10.1039/c8cs00664d[3] J.R.N. Santos et al. Electrocatalysis, 13 (2022) 713, DOI: 10.1007/s12678-022-00754-2 Figure 1

Ce Hydroxide-Interfaced NiFe Sulfide Electrocatalyst with Improved Performance for the Oxygen Evolution Reaction.

The development of electrochemically inexpensive, durable, and active electrocatalysts for the oxygen evolution reaction (OER) is attracting considerable attention. The heterogeneous interfacing might regulate the electronic structure and further improve the electrochemical activity. Herein, a Ce(OH)3 nanoparticle-interfaced Fe-doped nickel sulfide (Ce(OH)3@Fe-Ni3S2) electrocatalyst was prepared to improve the OER performance. The fabricated electrocatalyst displayed excellent intrinsic activity and long-term stability in 1 M KOH for the OER. The catalyst shows an ultralow overpotential of 195 mV at a current density of 10 mA cm-2 and a Tafel slope of 52 mV dec-1, which are remarkably smaller than those of the control samples. This excellent electrocatalytic activity is attributed to the incorporation of Ce(OH)3 nanoparticles on the surface of the Fe-Ni3S2 nanosheet, which increases the electrochemical activity and enlarges the active surface area of the catalyst. In comparison to previous nonprecious OER electrocatalysts, the prepared Ce(OH)3@Fe-Ni3S2 exhibits greater electrocatalytic activity and longer durability, allowing for the selection of new electrocatalysts for practical applications.

Sericin-derived carbon wrapped NiS2/V2O3 heterostructure for high-rate capability sodium-ion batteries

Sodium-ion batteries (SIBs) present a prospective solution for energy storage, benefitting from their cost-effectiveness and the abundant availability of sodium reserves on Earth. The effective design of electrode materials with superior cyclability and exceptional rate capability are essential for their widespread application. In this paper, a heterostructure between binary nickel sulfide (NiS2) and vanadium trioxide (V2O3) was initially synthesized by a feasible hydrothermal and subsequent high-temperature calcination technique, which consisted of coin-like V2O3 tiny sheets adhering to the surface of NiS2 microsphere. After coating a layer of sericin-derived carbon (SC) films onto surface of NiS2/V2O3, as-synthesized NiS2/V2O3@SC composite anodes for SIBs exhibited impressive electrochemical Na+ storage performances involving an initial discharge capacity of 671.2 mAh g−1 at 1 A g−1, a capacity decay of only 0.043 and 0.066 % per cycle within 1000 cycles at 1 A g−1 and 8 A g−1, and the rate capability of 32 A g−1 with a capacity output of 406.4 mAh g−1. The NiS2/V2O3 heterostructure with a hierarchical structure will beneficially alleviate agglomeration and volumetric expansion of active materials, improve electrical conductivity, and more importantly, enhance electrochemical kinetic transport of Na+, which makes it a potential anode application for SIBs.

Mesoporous Nickel Sulfide Microsphere Encapsulated in Nitrogen, Sulfur Dual-Doped Carbon with Large Subsurface Region for Enhanced Sodium Storage.

Nickel sulfides are promising anode candidates in sodium ion batteries (SIBs) due to high capacity and abundant reserves. However, their applications are restricted by poor cycling stability and slow reaction kinetics. Thus, mesoporous nickel sulfide microsphere encapsulated in nitrogen, sulfur dual-doped carbon (MNS@NSC) is prepared. The packaged structure and carbon matrix restrain the volume variation together, the N, S dual-doping improves the electronic conductivity and offers extra active sites for sodium storage. Ex-situ X-ray diffraction appeals copper collector adsorbs polysulfide to inhibit the polysulfide accumulation and enhance conductivity. Moreover, the large subsurface attributed to C-S-S-C bonding further boosts pseudocapacitive capacity, conducive to charge transfer. As a result, MNS@NSC delivers a high reversible capacity of 640.2 mAh g-1 after 100 cycles at 0.1 A g-1, an excellent rate capability (569.8 mAh g-1 at 5 A g-1), and a remained capacity of 513.8 mAh g-1 after undergoing 10000 circulations at 10 A g-1. The MNS@NSC|| Na3V2(PO4)3 full cell shows a cycling performance of specific capacity of 230.8 mAh g-1 after 100 cycles at 1 A g-1. This work puts forward a valid strategy of combing structural design and heteroatom doping to synthesize high-performance nickel sulfide materials in SIBs.

Pyrite copper nickel sulfide for stable hydrogen evolution reaction in alkaline media

The alkaline hydrogen evolution reaction is a promising solution to meet future energy demand due to the sustainable production of hydrogen via water electrolysis. The development of copper nickel sulfide (CuNiS) electrocatalysts for hydrogen evolution reaction (HER) relies on robust active sites without degradation. However, the performance of CuNiS depends on the nature of sulfur precursors and complexing agents since the copper and sulfur oxidation states determine the adsorption and release of H2. The CuNiS synthesized with thioacetamide and 3-mercaptopropionic acid as sulfur source and complexing agent, respectively, at 100°C for 10h delivered a lower overpotential of −96 mV to achieve a current density of −10 mA cm−2 in 1 M KOH electrolyte. The positive and negative shifts in binding energy peaks of Ni and S, respectively, caused charge redistribution and charge transfer between metals and S. The transfer of electrons from Ni to Cu atoms decreases the hydrogen binding energy and accelerates the Had desorption process, which leads to the subsequent formation of H2. Moreover, the negative shift in S improves the electron occupation, which helps with proton adsorption and the release of H2.

Catalytic and antibacterial activity of annealed nickel sulfides quantum dots

In this research, nickel sulfide (NiS) quantum dots (QDs) were prepared through the co-precipitation method and annealed at same temperature with different time. This study aimed to check the influence of annealing time on catalytic reduction of rhodamine B () and antibacterial efficacy against E. coli. The synthesized NiS were characterized thorough XRD, UV-Vis, SAED and TEM analysis to check the effect of annealing time on structural, optical and morphological of QDs. XRD spectra depicted that crystallinity of the NiS increased upon enhancing the annealing time. Electronic transition spectroscopy exhibited the blue shift by increasing annealing time, leading to band gap energy enhancement. TEM images demonstrated that agglomeration of the QDs increased by increasing the annealing time. EDS spectra verified the formation of NiS QDs. SAED analysis confirmed the polycrystalline behavior of host and annealed NiS. The pure NiS demonstrated substantial catalytic reduction of dye in acidic medium comparison to other media. Moreover, host sample (NiS) exhibited maximum inhibition zone for E. coli at higher concentration.

NixSy/NF composites assembled by sulfidation of nickel foam (NF) for highly effective capture of iodine

Under a facile one-step hydrothermal reaction by changing thiourea dosage to regulate sulfidation degree of nickel foam (NF), a variety of nickel sulfide composites of n-NixSy/NF (1-Ni3S2/NF, 3-Ni3S2 and 6-Ni3S2/Ni9S8) were prepared and utilized to capture iodine for the first time. The compositions and structures of the composites and their influence on iodine adsorption performance were elaborated in detail. During adsorption, Ni0 in NF and Ni0/S2− in Ni3S2/Ni9S8 both served as reducing agents to achieve the chemisorption for iodine, where the Ni0 and S2− were oxidized to Ni2+ and elemental S0 (S8), and the I2 molecules were reduced to I− which then reacted with the Ni2+ to form NiI2. The 1-Ni3S2/NF, 3-Ni3S2 and 6-Ni3S2/Ni9S8 exhibited different iodine adsorption capacities (qmI) of 1442, 1109 and 420 mg/g for iodine vapor, and 1191, 869 and 296 mg/g for iodine in solutions, respectively, giving the largest qmI of 1442 (for I2 vapor) and 1191 mg/g (for I2 in solution) by 1-Ni3S2/NF. The capture mechanism for iodine in solution was mainly by chemisorption, while for iodine vapor, profiting from the three-dimensional skeleton of NF, besides the chemisorption, physical sorption also played a role. After γ irradiation, the structures of n-NixSy/NF were well-maintained and iodine adsorption performance did not deteriorate, indicating the good radiation resistance. This work provides an important reference for tailoring new kinds of cost-effective sorbents to trap iodine from radioactive nuclear wastes.

Iron and vanadium co-doped Ni3S2 flower like nanosheets as an efficient electrocatalysts for water splitting

For the production of sustainable hydrogen energy from water electrolysis, it is now essential to create an efficient bifunctional electrocatalysts for OER and HER (oxygen and hydrogen evolution reaction). We have synthesized a bi-metallic heterogeneous electrocatalyst of iron and vanadium codoped nickel sulphide (FeV-Ni3S2) flower like nanosheets self-supported on conductive nickel foam (NF) substrate by a typical hydrothermal method. Herein, our investigation is focused on achieving an efficient electrocatalytic performance and long-term stability (> 48 h) in an alkaline environment (1 M KOH). The results of FeV-Ni3S2/NF exhibits an outstanding electrochemical performance with lower overpotentials of 149 mV for HER and 183 mV for OER at 10 mA cm−2, and a lower cell voltage of 1.56 V, respectively. The lattice distortion in Ni3S2 caused by FeV-doping, and the enrichment of sulphur active edge sites contributes to the improved electrochemical performance of FeV-Ni3S2/NF. Moreover, the interconnected flower like nanosheets increasese the conductivity, density of active sites and electrochemical surface area to facilitate the mass transport of reactants, benefiting stable water electrolysis for efficient hydrogen production. This work will provide novel insights into the design of bi-metal-doped materials for energy conversion and storage applications.

Engineering Phase to Reinforce Dielectric Polarization in Nickel Sulfide Heterostructure for Electromagnetic Wave Absorption.

Engineering phase transition in micro-nanomaterials to optimize the dielectric properties and further enhance the electromagnetic microwave absorption (EMA) performance is highly desirable. However, the severe synthesis conditions restrict the design of EMA materials featuring controllable phases, which hinders the tunability of effective absorption bandwidth (EAB) and leads to an unclear loss mechanism. Herein, a seed phase decomposition-controlled strategy is proposed to induct nickel sulfide (NiSx) absorbers with controllable phases and hollow sphere nature. Transmission electron microscopy holography and theoretical calculations evidence that the reconstruction of atoms in phase transition induces numerous heterogeneous interfaces and lattice defects/sulfur vacancies to cause varied work functions and local electronic redistribution, which contributes to reinforced dielectric polarization. As a result, the optimized NiS2/NiS heterostructure enables enhanced EM attenuation capability with a wide EAB of 5.04GHz at only 1.6mm, compared to that of NiS2 and NiS. Moreover, the correlation between EAB and NiS phase content is demonstrated as the "volcano" feature. This study on the concept of phase transition of micro-nanomaterials can offer a novel approach to constructing highly efficient absorbers for EMA and other functionalities.

Experimental and computational study of annealed nickel sulfide quantum dots for catalytic and antibacterial activity

This research investigates the hydrothermal synthesis and annealing duration effects on nickel sulfide (NiS2) quantum dots (QDs) for catalytic decolorization of methylene blue (MB) dye and antimicrobial efficacy. QD size increased with longer annealing, reducing catalytic activity. UV–vis, XRD, TEM, and FTIR analyses probed optical, structural, morphological, and vibrational features. XRD confirmed NiS2's anorthic structure, with crystallite size growing from 6.53 to 7.81 ​nm during extended annealing. UV–Vis exhibited a bathochromic shift, reflecting reduced band gap energy (Eg) in NiS2. TEM revealed NiS2 QD formation, with agglomerated QD average size increasing from 7.13 to 9.65 ​nm with prolonged annealing. Pure NiS2 showed significant MB decolorization (89.85%) in acidic conditions. Annealed NiS2 QDs demonstrated notable antibacterial activity, yielding a 6.15 ​mm inhibition zone against Escherichia coli (E. coli) compared to Ciprofloxacin. First-principles computations supported a robust interaction between MB and NiS2, evidenced by obtained adsorption energies. This study highlights the nuanced relationship between annealing duration, structural changes, and functional properties in NiS2 QDs, emphasizing their potential applications in catalysis and antibacterial interventions.

A novel fluorescent sensor with an overtone peak reference for highly sensitive detection of mercury (II) ions and hydrogen sulfide: Mechanisms and applications in environmental monitoring and bioanalysis

The present study introduces a novel fluorescent sensor with an overtone peak reference designed for the detection of mercury (Ⅱ) ions (Hg2+) and hydrogen sulfide (H2S). The study proposes two novel response mechanisms that hinges on the synergistic effect of cation exchange dissociation (CED) and photo-induced electron transfer (PET). This sensor exhibits a remarkable detection limit of 2.9 nM for Hg2+. Additionally, the sensor reacts with H2S to generate nickel sulfide (NiS) semiconductor nanoparticles, which amplify the fluorescence signal and enable a detection limit of 3.1 nM for H2S. The detection limit for H2S is further improved to 29.1 pM through the surface functionalization of the nanomaterial with pyridine groups (increasing reactivity) and chelation of gold nanoparticles (AuNPs), which enhances the sensor's specificity. This improvement is primarily due to the surface plasmon resonance (SPR) of AuNPs and their affinity for H2S. The single-emission strategy can yield skewed results due to environmental changes, whereas the overtone peak reference strategy enhances result accuracy and reliability by detecting environmental interference through reference emission peaks. In another observation, the low-toxicity dihydropyrene-bipyridine nanorods (TPP-BPY) has been successfully utilized for both endogenous and exogenous H2S detection in vivo using a mouse model. The successful development of TPP-BPY is expected to provide an effective tool for studying the role of H2S in biomedical systems.

Enhancing nickel grade and recovery with counter-current washing of the concentrated bubbly-zone of a single stage REFLUX™ Flotation Cell

The recovery and concentration of the nickel sulphide mineral, pentlandite, present several challenges due to its relatively slow flotation, leading to excessive hydrophilic gangue minerals in the concentrate. The REFLUX™ Flotation Cell (RFC™) offers the potential for a significant hydrodynamic advantage over conventional flotation. Much of this advantage is due to the replacement of the pulp and froth phases with a concentrated bubbly zone, which in turn supports more intense counter-current washing by permitting a powerful and effective positive bias flux. Thus, the aim of this study was to investigate the nickel recovery and silica rejection in the RFC™, by applying a wide range of positive bias fluxes. The focus was on a single stage of separation in the RFC™ using a feed flux of 0.63 cm/s at a feed nickel grade of 2.1%. At the lowest bias flux of 0.1 cm/s, a nickel grade of 7.5% was obtained at a single stage recovery of 70.2%. By increasing the bias flux to 0.42 cm/s, the grade increased to 9.7% but the recovery fell to 64.9%. With an extreme bias flux of 1.04 cm/s, the grade reached 12.3%, while the recovery fell to 54.7%. The selectivity, given by the nickel recovery relative to the silica recovery, was estimated to be 121 at the highest bias flux, declining sharply with a reduction in the bias flux. The performance ratio proposed by Parkes et al (2022) was quantified by comparing the RFC™ performance with the batch kinetic results from a mechanical cell, the product grade being ∼7%. The performance ratio was based on the experiment at the lowest bias flux used in the RFC™, and found to be at least 6, meaning the RFC™ footprint would be reduced by a factor of ∼6 for a similar product grade. Based on the higher product grades achieved in the RFC™ using the higher positive bias fluxes, the performance ratio would likely exceed 10-fold given the need for the mechanical cell concentrate to undergo at least one further stage of flotation.

Spindle Nanorods of CeO2 and NiS Heterointerface Coated by the NC Layer: A High-Performance Bifunctional Electrocatalyst for Water Splitting.

Currently, nickel sulfides are widely employed in the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), thanks to the narrow electronegativity difference of only 0.67 eV between nickel and sulfur. Among them, NiS stands out in terms of the OER performance; however, its HER performance and stability remain somewhat inadequate. The construction of heterogeneous interfaces can efficiently improve the HER performance and regulate the electronic structure of the NiS catalyst. CeO2 has been discovered to possess exceptional electronic modulation capabilities, which may lead to the effective enhancement of both HER and OER of the NiS catalyst. As a result, a nitrogen-doped carbon-coated CeO2-NiS heterogeneous interface catalyst (NC/NiS-CeO2) is designed as a bifunctional electrocatalyst for HER and OER with high performance. The NC/NiS-CeO2 catalyst demonstrates excellent HER (47 mV at 10 mA cm-2) and OER (92 mV at 10 mA cm-2) performances in a 1 M KOH alkaline solution. Characterization analysis reveals that the coupling of the heterostructure interface, which consists of CeO2 and NiS, significantly enhances electron conduction, the synergistic effect, and the electrocatalytic activity of the electrode. This study demonstrates that the HER and OER activity can be effectively improved by constructing a rational heterogeneous interface.