Enhanced OER performance of NiFeB amorphous alloys by surface self-reconstruction

The design and development of cost-effective and highly efficient oxygen evolution reaction (OER) electrocatalysts are urgently desirable during the water-splitting process. Here, Ni_xFe_80-xB₂₀ (x = 70, 60, 50, 40, 30, hereafter referred to as NFB) amorphous alloys, with high mechanical strength, excellent corrosion resistance, and unique atomic structure, are fabricated as efficient water oxidation electrocatalysts in alkaline solutions. Ni₄₀Fe₄₀B₂₀ amorphous ribbons achieve only 319 mV of overpotential at 10 mA·cm^?2 with a Tafel slope of 56 mV dec^?1 and exhibit excellent long-term stability for 24 h at 10 mA·cm^?2 and 100 mA·cm^?2 in 1 M KOH solution, which outperform the commercial RuO₂ electrocatalyst. It is worth noting that the OER performance of Ni_xFe_80-xB₂₀ amorphous electrocatalysts after long-term chronopotentiometry test displays more effectively, which can be ascribed to the surface construction. Meanwhile, the analysis of the morphology and structure of the electrocatalysts reveal that continuous oxidation during the OER process induces the structural reorganization on the surface of the electrocatalysts, which can enhance the electron transfer process and adsorption of the reaction intermediates to optimize the OER performance. This study provides a shred of evidence for surface self-reconstruction of NiFeB amorphous alloys electrocatalysts during the OER process and promotes the application of amorphous alloys as functional materials in the water-splitting field.     

In situ growth of NiCoFe-layered double hydroxide through etching Ni foam matrix for highly enhanced oxygen evolution reaction

It is of great significance to develop the nonprecious metal oxide electrocatalysts toward oxygen evolution reaction (OER) for water splitting. Herein we report an in-situ growth of the ternary NiCoFe-layered double hydroxide nanosheets on surface etching nickel foam (NiCoFe LDHs/NF) without adding any nickel precursor. In this method, etching Ni matrix by Fe³⁺ not only provides the slowly released nickel ions, but also intensifies the Fe–Ni interaction between the directly grown active species and Ni foam. Therefore the composition, electronic structure, and morphology of the electrocatalysts can be easily regulated only by adjusting Co²⁺:Fe³⁺ ratio in the precursor solution. The obtained NiCo₁Fe₁ LDH/NF, which is formed in 1:1 Co²⁺:Fe³⁺ solution, has highest content of Ni³⁺ and Co³⁺ active sites and the largest electrochemical active area. It exhibits an outstanding OER performance with a small overpotential of 231 mV at 10 mA cm^?2 and excellent durability at 50 mA cm^?2 in 1.0 M KOH solution.     

Nitrogen-doped mesoporous carbon for energy storage in vanadium redox flow batteries

We demonstrate an excellent performance of nitrogen-doped mesoporous carbon (N-MPC) for energy storage in vanadium redox flow batteries. Mesoporous carbon (MPC) is prepared using a soft-template method and doped with nitrogen by heat-treating MPC in NH₃. N-MPC is characterized with X-ray photoelectron spectroscopy and transmission electron microscopy. The redox reaction of [VO]²⁺/[VO₂]⁺ is characterized with cyclic voltammetry and electrochemical impedance spectroscopy. The electrocatalytic kinetics of the redox couple [VO]²⁺/[VO₂]⁺ is significantly enhanced on N-MPC electrode compared with MPC and graphite electrodes. The reversibility of the redox couple [VO]²⁺/[VO₂]⁺ is greatly improved on N-MPC (0.61 for N-MPC vs. 0.34 for graphite), which is expected to increase the energy storage efficiency of redox flow batteries. Nitrogen doping facilitates the electron transfer on electrode/electrolyte interface for both oxidation and reduction processes. N-MPC is a promising material for redox flow batteries. This also opens up new and wider applications of nitrogen-doped carbon.     

Ultrathin MoS2 nanosheets in situ grown on rich defective Ni0.96S as heterojunction bifunctional electrocatalysts for alkaline water electrolysis

Developing earth-abundant and highly active bifunctional electrocatalysts are critical to advance sustainable hydrogen production via alkaline water electrolysis but still challenging. Herein, heterojunction hybrid of ultrathin molybdenum disulfide (MoS₂) nanosheets and non-stoichiometric nickel sulfide (Ni_0.96S) is in situ prepared via a facile one-step hydrothermal strategy, followed by annealing at 400 °C for 1 h. Microstructural analysis shows that the hybrid is composed of intimate heterojunction interfaces between Ni_0.96S and MoS₂ with exposed active edges provided by ultrathin MoS₂ nanosheets and rich defects provided by non-stoichiometric Ni_0.96S nanocrystals. As expected, it is evaluated as bifunctional electrocatalysts to produce both hydrogen and oxygen via water electrolysis with a hydrogen evolution reaction (HER) overpotential of 104 mV at 10 mA cm⁻² and an oxygen evolution reaction (OER) overpotential of 266 mV at 20 mA cm⁻² under alkaline conditions, outperforming most current noble-metal-free electrocatalysts. This work provides a simple strategy toward the rational design of novel heterojunction electrocatalysts which would be a promising candidate for electrochemical overall water splitting.     

Cu2S/Ni3S2 ultrathin nanosheets on Ni foam as a highly efficient electrocatalyst for oxygen evolution reaction

It is an inevitable choice to find efficient and economically-friendly electrocatalysts to reduce the high overpotential of oxygen evolution reaction (OER), which is the key to improve the energy conversion efficiency of water splitting. Herein, we synthesized Cu₂S/Ni₃S₂ catalysts on nickel foam (NF) with different molar ratios of Ni/Cu by a simple two-step hydrothermal method. Cu₂S/Ni₃S₂-0.5@NF (CS/NS-0.5@NF) effectively reduces the overpotential of OER, displaying small overpotentials (237 mV@100 mA cm^?2 and 280 mV@500 mA cm^?2) in an alkaline solution, along with a low Tafel slope of 44 mV dec^?1. CS/NS-0.5@NF also presents an excellent durability at a relatively high current density of 100 mA cm^?2 for 100 h. The excellent performance is benefited by the prominent structural advantages and desirable compositions. The nanosheet has a high electrochemical active surface area and the porous structure is conducive to electrolyte penetration and product release. This work provides an economically-friendly Cu-based sulfide catalyst for effective electrosynthesis of OER.     

Three-dimensional hierarchical nanoporous (Mn,Ni)-Doped Cu2S architecture towards high-efficiency overall water splitting

Dealloying technique is an important approach to design porous structures and highly active catalysts. In this work, monolithic nanoporous (Mn,Ni)-doped Cu₂S skeletons with controllable composition and tunable porosity are synthesized via dealloying and sulfuration technique. The as-prepared S-np-Mn₇₀Cu₂₉Ni₁ electrode exhibits outstanding catalytic performance toward HER and OER in 1.0 M KOH solution, which drives high current density of 50 mA cm^?2 at the overpotentials of 136 and 317 mV respectively. The excellent catalytic performance is attributed to the unique three-dimensional interconnected bicontinuous nanoporous architecture, which not only exposes high-density catalytic active sites, but also accelerates electron/mass transfer between catalyst surface and electrolyte. Density functional theory (DFT) calculations also reveal that (Mn,Ni)-doped Cu₂S matrix can accelerate water adsorption/dissociation and optimize adsorption-desorption energetics of H intermediates, thus improving the intrinsic HER activity of nanoporous Cu₂S electrocatalysts. Meanwhile, an alkaline water electrolyzer is constructed with the S-np-Mn₇₀Cu₂₉Ni₁ electrode as anode and cathode respectively, depicting remarkable performance in water electrolysis. In the light of advantages such as adjustable composition and tunable porosity in alloying-dealloying process, it offers a new vision for tuning the porosity and catalytic activities of transition metal sulfides and other active catalysts.     

Al-doped vanadium dioxide thin films deposited by PLD

Thin films of vanadium dioxide (VO₂) and Al³⁺-doped VO₂ were deposited on silicon and glass substrates using pulsed laser deposition (PLD). Optimized processing conditions were determined for depositing pure VO₂ with monoclinic phase by laser ablation of a V₂O₅ target. Al³⁺-doping levels in the VO₂ films were varied by altering the relative laser ablation time on the Al₂O₃ and V₂O₅ targets. The change in electrical conductivity with temperature in the semiconductor to metallic phase transition was measured for pure VO₂ and Al³⁺-doped VO₂ films. Doping the VO₂ films with Al³⁺ lowered the transition temperature directly on increasing the Al³⁺ content from 67 °C for the pure VO₂ films to 40 °C at 10% Al³⁺. The magnitude of the resistance change from semiconductor to metallic states also decreased with increase in Al³⁺ doping. The results imply that Al³⁺-doped VO₂ films could be a good candidate for energy-efficient “smart window” coatings used for architecture applications.     

Remarkable electrocatalytic activity of Ni-nanoparticles on MOF-derived ZrO2-porous carbon/reduced graphene oxide towards methanol oxidation

In the present work, a porous carbonaceous platform containing zirconium oxide was used for spreading Ni nanoparticles, and applied to methanol oxidation. The platform was obtained by calcination of a metal-organic framework (MOF) attached to graphene oxide. Nickel nanoparticles were then deposited on the nanocomposite by chemical reduction from a Ni²⁺ solution. The obtained electrocatalyst was characterized by different methods. An excellent electrocatalytic behavior was observed towards methanol oxidation in alkaline medium (j ~ 240 mA cm^?2 or ~ 626 mA mg^?1 in 1.0 M methanol). The results of methanol oxidation by various electrochemical studies (cyclic voltammetry, electrochemical impedance spectroscopy, chronoamperometry and chronopotentiometry) revealed the effective synergy between reduced graphene oxide, porous carbon material, ZrO₂ metal oxide and Ni nanoparticles. Good durability and stability of the proposed electrocatalyst and significantly increased current density of methanol oxidation suggest it as a potential alternative for Pt-based electrocatalysts in direct methanol fuel cells.     

Stainless steel mesh-based CoSe/Ni3Se4 heterostructure for efficient electrocatalytic overall water splitting

The construction of high-efficiency bifunctional electrocatalysts is still a main challenge for hydrogen production from water splitting, in which comprehensive structure regulation plays a key role for synergistically boosting the intrinsic activity and charge collection. Here, we used a two-step hydrothermal method for construction of an interjaculated CoSe/Ni₃Se₄ heterostructure from NiCo LDH nanosheets grown on stainless steel (SS) meshes as bifunctional electrocatalysts for overall water splitting. The SS meshes containing Fe and Ni act as an excellent 3D scaffold for catalyst growth and charge collection. The SS@CoSe/Ni₃Se₄ composite exhibits outstanding electrocatalytic performances with low overpotentials of 97 mV for hydrogen evolution and 230 mV for oxygen evolution to reach a current density of 10 mA cm⁻², respectively. Moreover, by using SS@CoSe/Ni₃Se₄ as both the cathode and anode, the assembled electrolyze only required 1.55 V to reach 10 mA cm⁻² for overall water splitting. The outstanding performance of SS@CoSe/Ni₃Se₄ benefits from the synergy between excellent charge collection capability of SS meshes and the abundant active sites at the CoSe/Ni₃Se₄ heterointerface formed with the in-situ conversion of NiCo LDH nanosheets. Electrochemical active surface area and impedance spectrum indicate that the CoSe/Ni₃Se₄ loaded on SS has the most abundant electrochemically active sites and the smallest electrochemical resistance, thereby exposing more active sites and enhancing the charge transfer to promote the catalytic activity. By integrating the delicate nanoscale heterostructure engineering with the microscale SS mesh scaffold, our work provides a new perspective for the preparation of high-performance and cheap electrocatalysts that are easy to be integrated with industrial applications.     

Chromium doping and in-grown heterointerface construction for modifying Ni3FeN toward bifunctional electrocatalyst toward alkaline water splitting

Exploring high-performance non-noble metal electrocatalysts is pivotal for eco-friendly hydrogen energy applications. Herein, featuring simultaneous Chromium doping and in-grown heterointerface engineering, the Cr doping Ni₃FeN/Ni heterostructure supported on N-doped graphene tubes (denoted as Cr–Ni₃FeN/Ni@N-GTs) was successfully constructed, which exhibits the superior bifunctional electrocatalytic performances (88 mV and 262 mV at 10 mA cm⁻² for HER and OER, respectively). Furthermore, an alkaline electrolyzer, employing Ni₃FeN/Ni@N-GTs as both the cathode and the anode, requires a low cell voltage of 1.57 V at 10 mA⋅cm⁻². Cr doping not only modulates the electronic structure of host Ni and Fe but also synchronously induces nitrogen vacancies, leading to a higher number of active sites; the in-grown heterointerface Cr–Ni₃FeN/Ni induces the charge redistribution by spontaneous electron transfer across the heterointerface, enhancing the intrinsic catalytic activity; the N-GTs skeleton with excellent electrical conductivity improves the electron transport and mass transfer. The synergy of the above merits endows the designed Cr–Ni₃FeN/Ni@ N-GTs with outstanding electrocatalytic properties for alkaline overall water splitting.     

Soft-template synthesis of vanadium oxynitride-carbon nanomaterials for supercapacitors

By using Polyvinylpyrrolidone (PVP) as the soft-template, vanadium oxynitride-carbon (VO_xN_y-C) nanomaterials were synthesized by NH₃ reduction of V₂O₅ xerogel. The powder X-ray diffraction result indicated that the VO_xN_y-C belongs to the cubic crystal system. Transmission electron microscopy (TEM) images showed that most of the VO_xN_y grains in VO_xN_y-C materials were lower than 20 nm. Electrochemical test results showed that VO_xN_y-C materials exhibited better conductivity and enhanced electrochemical properties compared to VO_xN_y materials which were synthesized only by NH₃ reduction of V₂O₅ xerogel. The maximum specific capacitance of VO_xN_y-C electrode reaches up to 271 Fg⁻¹ at 1 Ag⁻¹ which is much higher than that of VO_xN_y electrode (143 F g⁻¹). The specific capacitance of VO_xN_y-C electrode lost less than 10% as the scan rate increased 20 times from 5 to 100 mV s⁻¹, showing its superior rate capability. The VO_xN_y grains and remaining carbon were intimate contact each other in VO_xN_y-C nanocomposite which results in a better electronic conductivity, as well as the high surface area which furnishes more surface active redox sites of VO_xN_y-C nanocomposite. Therefore, VO_xN_y-C material exhibited better electrochemical performance than VO_xN_y. Cycle tests showed that restricting the potential window can improve the cycling stability of the VO_xN_y-C electrode. This cycle phenomenon may be ascribed to the use of high upper potentials which lead to the irreversible oxidation of electrode materials and the concomitant formation of soluble vanadium based species, which further result in the reduction of the active redox sites, and ultimately enhance the electrode's irreversibility in 1 M KOH.     

Construction of nickel selenides heterointerfaces with electron redistribution for solar-driven water splitting

Developing heterostructures electrocatalysts was a promising method to improve the water splitting efficiency. However, due to the difficulty of synthesis, such low-cost and high-activity heterostructures electrocatalysts have not been developed. In this work, Ni₃Se₂/NiSe heterostructure nanosheets with rich-phase boundaries were synthesized by soaking at room temperature and annealing treatment using nickel foam as both Ni source and substrate. Such a nanosheet-like Ni₃Se₂/NiSe heterostructure could expose more active sites and efficient mass transfer at solid-liquid-gas three-phase interfaces, which exhibits a lower overpotential of 336 mV at 100 mA cm⁻² and exceptional stability over 80 h at the current density of 300 mA cm⁻² for OER in alkaline solution. Furthermore, the heterostructures electrode implements solar-driven water with a high solar-to-hydrogen efficiency of 18.3%. This heterostructure strategy might be a major breakthrough for improving the transition metal selenides and designing high-active and stable catalysts for electrochemical water oxidation.     

Coaxial Ni3S2@CoMoS4/NiFeOOH nanorods for energy-saving water splitting and urea electrolysis

High efficiency and energy-saving electrochemical hydrogen production has always been a research challenge, mainly due to the limitation of the sluggish kinetics of anodic reactions. Excellent performance depends largely on the clever design of nano-architectures and smart hybridization of active components. It is also very important to establish the relationship between structure and performance of materials. Form perspectives of chemical composition and nanostructure, we developed a novel heterostructure of Ni₃S₂@CoMoS₄/NiFeOOH coaxial nanorods on NF scaffold, in which the two-dimensional CoMoS₄ nanoplates and ultrathin NiFeOOH nanosheets vertically coil around the Ni₃S₂ nanorods by hydrothermal reaction combined with electrodepostion process. Such hierarchical nanorods can provide the heterointerface with highly open surface, ensuring the maximization of synergistic interaction. This heterostructure results in prominent bifunctional activity for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline water electrolysis systems, and HER coupled with urea oxidation reaction in urea electrolysis devices. It exhibits very low cell voltages for alkaline water splitting (1.732 V) and urea electrolysis (1.660 V) to afford a current density of 100 mA cm^?2 in the two-electrode system as well as excellent long-term stability. Our work provides a new construction for combining various active materials to competitive bifunctional electrocatalysts applied in energy-relative electrochemical devices.     

Natural-wood-fiber-assisted synthesis of Ni2P embedded in P-doped porous carbon as highly active catalyst for urea electro-oxidation

Defect and interface engineering has been established as efficient methods for altering the electrical structure and improving the activity of electrocatalysts. Here, a rational design architecture consisting of Ni₂P nanoparticles embedded in P-doped carbonized wood fibers (Ni₂P/PCWF) is synthesized by simultaneous carbonization and phosphorization. A synergistic enhancement effect between electronic structure manipulation and interface regulation is observed in Ni₂P/PCWF during the urea oxidation reaction (UOR). First, the P doping of carbon can optimize the electronic structure of Ni₂P/PCWF. Second, the charge transport process is aided by the Ni₂P nanoparticles embedded in the PCWF. Lastly, electron transfer can be accelerated by the in-situ formed heterogeneous interface between metal phosphides and metal hydroxides (hydroxyl oxides). Due to the synergy of the structural and electrical modulation, Ni₂P/PCWF exhibits remarkable electrocatalytic properties toward the UOR under alkaline conditions. It only requires 1.34 V (vs. RHE) to achieve a current density of 50 mA cm^?2, and the increase in potential at 10 mA cm^?2 for 70 h is insignificant (≈2.9%). This work supports the development of new strategies using sustainable, renewable wood fibers to develop excellent UOR catalysts for energy-saving H₂ generation.     

Facile synthesis of bimetallic Ni–Fe phosphide as robust electrocatalyst for oxygen evolution reaction in alkaline media

Bimetallic Ni–Fe phosphide electrocatalysts were in-situ synthesized through direct phosphorization of metal salts on carbon cloth (CC). The Fe dopant remarkably enhances the OER performance of Ni₂P in alkaline medium through the electronic structure modulation of Ni. The (Fe_0.5Ni_0.5)₂P/CC electrode, composed of uniform films coated on carbon fibers, delivers a low overpotential of 260 mV with a small Tafel slope of 45 mV·dec⁻¹ at the current density of 100 mA cm⁻², outperforming most reported non-noble electrocatalysts and commercial RuO₂ electrocatalyst. The (Fe_0.5Ni_0.5)₂P/CC also displays superior electrochemical stability at high current density. An appropriate Fe dopant level facilitates the in-situ transformation of Ni–Fe phosphides into active NiFeOOH during alkaline OER. This work simplifies the synthesis procedure of metal phosphides.     

Nanocubic bimetallic organic framework self-templated from Ni precursor as efficient electrocatalysts for oxygen evolution reaction

Developing highly active and robust oxygen evolution reaction electrocatalysts is indispensable to relieve energy crisis. Herein, firstly, the Ni nanocubes precursor as a self-sustaining template is synthesized through a reflow method. Afterward, the nanocubic NiFe bimetallic organic frameworks was formed under the self-assembly approach between the exogenous Fe²⁺ and released Ni²⁺ from Ni nanocubes with terephthalic acid organic ligand on the Ni nanocubes precursor, i.e Ni nanocubes@MIL-53(NiFe). The synthesized Ni nanocubes@MIL-53(NiFe) exhibit excellent activity, which only requires the overpotential of 271 and 388 mV to deliver the current density of 20 and 100 mA cm⁻² in alkaline solution (1.0 M KOH). The noticeable catalytic performance can be ascribed to the aspects as following: 1) Ni nanocubes as a template provides a Ni source during the self-assembled process; 2) the metal-metal coupling effect arisen within the Ni and Fe atom is substantially contributed to the oxygen evolution reaction performance; 3) the abundant active sites, enhanced electron transport ability also endow the superior electrocatalytic oxygen evolution reaction activity; 4) rich carboxyl groups in the metal-organic frameworks structure could enhance the hydrophilicity of the catalysts. We anticipate that our study would extend the design and exploration of active metal-organic frameworks on energy conversion field.     

Bifunctional electrocatalysts of CoFeP/rGO heterostructure for water splitting

Bifunctional non-precious electrocatalysts with high performance are highly desired for renewable energy but remain challenging. Herein, a CoFeP/rGO heterostructure was rational developed based on the synergistic effect, including superior conductivity, increased catalytic active sites of rGO support and the regulated electron distribution of bimetallic phosphide. At a current of 10 mA cm^?2, the CoFeP/rGO-2 composite exhibits excellent HER activity with low overpotentials of 101 mV and 76 mV in 1.0 M KOH and 0.5 M H₂SO₄ electrolyte, respectively. And highly active alkaline OER performance was provided with an overpotential of only 275 mV to reach a current density of 10 mA cm^?2. By the way, the CoFeP/rGO-2 electrode showed a pleasured working voltage of 1.58 V for overall water splitting in alkaline environment. More importantly, the long term durability and higher stability of the catalysts demonstrated their feasibility of bimetallic phosphide/rGO system as bifunctional electrocatalysts.     

Crystalline nickel sulfide integrated with amorphous cobalt sulfide as an efficient bifunctional electrocatalyst for water splitting

The development of highly efficient and low-cost electrocatalysts is critical to the mass production of hydrogen from water splitting. Herein, a facile yet effective method was developed to synthesize bimetallic sulfides Ni₃S₂/CoS_x, which were aimed for use as the electrocatalysts in both HER and OER. Encouragingly, the Ni₃S₂/CoS_x demonstrated a low overpotential of 110 mV for HER at a current density of 10 mA·cm^?2. It was discovered that the surface of Ni₃S₂/CoS_x during OER process would undergo an in-situ oxidation to form MOOH (M = Co, Ni), that is, MOOH/Ni₃S₂/CoS_x were the real functioning species in catalysis, which had an excellent OER activity and a low overpotential of 226 mV. Additionally, the assembled electrolyzer required only a low cell voltage of 1.53 V to achieve a current density of 10 mA·cm^?2 in a 1 M KOH solution, and its performance was stable. Overall, this work provided a promising strategy for the facile fabrication of low-cost amorphous electrocatalysts, which is expected to promote the progress of overall water splitting.     

In situ growth of Ni0·85Se on graphene as a robust electrocatalyst for hydrogen evolution reaction

Seeking the efficient and robust electrocatalysts necessarily enhances performance of hydrogen evolution reaction (HER). Increasing the surface active sites is a means to improve the performance. Herein, we use the Ni_0·85Se anchored on reduction of graphene oxide (Ni_0·85Se/rGO) hybrid material skillfully established by one-step facile hydrothermal method as a robust and stable electrocatalyst applying to hydrogen evolution reaction (HER). In terms of morphology, Ni_0·85Se nanospheres composed of many nanosheets are uniformly distributed on the graphene sheet layer. We also detailedly analyze its properties. Based on the interaction between Ni_0·85Se and rGO, and the roles of graphene are as a substrate to heighten conductivity, possesses more active surface area by limiting growth of Ni_0·85Se, and increases dispersion for exposing more active surface area and enlarge ion/electron transfer rate. In HER, the Ni_0·85Se/rGO catalyst displays the overpotential of 128 mV with a common current density of 10 mA cm⁻², a small Tafel slope of 91 mV dec⁻¹, an extremely low onset potential of 37 mV, outstanding stability that a high current retention of 97.7% after 1000 cycles and well long-term stability for 18 h, outperforming the capability of Ni_0·85Se nanospheres in alkaline solution for HER. The above results indicate that the Ni_0·85Se/rGO hybrid material is a good HER ability and non-noble metal electrocatalyst has potential value in HER.     

Interface engineering of Ni0.85Se/Ni3S2 nanostructure for highly enhanced hydrogen evolution in alkaline solution

Interface engineering is considered as an effective strategy to improve the hydrogen evolution reaction (HER) performance of electrocatalysts. Herein, the Ni_0.85Se/Ni₃S₂ heterostructure grown on nickel foam (NF) is synthesized via successive wet-chemical processes. The obtained Ni_0.85Se/Ni₃S₂ heterostructure is firstly investigated as an HER electrocatalyst in alkaline media and exhibits more excellent electrochemical properties over Ni₃S₂. And it delivers a low overpotential of 145 mV at a current density of ?10 mA cm^?2, and superior stability. Based on the analysis of high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectra (XPS), the enhanced HER activity is due to the modulation of surface electronic structure, ascribing from the construction of heterointerface between Ni_0.85Se and Ni₃S₂. Meanwhile, the Ni_0.85Se/Ni₃S₂ heterostructure prepared in this work is also verified to be employed as a promising alternative to noble metal catalysts in HER.