Construction of Co-decorated 3D nitrogen doped-carbon nanotube/Ti3C2Tx-MXene as efficient hydrogen evolution electrocatalyst

Rational design of transition metal catalysts with robust and durable electrocatalytic activity for hydrogen evolution reactions (HER) is extremely important for renewable energy conversion and storage, as well as water splitting. Heteroatom doping has emerged as a feasible strategy for enhancing electrocatalytic activity. Here, cobalt nanoparticles (Co-NPs) were coated with nitrogen-doped carbon nanotubes (NCNTs) prepared via an in situ growth on accordion-like Ti₃C₂T_x-MXene (Co-NCNT/Ti₃C₂T_x). Such an intriguing structure showed great features: abundant anchoring sites for NCNT in situ growth, intimate integration of Co-NPs and NCNTs, high-speed electron transfer between 1D NCNTs and 2D Ti₃C₂T_x-MXenes, and a large number of effective catalytic active sites. This Co-NCNT/Ti₃C₂T_x hybrid catalyst was demonstrated to possess excellent HER performance with low overpotential (η₁₀, 190 mV), small Tafel slope (78.4 mV dec⁻¹), large electrochemically active surface area, and good long-term stability, thus outperforming many reported electrocatalysts. The present strategy provided a facile route for the design of transition metal HER catalysts with NCNT and MXene.     

Ti3C2Tx nanosheets with uniformly anchored Ru nanoparticles for efficient acidic and basic hydrogen evolution reaction

Developing an efficient and stable electrocatalyst for hydrogen evolution reaction (HER) remains critically signi?cance for renewable hydrogen production. Herein, a facile electrochemical reduction method was proposed to fabricate Ru nanoparticles (NPs) evenly anchored on Ti₃C₂T_x nanosheets (Ti₃C₂T_x-NS) electrocatalyst (Ru@Ti₃C₂T_x-NS). Interestingly, owing to the interaction between Ru NPs and Ti₃C₂T_x-NS, the resultant Ru@Ti₃C₂T_x-NS electrocatalyst performed a Pt-like electrocatalytic property for HER under the acidic solution with an ultra-low overpotential of 46.75 mV to reach ?10 mA/cm², a small Tafel slope of 30.6 mV/dec, and long-term stability. Simultaneously, the Ru@Ti₃C₂T_x-NS also displayed splendid HER electrocatalytic performance in the basic condition. Furthermore, Ru@Ti₃C₂T_x-NS showed a lower value of Gibbs free energy for HER (?0.21 eV) than either pure Ru or Ti₃C₂T_x-NS from the theoretical calculation results. It is expected that such a promising approach would be extended to design and fabricate other noble metal NPs anchored MXene nanosheets for HER application.     

Ultrafine Ru nanoparticles derived from few-layered Ti3C2Tx MXene templated MOF for highly efficient alkaline hydrogen evolution

It is meaningful to search high-efficient and inexpensive electrocatalysts for hydrogen evolution reaction (HER) due to the energy crisis and environmental pollution. Here, we report the preparation of ultrafine Ru nanoparticles from a hybrid of ZIF-L(Co) MOF and polydopamine coated few-layered Ti₃C₂T_x MXene (FL-Ti₃C₂T_x). FL-Ti₃C₂T_x is used as a template to grow regular leaf-shaped ZIF-L(Co) nanosheets through the reaction of Co ions anchored on the MXene surface with 2-methylimidazole. The obtained hybrid is then doped with Ru ions through ion exchange between Ru and Co ions, followed by thermal annealing at a temperature of 350 °C in an Ar atmosphere to produce ultrafine Ru nanoparticles. The obtained Ru@ZIF-L(Co)/FL-Ti₃C₂T_x nanocomposite shows outstanding HER performance with a low overpotential of 16.2 mV at a current density of 10 mA cm^?2, a small Tafel slope of 21.0 mV dec^?1 and excellent stability in 1.0 M KOH solution. This work provides a new strategy for the design and synthesis of highly efficient HER catalyst via MOFs with tunable composition and structure.     

S-doped multilayer niobium carbide (Nb4C3Tx) electrocatalyst for efficient hydrogen evolution in alkaline solutions

Developing highly efficient and low cost electrocatalysts for hydrogen evolution reaction (HER) is a popular topic for electrocatalytic water splitting to hydrogen technology. Herein, we report a novel heterostructure electrocatalyst prepared by the S-doping multilayer niobium carbide (S-ML-Nb₄C₃T_x) through hydrothermal technique. Compared with pristine ML-Nb₄C₃T_x catalyst, the as prepared electrocatalyst presents remarkable catalytic activity for HER with lower overpotential of 118 mV@10 mA/cm² and a Tafel slope of 104 mV dec^?1 in 1.0 M KOH solution. In addition, the catalyst exhibits a stable electrochemical durability of as long as 24 h in 1.0 M KOH. Efficient HER ability of the S-ML-Nb₄C₃T_x catalyst is mainly attributed to the following points: Firstly, the ML-Nb₄C₃T_x with superior conductivity and stability can effectively avoid the aggregation and oxidation. Secondly, the conversion of fluorine termination groups to –OH by TMAOH treatment can expose more active sites. Further, after the S-doping by hydrothermal reaction, NbS₂ nanoparticles can prevent the ML-Nb₄C₃T_x nanosheets from restacking. As a result, the enlarged interlayer spacing and porous structure of the catalyst are conducive to the charge transfer. In addition, the introduction of NbS₂ nanoparticles on the surface of ML-Nb₄C₃T_x can form heterostructure and subsequently adjust the electronic structure of the catalyst, accelerate the electron transfer, and improve the HER performance. This work presents a new strategy for the designing and preparation of low cost MXene-based catalysts for HER application.     

MoS2/Mo2TiC2Tx supported Pd nanoparticles as an efficient electrocatalyst for hydrogen evolution reaction in both acidic and alkaline media

Development of electrocatalytic hydrogen production technology is the key to solving environmental and energy problems. Two-dimensional material Mo₂TiC₂T_x (T_x = –OH, –F) has shown great potential in electrocatalytic hydrogen evolution because of its excellent conductivity and hydrophilicity. However, due to the lack of sufficient active sites of Mo₂TiC₂T_x itself, its practical applications in electrocatalytic hydrogen evolution are limited. In this work, a highly-efficient hydrogen evolution electrocatalyst, namely Pd@MoS₂/Mo₂TiC₂T_x, is prepared through a simple pyrolysis method. In such a composite, the MoS₂ nanoflowers hybridized with the ammonia-treated Mo₂TiC₂T_x (MoS₂/Mo₂TiC₂T_x) are used as a substrate for loading a small number of Pd nanoparticles (4.27 at.%). Notably, the introduction of Pd nanoparticles into MoS₂/Mo₂TiC₂T_x provides abundant active sites for the hydrogen evolution reaction, improves the conductivity of the electrocatalyst, speeds up the adsorption and desorption of hydrogen, and induces a synergistic effect with the MoS₂. As a result, the Pd@MoS₂/Mo₂TiC₂T_x catalyst exhibits excellent electrocatalytic performance and remarkable stability in both acidic and alkaline media. In a 0.5 mol/L H₂SO₄ electrolyte, the overpotential of Pd@MoS₂/Mo₂TiC₂T_x was 92 mV with a Tafel slope of 60 mV/dec at a current density of 10 mA/cm². Meanwhile, the catalyst displayed an overpotential of 100 mV associated with a Tafel slope of 80 mV/dec at the current density of 10 mA/cm² in a 1 mol/L KOH electrolyte. This work shows the great potential of using Mo₂TiC₂T_x-based material in the field of electrocatalysis.     

Ru–MoS2@PPy hollow nanowire as an ultra-stable catalyst for alkaline hydrogen evolution reaction

Electrocatalytic hydrogen evolution reaction (HER) is one of the green and effective method to produce clean hydrogen energy. However, the development of non-Pt HER catalysts with excellent catalytic activity and long-term stability still remains a great challenge. Herein, a vertically aligned core-shell structure material with hollow polypyrrole (PPy) nanowire as a core and Ru-doped MoS₂ (Ru–MoS₂) nanosheets as a shell is firstly reported as a highly efficient and ultra-stable catalyst for HER in alkaline solutions. Results indicate that Ru–MoS₂@PPy catalyst demands a low overpotential of 37 mV at 10 mA cm^?2. In addition, the overpotential at 100 mA cm^?2 is 157 mV and it is almost unchanged after 40,000 cyclic voltammetry cycles. The existence of PPy core not only ensures the vertical growth of MoS₂ nanosheets to expose more edge sites, but also promotes the rapid transfer of electrons, contributing to the improvement of catalytic activity. More importantly, the strong interface interaction between MoS₂ and PPy prevents the collapse of the vertical structure of MoS₂ sheets in the electrocatalytic process and greatly enhances the stability of catalysts, which offers an effective strategy to design and synthesize the HER catalysts with superior catalytic stability.     

Fabrication of phosphorus-mediated MoS2 nanosheets on carbon cloth for enhanced hydrogen evolution reaction

Molybdenum sulfide (MoS₂) as a graphene-like sheet material has attracted wide attention owing to the potential for hydrogen evolution reaction (HER). However, the large-scale application of MoS₂ is still difficult due to the inherent poor conductivity and insufficient active edge sites. Herein, we develop a simple method to grow P-doped MoS₂ nanosheets on carbon cloth for high efficiency HER. The 2D carbon cloth can prevent the stacking of MoS₂ nanosheets and improve the conductivity with the doping of P atoms. As a result, the P–MoS₂/CC-300 shows the excellent electrocatalytic activity with an overpotential of 81 mV at 10 mA cm^?2 and the lower Tafel slope of 98 mV/dec. Furthermore, it also shows the good electrocatalytic durability for 15 h. This work provides an opportunity for the design of excellent and robust MoS₂-based catalyst via structural engineering and doping method.     

NiFe LDH/Ti3C2Tx/nickel foam as a binder-free electrode with enhanced oxygen evolution reaction performance

In this work, NiFe LDH/Ti₃C₂T_x/Nickel foam (NF) was successfully prepared as a binder-free electrode by depositing NiFe layered double hydroxide (LDH) nanosheets on Ti₃C₂T_x/NF substrate through electrodeposition approach. The strong electrostatic interactions between the negatively charged surface of MXene and positively charged NF substrate enabled the direct growth of NiFe LDH nanosheets on Ti₃C₂T_x/NF substrate. As a result, the as-prepared NiFe LDH/Ti₃C₂T_x/NF electrode exhibited an excellent OER performance, fast catalytic reaction kinetics and good chemical stability. Its overpotential reached 200 mV at a current density of 10 mA cm^?2, and the cycling tests suggested a good cycling stability.     

A feasible and environmentally friendly method to simultaneously synthesize MoS2 quantum dots and pore-rich monolayer MoS2 for hydrogen evolution reaction

MoS₂ has been one of a widely researched hydrogen evolution reaction (HER) catalyst materials in recent years. However, the basal plane of MoS₂ is considered to be inactive to hinder its further development. Herein, a new mass-scalable and facile intercalation method for the fabrication of multiple products, including pore-rich monolayer MoS₂ (PR MoS₂) and MoS₂ quantum dots (MoS₂ QDs), has been developed via the gas phase etching of bulk MoS₂ in an acetone vapor atmosphere. The obtained monolayer MoS₂ QDs with a narrow lateral size distribution (average size: 2.5 nm) present excitation-independent photoluminescence emission. Furthermore, the PR MoS₂ shows a significantly enhanced HER electrocatalytic activity and good stability in 0.5 M H₂SO₄ solution with a small overpotential of 241 mV at a current density of 10 mA cm⁻². These results demonstrate that the as-prepared PR MoS₂ is very promising for the application in HER.     

MoS2/Ti3C2 heterostructure for efficient visible-light photocatalytic hydrogen generation

The MoS₂/Ti₃C₂ catalyst with a unique sphere/sheet structure were prepared by hydrothermal method. The MoS₂/Ti₃C₂ heterostructure loading 30% Ti₃C₂ has a maximum hydrogen production rate of 6144.7  μmol g⁻¹ h⁻¹, which are 2.3 times higher than those of the pure MoS₂. The heterostructure maintains a high catalytic activity within 4 cycles. The heterostructure not only effectively reduce the recombination of photogenerated electrons and holes, but also provide more activation sites, which promotes the photocatalytic hydrogen evolution reaction (HER). These works can provide reference for the development of efficient catalysts in photocatalytic hydrogen evolution.     

Defective-MoS2/rGO heterostructures with conductive 1T phase MoS2 for efficient hydrogen evolution reaction

As a two-dimensional material, molybdenum disulfide (MoS₂) exhibits great potential to replace metal platinum-based catalysts for hydrogen evolution reaction (HER). However, poor electrical conductivity and low intrinsic activity of MoS₂ limit its application in electrocatalysis. Herein, we prepare a defective-MoS₂/rGO heterostructures material containing 1T phase MoS₂ and evaluate its HER performance. The experimental results shown that defective-MoS₂/rGO heterostructures exhibits outstanding HER performance with a low overpotential at 154.77 mV affording the current density of 10 mA cm^?2 and small Tafel slope of 56.17 mV dec^?1. The unique HER performance of as-prepared catalyst can be attributed to the presence of 1T phase MoS₂, which has more active sites and higher intrinsic conductivity. While the defects of as-prepared catalyst fully expose the active sites and further improve catalytic activity. Furthermore, the interaction between MoS₂ and rGO heterostructures can accelerate electron transfer kinetics, and effectively ensure that the obtained catalyst displays excellent conductivity and structural stability, so the as-prepared catalyst also exhibits outstanding electrochemical cycling stability. This work provides a feasible and effective method for preparation of defective-MoS₂/rGO heterostructures, which also supplies a new strategy for designing of highly active and conductive catalysts for HER.     

Tuning of electrocatalytic activity of mixed metal dichalcogenides supported NiMoP coatings for alkaline hydrogen evolution reaction

The mixed metal dichalcogenides combination of WS₂–MoS₂ was coated onto Cu substrate by electroless NiMoP plating technique and the electrocatalytic hydrogen evolution reaction (HER) performance was investigated. The enhanced structural, morphological parameters and boosted electrocatalytic performance of the various metal-metal molar ratio of WS₂–MoS₂ onto NiMoP plate were identified under variable operating conditions and it was successfully evaluated by various characterization techniques. The well-defined crystalline nature, phase, particle size, structure, elemental analysis and surface morphology of prepared coatings were analyzed by FESEM, XRD, AFM and EDS mapping. The electrochemical analysis was performed using open circuit potential (OCP) analysis, chronoamperometry (CA), electrochemical impedance spectroscopy (EIS), Tafel curves, linear sweep voltammetry (LSV), cyclic voltammetry (CV) and polarization studies to find the activity of prepared electrocatalyst towards electrochemical hydrogen evolution reactions. The performance of bare NiMoP and WS₂–MoS₂/NiMoP plates were compared and found that the HER activity of NiMoP can be reinforced by composite incorporation through the synergic effect arises with in the catalytic system, which improves surface roughness and enhances the magnitude of electrocatalyst toward HER. The achievement of enhanced catalytic performance of coatings was authenticate by the kinetic parameters such as decreases in Tafel slope (98 mV dec^?1), enhanced exchange current densities (9.32 × 10^?4 A cm^?2), and a lower overpotential. The consistent performance and durability of the catalyst were also investigated. The enhanced electrocatalytic activity of WS₂–MoS₂/NiMoP coatings increased with respect to the surface-active sites associated with combination of mixed dichalcogenides and the synergic effect arises in between different components present in the coating system. This work envisages the progressive strategies for the economical exploration of a novel WS₂–MoS₂/NiMoP water splitting catalyst used for large scale H₂ generation. The prepared WS₂–MoS₂/NiMoP embedded Cu substrate possess high catalytic activity due to its least overpotential of 101 mV at a benchmark current density of 10 mA cm^?2, which demonstrated the sustainable, efficient and promising electrocatalytic property of prepared catalyst towards HER under alkaline conditions.     

Enhancing the electrocatalytic water splitting efficiency for amorphous MoSx

Amorphous molybdenum sulfide (MoS_x) materials have been considered as cheap and promising catalysts for hydrogen evolution reaction (HER). In this contribution, we report that the amorphous MoS_x catalysts prepared by the low temperature thermolysis of the (NH₄)₂MoS₄ precursors on carbon clothes (catalyst loading: 3.2 mg/cm²) exhibit a Tefal slope of 50.5 mV/dec and a high exchange current density of 1.5 × 10⁻³ mA/cm² in 0.5 M H₂SO₄ solutions. Spectroscopic studies of the amorphous MoS_x catalysts show that the increase of HER efficiency is positively correlated to the concentration of S₂²⁻ species, providing strong evidence to support the argument that S₂²⁻ is an active species for electrocatalytic HER. Additionally, the method for preparing catalysts is simple, scalable and applicable for large-scale production.     

Efficient hydrogen evolution electrocatalysts from LixMoS2 nanoparticles on three-dimensional substrate

Molybdenum disulfide (MoS₂), as a promising catalyst, has been widely investigated for hydrogen evolution reaction (HER). But the low density and poor reactivity of active sites, poor electrical transport, and inefficient electrical contact to the catalyst, leads to the modest performance. In this work, we demonstrate an effective route to overcome those issues by decorating the conductive Li_xMoS₂ nanoparticles on the three-dimensional carbon fiber paper (CFP) through combining hydrothermal method and lithium intercalation. Thus, the dense Li_xMoS₂ nanoparticles of the surface can provide the large number of exposed active sites, the highly-conductive Li_xMoS₂ nanoparticles and CFP substrate can facilitate the transfer of electron not only between the Li_xMoS₂ nanoparticles and CFP, but also between the whole sample and current collector, and the porous networked structure can enable the diffusion and penetration of electrolyte. Prompted by those advantage, the as-prepared samples exhibit outstanding HER catalytic activity with the small Tafel slope of 62 mv dec^?1 and the low overpotential of ?115.6 mV vs RHE at an electrocatalytic current density of 10 mA cm^?2. Chronoamperometric current test for 10 h confirms the long-term stability of the catalyst.     

In situ growth of MoS2 on carbon nanofibers with enhanced electrochemical catalytic activity for the hydrogen evolution

Developing an effective and facile method to achieve mass production of MoS₂ nanostructures with abundant of edges may be the feasible way to meet the increasing demand for hydrogen evolution electrocatalysts. We developed a facile glucose-assisted hydrothermal method to in-situ grow MoS₂ nanosheets on the commercial carbon nanofibers (CNFs). The controlled growth of MoS₂ on CNFs (MoS₂@CNFs) is leveraged to reveal mass ratio- and structure-dependent catalytic activity in the hydrogen evolution reaction (HER). Due to the unique shell structure, abundant edges of the MoS₂ layer are exposed as active site, as well as the underlying CNFs effectively improves the conductivity, the resulting MoS₂@CNFs hybrid exhibited high electrocatalytic activity in HER. The catalyst demonstrated the lowest overpotential of 52 mV, the highest current density of 101.49 mA cm^?2 at ～200 mV overpotential and the smallest Tafel slope of 49 mV/decade, suggesting the Volmer–Heyrovsky mechanism for the MoS₂-catalyzed HER.     

Facile synthesis of cobalt modified 2D titanium carbide with enhanced hydrogen evolution performance in alkaline media

2D transition metal carbides, nitrides and carbonitrides, namely the MXenes, attract more and more attentions due to their unique properties. Here, we report a simple one-step molten salt etching method to prepare Co modified MXene hybrid (Ti₃C₂T_x:Co) by the reaction of Ti₃AlC₂ with Lewis acid CoCl₂ at 750 °C. Most of Co atoms aggregates in the interlayered space of Ti₃C₂T_x. Benefitting from the improved electron charge transfer efficiency and increased active sites, the sulfuric acid treated Ti₃C₂T_x:Co-12h hybrid exhibits excellent electrocatalytical activity for hydrogen evolution reaction in alkaline media, delivering a current density of 10 mA cm⁻² at an overpotential of 103.6 mV, which is lower than most noble metal free MXene based electrocatalysts. The results illustrate that the proposed method is very facile and useful to incorporate mid-to-late transition metals into the MXene phase to prepare MXene based HER electrocatalysts.     

Three-dimensional ZnCo/MoS2–Co3S4/NF heterostructure supported on nickel foam as highly efficient catalyst for hydrogen evolution reaction

Exploring inexpensive and earth-abundant electrocatalysts for hydrogen evolution reactions is crucial in electrochemical sustainable chemistry field. In this work, a high-efficiency and inexpensive non-noble metal catalysts as alternatives to hydrogen evolution reaction (HER) was designed by one-step hydrothermal and two-step electrodeposition method. The as-prepared catalyst is composed of the synergistic MoS₂–Co₃S₄ layer decorated by ZnCo layered double hydroxides (ZnCo-LDH), which forms a multi-layer heterostructure (ZnCo/MoS₂–Co₃S₄/NF). The synthesized ZnCo/MoS₂–Co₃S₄/NF exhibits a small overpotential of 31 mV and a low Tafel plot of 53.13 mV dec^?1 at a current density of 10 mA cm^?2, which is close to the HER performance of the overpotential (26 mV) of Pt/C/NF. The synthesized ZnCo/MoS₂–Co₃S₄/NF also has good stability in alkaline solution. The excellent electrochemical performance of ZnCo/MoS₂–Co₃S₄/NF electrode originates from its abundant active sites and good electronic conductivity brought by the multilayer heterostructure. This work provides a simple and feasible way to design alkaline HER electrocatalysts by growing heterostructures on macroscopic substrates.     

Boosting electrochemical hydrogen evolution activity of MoS2 nanosheets via facile decoration of Au overlayer

--Owing to its unique physicochemical properties, two-dimensional (2D) layered MoS₂ has been proposed as a potential catalyst for efficient hydrogen evolution reaction (HER). However, their large-scale application is still hindered due to limited active sites, poor conductivity, and restacking during synthesis. Herein, we report a one-step hydrothermal route to grow MoS₂ nanosheets on molybdenum (Mo) foil substrate followed by Au decoration as an active cocatalyst to enhance the HER performance of MoS₂ nanosheets. A facile, quick, and controlled decoration of stable Au overlayer with different mass loadings was performed using a sputtering Au coating unit for different deposition times (10s, 30s, and 50s), thus paving the way for producing efficient and inexpensive HER electrocatalysts. Electrochemical studies of different Au–MoS₂/Mo hybrids demonstrate that the optimized Au–MoS₂/Mo-30s sample exhibits ultralow onset potential (52 ± 2 mV vs. RHE), small overpotentials of 136 ± 6 and 318 ± 3 mV (vs. RHE) at current densities of 10 and 100 mA cm^?2, a small Tafel slope (46.23 ± 6 mV/dec), along with an outstanding electrochemical stability over a couple of days. Presence of metallic 1T-phase of MoS₂, as well as the synergistic effect between MoS₂ and Au, result in enhanced electrical conductivity, high density of active sites, large electrochemically accessible surface area, and fast charge transfer at the catalyst-electrolyte interface for boosting HER activity of the hybrid catalyst.     

Highly efficient electrocatalytic hydrogen production via MoSx/3D-graphene as hybrid electrode

Molybdenum sulfide (MoS_x) has recently emerged as a promising catalyst for the hydrogen evolution reaction (HER) in water splitting that may replace the noble metal, such as platinum, as a cost-effective and high catalytic materials. It has been reported that two-dimensional structured MoS_x exhibit significant amount of exposed S-edge, which can be an active electrocatalytic catalyst for hydrogen production. However, the current reports mainly focusing on the planar electrode, where the catalyst utilization and the number of active sites are limited due to the lower exposed specific surface area (SSA) of supporting electrodes. In this work, we utilize the freeze-drying method to produce a porous three-dimensional (3D) structure assembled by graphene flakes. The as-prepared 3D graphene scaffold shows high surface area, high porosity while low density, which makes it as an ideal conductive electrode for supporting of MoS_x catalysts. Moreover, it was found out that the crystallinity of MoS_x, controlled by thermolysis temperature of thiosalts precursor ((NH₄)₂MoS₄), shows significantly influence the performance of HER. The optimized annealing temperature for the designed hybrid electrodes (MoS_x/3D-graphene) was found to create a lot of active sites, which facilitate the electrocatalytic performance for water splitting (overpotential of 163 mV @10 mA/cm² and a Tafel slope of 41 mV/dec). The study provides a potential material, which could pave the way for future applications of hydrogen energy.     

Hierarchical MoS2 nanosheets integrated Ti3C2 MXenes for electrocatalytic hydrogen evolution

In this study, conductive Ti₃C₂ MXenes were used as a promoter to accelerate charger transfer of MoS₂, realizing highly efficient HER electrocatalysis. A facile hydrothermal strategy is demonstrated to be effective for in situ growth of MoS₂ nanosheets vertically standing on planar Ti₃C₂ nanosheets to form hierarchical heterostructures. Beneficial from the opened layer structures and strong interfacial coupling effect, the resulting MoS₂/Ti₃C₂ heterostructures achieve a giant enhancement in HER activity compared with pristine MoS₂ nanosheets. More specifically, the catalytic current density induced by MoS₂/Ti₃C₂ heterostructures at an overpotential of ∼400 mV is nearly 6.2 times as high as that of the pristine MoS₂ nanosheets. This work uncovers that the Ti₃C₂ nanosheets are ideal candidates for construction of highly active electrocatalysts for water splitting.