Excellent Electrocatalytic Performance For Hydrogen Evolution Reaction Research Articles

In situ construction of W-doped Co-P electrocatalyst by electrodeposition for boosting alkaline water/seawater hydrogen evolution reaction

The development of an efficient yet cost-effective non-precious electrocatalyst for the hydrogen evolution reaction (HER) in alkaline water and seawater systems remains a formidable obstacle to the large-scale production of hydrogen energy, stemming from the sluggish kinetics of electron transfer reactions during the HER process. In this article, an amorphous Co-P-W electrocatalyst on nickel foam is prepared using a brief cyclic voltammetry (CV) electrodeposition method. The optimized Co-P-W electrocatalyst exhibits excellent electrocatalytic performance for HER, which only requires overpotentials of 59 and 143 mV to achieve a current density of 10 mA cm−2 in alkaline water (1.0 M KOH) and alkaline seawater (1.0 M KOH + natural seawater), respectively, and remarkable stability and durability. The improved HER performance of the Co-P-W electrocatalyst is attributed to the introduction of W, which modulates the electronic structure of Co and P, optimizes the adsorption/dissociation of H2O, and reduces the charge transfer resistance of the Co-P electrocatalyst, thus improving the kinetics of the HER. Furthermore, the W-doping significantly enhances the hydrophilicity of the Co-P electrocatalyst, which favors rapid and thorough penetration of electrolytes into the electrocatalyst, facilitating the formation of a highly accessible reaction interface, ultimately resulting in excellent HER activity. Our findings demonstrate the feasibility of designing an efficient, durable, and scalable electrocatalyst to significantly boost HER efficiency for practical water electrolysis.

Phase Engineering-Mediated D-Band Center of Ru Sites Promote the Hydrogen Evolution Reaction Under Universal pH Condition.

The rational design of pH-universal electrocatalyst with high-efficiency, low-cost and large current output suitable for industrial hydrogen evolution reaction (HER) is crucial for hydrogen production via water splitting. Herein, phase engineering of ruthenium (Ru) electrocatalyst comprised of metastable unconventional face-centered cubic (fcc) and conventional hexagonal close-packed (hcp) crystalline phase supported on nitrogen-doped carbon matrix (fcc/hcp-Ru/NC) is successfully synthesized through a facile pyrolysis approach. Fascinatingly, the fcc/hcp-Ru/NC displayed excellent electrocatalytic HER performance under a universal pH range. To deliver a current density of 10mAcm-2, the fcc/hcp-Ru/NC required overpotentials of 16.8, 23.8 and 22.3mV in 1M KOH, 0.5M H2SO4 and 1M phosphate buffered solution (PBS), respectively. Even to drive an industrial-level current density of 500 and 1000mAcm-2, the corresponding overpotentials are 189.8 and 284mV in alkaline, 202 and 287mV in acidic media, respectively. Experimental and theoretical calculation result unveiled that the charge migration from fcc-Ru to hcp-Ru induced by work function discrepancy within fcc/hcp-Ru/NC regulate the d-band center of Ru sites, which facilitated the water adsorption and dissociation, thus boosting the electrocatalytic HER performance. The present work paves the way for construction of novel and efficient electrocatalysts for energy conversion and storage.

Synthesis of Stable and Efficient Electrocatalysts for Hydrogen Evolution: Hierarchical NiMo-Based Hollow Nanotubes

Large-scale development of low-cost, efficient, and stable powder electrocatalysts for the hydrogen evolution reaction (HER) in alkaline solutions is a key step toward commercial hydrogen production. Herein, a hierarchical NiMo-MoO3-x hollow nanotube (NiMo-MoO3-x-HNT) with bifunctional groups as an efficient HER electrocatalyst was strategically invented using an MoO3 nanorod (MoO3−NR) as the precursor. The synthesis mechanism of the NiMo-MoO3-x-HNT is established based on in-depth investigations using diffraction, spectral, and microscopy results. Experimental results suggest that the NiMo-MoO3-x-HNT exhibits excellent electrocatalytic HER performance in 1 M KOH, with a low overpotential of 26.5 mV@10.0 mA cm-2 and a small Tafel slope of 32.6 mV dec–1. These values are comparable to those of cutting-edge electrocatalysts based on platinum-group metals. Moreover, it exhibits an almost unaffected cyclic stability over 50,000 cycles and robust durability over 98 h. This remarkable performance is attributed to its bifunctional groups and the porous hierarchical hollow nanotubular morphology. In summary, this study proposes a novel, efficient, and cost-effective strategy for the development of noble metal-free, high-performance HER electrocatalysts.

Modulating electronic structure of support for boosting H2 generation in alkaline medium

The sluggish kinetics of the hydrogen evolution reaction (HER) in alkaline media have been ascribed to the extra energy required to split water molecules and generate protons. Herein, the HER performance in an alkaline medium was enhanced by fabricating a catalyst consisting of metallic Ni on Fe-doped MoOx nanosheets (Ni/Fe-MoOx) to promote water dissociation. The Ni/Fe-MoOx catalysts only requires a low overpotentials of 36 mV and 167 mV to achieve current densities of 10 and 100 mA cm−2 in 1.0 M KOH, respectively. This is better than the performance of Ni/MoOx catalysts. The excellent electrocatalytic HER performance of Ni/Fe-MoOx can be ascribed to the stronger water dissociation ability caused by Fe doping, which was demonstrated by DFT calculations and in-situ FTIR spectra, providing more available protons in the alkaline medium. Moreover, Fe doping boosts the oxygen evolution reaction (OER) performance of the Ni/Fe-MoOx catalysts in the alkaline media via the in-situ formation of Fe doped NiOOH during the OER process. Thus, using the Ni/Fe-MoOx catalysts as both the anode and cathode in a water splitting device results in a low cell voltage of 1.50 V at a current density of 10 mA cm−2, as well as excellent stability within 24 h. This work paves a novel way for synthesis of high-performance bifunctional electrocatlysts.

Electrocatalytic performance of hetrostructured MoS2/Ag2S/Ag nanocomposites for hydrogen evolution reaction

Two-dimensional transition metal dichalcogenides and their composites are currently being developed for use as electrocatalysts. MoS2 and Ag2S are transition metal dichalcogenides that provide electrocatalytically active edge sites for the hydrogen evolution reaction (HER). Lower electrical conductivity, on the other hand, is an issue for both MoS2 and Ag2S. To increase their electrical conductivity, Ag is employed, and hybrid MoS2/Ag2S/Ag nanostructures are hydrothermally synthesized at various temperatures (160 °C, 170 °C, 180 °C, 190 °C, and 200 °C). The samples synthesized at 180 °C, 190 °C, and 200 °C, respectively, exhibited crystallinity, lower bandgap values, increased current density at bias voltages in forward and reverse biassing, and efficient electrocatalytic activity in the HER. The nanocomposite prepared at 200 °C exhibits excellent electrocatalytic performance for the HER in acidic solution, with an overpotential of 101 mV (vs. RHE) at a current density of 10 mA/cm2, a low Tafel slope of 41 mV/dec, a large active surface area, a minimum charge-transfer resistance of 41 Ω, and long-term stability. This excellent electrocatalytic performance for HER originates from the synergistic effect of MoS2 and Ag2S components with their electrocatalytically active edge sites and highly conductive Ag nanoparticles. The results give a prominent viewpoint for the hybrid MoS2/Ag2S/Ag nanocomposite as an efficient electrocatalyst for the production of hydrogen through a water-splitting reaction.

Carbon dots modified molybdenum disulfide as a high-efficiency hydrogen evolution electrocatalyst

Molybdenum disulfide (MoS2) is considered a low-cost material that may replace platinum-based electrocatalysts towards hydrogen evolution reaction (HER). However, the catalytic activity of MoS2 is limited by the low conductivity and lack of active sites. Here, a biomass carbon dots-molybdenum disulfide (BCDs-MoS2) composite was synthesized as a HER catalyst by a simple hydrothermal method. The BCDs-MoS2 catalyst displayed excellent electrocatalytic performance for HER with lower onset overpotential (115 mV), smaller Tafel slope (56.57 mV dec−1) as well as high cycling stability, which superior to those of homemade MoS2, commercial MoS2, and most of the reported MoS2-based catalysts. According to the characterization results of morphology, surface properties, and valence states of elements, the outstanding catalytic activity of BCDs-MoS2 is ascribed to its loose structure with a large specific surface area along with abundant edges and defects, and the increase in the amount of S22− and S2− which possess higher activity due to the addition of the BCDs. This study can afford a new strategy to design high performance HER catalysts.

Laser fragmentation in liquid synthesis of novel palladium-sulfur compound nanoparticles as efficient electrocatalysts for hydrogen evolution reaction

One promising way to tune the physicochemical properties of materials and optimize their performance in various potential applications is to engineer material structures at the atomic level. As is well known, the performance of Pd-based catalysts has long been constrained by surface contamination and their single structure. Here, we employed an unadulterated top-down synthesis method, known as laser fragmentation in liquid (LFL), to modify pristine PdPS crystals and obtained a kind of metastable palladium-sulfur compound nanoparticles (LFL-PdS NPs) as a highly efficient electrocatalyst for hydrogen evolution reaction (HER). Laser fragmentation of the layered PdPS crystal led to a structural reorganization at the atomic level and resulted in the formation of uniform metastable LFL-PdS NPs. Noteworthy, the LFL-PdS NPs show excellent electrocatalytic HER performance and stability in acidic media, with an overpotential of –66 mV at 10 mA⋅cm−2, the Tafel slope of 42 mV⋅dec−1. The combined catalytic performances of our LFL-PdS NPs are comparable to the Pt/C catalyst for HER. This work provides a top-down synthesis strategy as a promising approach to design highly active metastable metal composite electrocatalysts for sustainable energy applications.

Facile immobilization of polyoxometalates for low-cost molybdenum/tungsten phosphide nanoparticles on carbon black for efficient electrocatalytic hydrogen evolution

Cheap and stable earth-abundant electrocatalysts for hydrogen evolution reaction (HER) is an urgent need to realize industrial production of hydrogen. Herein, we present a “1-methylimidazole-immobilization” method to fix molybdenum and tungsten precursors simultaneously on carbon black for preparation of hybrid molybdenum/tungsten phosphide (Mo-W-P) HER catalysts. The synthesis of Mo-W-P nanoparticles on carbon black was designed as two steps: immobilization and phosphorization. The Mo/W precursors, phosphotungstic acid (H3PW12O40) and phosphomolybdic acid (H3PMo12O40) were first fixed on carbon black by 1-methylimidazole, followed by subsequent calcination in air to form the Mo-W-O precursors, which were further phosphatized with red phosphorus at 850 °C in argon atmosphere to form the Mo-W-P nanoparticles. The HER performance can be effectively tuned by changing the atomic ratio of Mo/W, where the introduction of suitable amount of W into MoP results in dramatic decrease of the overpotential. The optimized sample with Mo/W ratio of 1.8:1 showed excellent electrocatalytic performance for HER with a low onset overpotential of 92 mV, along with a low Tafel slope of 62 mV dec−1 in 0.5 M H2SO4. More importantly, at higher current density of 50 mA cm−2, the optimized Mo-W-P/CB sample showed superior overpotential (231 mV) to that of MoP/CB (287 mV) and WP/CB (333 mV). Meanwhile, the Mo-W-P/CB hybrid nanoparticles also showed good stability and durability in strong acid electrolyte. Our work provides a route for construction of efficient hybrid electrocatalysts by immobilization of inorganic complexes.

Molybdenum-tungsten Oxide Nanowires Rich in Oxygen Vacancies as An Advanced Electrocatalyst for Hydrogen Evolution.

Electrolysis of water is a promising way to produce hydrogen fuel in large scale. The commercialization of this technology requires highly efficient non-noble metal electrocatalysts to decease the energy input for the hydrogen evolution reaction (HER). In this work, a novel nanowire structured molybdenum-tungsten bimetallic oxide (CTAB-D-W4 MoO3 ) is synthesized by a simple hydrothermal method followed with post annealing treatment. The obtained metal oxides feature with enhanced conductivity, rich oxygen vacancies and customized electronic structure. As such, the composite electrocatalyst exhibits excellent electrocatalytic performance for HER in an acidic environment, achieving a large current density of 100 mA cm-2 at overpotential of only 286 mV and a small Tafel slope of 71.2 mV dec-1 . The excellent electrocatalytic HER performance of CTAB-D-W4 MoO3 is attributed to the unique nanowire structure, rich catalytic active sites and promoted electron transfer rate.

Three‐Dimensional PdCuRu Alloy Porous Nanosheets as Efficient Electrocatalysts for Hydrogen Evolution Reaction in Varied Electrolytes

AbstractNoble metal materials with favorable electronic and geometric structure are considered as outstanding electrocatalysts for hydrogen evolution reaction (HER). However, it is still a grand challenge to increase the specific surface area of the catalyst to expose more active sites from structural advantages and optimize the adsorption/desorption energy of reaction intermediates. Here, we report the design and fabrication of a three‐dimensional (3D) PdCuRu nanostructure that is assembled by porous nanosheets through a facile wet‐chemical and subsequent chemical etching method. Interestingly, the prepared 3D porous nanostructures not only provide a wealth of surface active centers for reactants, but also provide a lot of ways for mass transport and charge transfer. More importantly, the alloy structure effectively optimizes the electronic structures of Ru and Cu, leading them to be favorable for the adsorption/desorption of Hads during HER. As a result, the 3D PdCuRu porous nanosheets (PdCuRu PNSs) display excellent electrocatalytic HER performance in both acidic and alkaline media. It is worth mentioning that the 3D PdCuRu PNSs could also show excellent kinetic stability with negligible activity loss representing a new class a class of promising electrocatalysts for HER.

Ir-Doped Pd Nanosheet Assemblies as Bifunctional Electrocatalysts for Advanced Hydrogen Evolution Reaction and Liquid Fuel Electrocatalysis.

Although great progress in pursuing high-performance catalysts for advanced electrocatalysis has been made, the design of high-efficiency electrocatalysts continues to be a huge challenge for commercializing electrochemical energy technologies. Herein, a three-dimensional (3D) hierarchical assembly nanostructure consisting of ultrathin Ir-doped Pd nanosheets has been well designed, which could serve as a bifunctional electrocatalyst for advanced hydrogen evolution reaction (HER) and liquid fuel electrooxidation. In particular, the optimized Pd83.5Ir16.5 nanocatalyst displays excellent electrocatalytic HER performance with an overpotential of only 73 mV at 10 mA cm-2 along with excellent stability. More importantly, it can also show outstanding electrocatalytic performance for liquid fuel oxidation with a mass activity of 4326.1 mA mgmetal-1 for ethylene glycol oxidation reaction.Mechanistic study reveals that the highly porous 3D nanostructure, the modulation of electronic structure after the introduction of Ir, not only guarantees a high level of exposure of surface active sites and smooth charge transfer but also generates the new active centers for facilitating the adsorption of H2O and recombination of H*, thereby dramatically increasing the intrinsic activity of electrocatalysis.

Stacked Co6W6C nanocrystals anchored on N-doping carbon nanofibers with excellent electrocatalytic performance for HER in wide-range pH

High purity H2 formed by electrochemical water splitting is profound potential green energy. Exploiting advanced electrocatalysts for hydrogen evolution reaction (HER) in both acidic and base environment is of critical significance. Herein, we report a novel hybrid comprising stacked cobalt tungsten carbides nanocrystals on N-doping carbon matrix (Co6W6C–N@CNFs) as a superb HER catalyst over the entire pH range via facile electrospinning and CVD method. On account of its ultrathin size and the strong synergetic interaction between bimetals, coupled with the superior conductivity of N-doping CNFs, Co6W6C–N@CNFs presents superior catalytic properties, with low overpotentials of 86 and 116 mV at η10 and small Tafel slopes of 85 and 101 mV dec−1 in acidic and alkali, respectively, as well as outstanding long-term stability, rivalling its potential to be used intensively in water electrolysis technologies.

Highly dispersive bimetallic sulfides afforded by crystalline polyoxometalate-based coordination polymer precursors for efficient hydrogen evolution reaction

Molybdenum disulfide (MoS2) is viewed as one of the most promising hydrogen evolution reaction (HER) electrocatalyst thanking to its graphene-like layered structure and suitable hydrogen chemisorption free energy. However, its application is still hindered by some obstacles, such as less exposed active sites and poor inherent conductivity. Herein, two new crystalline polyoxometalate-based metal-organic polymers with Co/Ni and Mo, {(C2H2N3)3Co2·6H2O}[H3SiMo12O40]·9H2O (1) and {(C2H2N3)3Ni2·6H2O}[H3SiMo12O40]·5H2O (2) (1,2,4-triazole = C2H2N3) are firstly designed and fabricated, and characterized by sufficient technologies including single-crystal X-ray diffraction and so on. And they are directly utilized as ‘preassembly platform’ reacting with thiourea to synthesize highly dispersive CoS2–MoS2 and Ni3S2–MoS2 bimetallic sulfides with mesoporous structure. In virtue of the synergistic effects, and high dispersiveness and porosity of CoS2/Ni3S2 and MoS2 in carbon cloth (CC), 50%CoS2–MoS2@CC and 50%Ni3S2–MoS2@CC composites display a low overpotential of 222 and 224 mV at 10 mA cm−2, and a small Tafel slope of 64.2 and 65.7 mV·dec−1 in H2SO4 solution, respectively. Such superior electrocatalytic HER performances outperform most of both POM-based and MoS2-based non-noble metal catalysts. Hence, this work presents a facile tactic for engineering highly dispersive bimetallic sulfides with excellent electrocatalytic HER performance.

Bimetallic phosphides embedded in hierarchical P-doped carbon for sodium ion battery and hydrogen evolution reaction applications

Transition metal phosphides have been explored as promising active materials for sodium-ion batteries (SIBs) and hydrogen evolution reaction (HER) applications owing to their unique physical and chemical characteristics. However, they suffer from the drawbacks such as severe agglomeration, and sluggish reaction kinetics. Herein, bimetallic phosphides (Ni2P/ZnP4) embedded in P-doped carbon hierarchical microspheres are demonstrated with robust structural integrity, fast charge transfer, and abundant active sites. As expected, the optimally structured Ni2P/ZnP4 composite exhibits good electrochemical performance as an anode material in SIBs, including high specific capacity, good cycling stability and rate capability. Meanwhile, the Ni2P/ZnP4 composite also exhibits excellent electrocatalytic performance for HER with a small overpotential of 62 mV, a Tafel slope of 53 mV dec−1, as well as excellent stability.

Growth and properties of solvothermally derived highly crystalline Cu2ZnSnS4 nanoparticles for photocatalytic and electrocatalytic applications

This work reports the photocatalytic and electrocatalytic applications of solvothermally derived Cu2ZnSnS4 (CZTS) nanoparticles. The synthesized material was applied for the photocatalytic degradation of Rhodamine B (RhB), a carcinogenic dye. The nanoparticles degrade 83% of RhB in the presence of visible light (589 nm) illumination. A negligible fall in the degradation percentage after 3 photocatalytic cycles and post catalytic properties demonstrate the excellent photostability of the nanostructure. The electrocatalytic performance of CZTS for hydrogen evolution reaction (HER) through water splitting and charge storage reveals their potential applications for efficient electrochemical energy systems. The nanoparticles show excellent electrocatalytic performance for HER as indicated by the low Tafel slope. The Linear Sweep Voltametry (LSV) plot performed after 1000 cyclic voltammetry (CV) cycles shows negligible loss of current confirming the good stability of the nanostructure. Chronoamperometry (CA) performed at constant potential shows negligible loss of current for 12 h, which confirms that the synthesized CZTS is a potential and durable candidate for electrochemical applications. The material is highly stable in both the processes; electrocatalysis as well as photocatalysis.

ZIF-Derived Carbon Nanoarchitecture as a Bifunctional pH-Universal Electrocatalyst for Energy-Efficient Hydrogen Evolution

Development of nonprecious metal-based electrocatalysts supporting hydrogen evolution reaction (HER) in the entire pH range has gained significant importance for harvesting green and renewable energy. Herein, we developed a novel electrocatalyst based on 3D carbon nanoarchitecture hybrid, which consists of CoP nanoparticles (CoP NPs) embedded into N-doped carbon nanotubes (NCNT), grafted on carbon polyhedron (CoP/NCNT-CP) that was prepared by carbonization and low-temperature phosphatization treatment of cobalt-based zeolite imidazole framework (ZIF). Benefiting from the strong synergistic effect and unique 3D structure, the CoP/NCNT-CP hybrid loaded on Ni foam exhibited excellent electrocatalytic HER performance in base with a low overpotential of 165 mV at a current density of 10 mA cm-2, which is competitive with the previously reported Co-based hybrid electrocatalysts. Furthermore, the CoP/NCNT-CP also demonstrated high HER electrocatalytic activities in both neutral and acidic conditions with the overpotentials of 203 and 305 mV at the current density of 10 mA cm-2. Additionally, the bifunctional CoP/NCNT-CP electrode simultaneously acted as an anode for hydrazine oxidation reaction (HzOR) and a cathode for HER. Excellent catalytic performance was demonstrated in base conditions with a low cell potential of 0.89 V at 10 mA cm-2, which was much lower than the voltage of overall water splitting (1.91 V) at the same current density.

Engineering of molybdenum sulfide nanostructures towards efficient electrocatalytic hydrogen evolution

Water splitting is an appealing way of producing hydrogen fuel, which requires efficient and affordable electrode materials to make the overall process viable. In the last couple years, abundant transition metals (and their compounds and hybrids) attracted ever-growing attention as the alternatives of noble metals. Particularly the layered transition metal dichalcogenide (TMDs) are interesting with their stability and promising electrocatalytic performance for hydrogen evolution reaction (HER). However, the neat TMDs are often poor in terms of the abundance of catalytically active sites and electrical conductivity, which limit their application potential significantly. Herein, as a proof-of-concept, we report on the design of a high-performance electrocatalyst system formed by the decoration of ultrasmall molybdenum sulfide (MoS2) nanosheets on carbon nanotubes (CNTs). The ultrasmall MoS2 nanosheets provide distorted lattice, confined size and rich defects, which endows the resulting electrocatalysts (MoS2/CNT) with abundant active sites. The CNTs, on the other hand, serve as the conductive net for ensuring electrocatalytic performance. As a result, the hybrid electrocatalyst exhibits excellent electrocatalytic performance for HER, achieving a large current density of 100 mA cm−2 at overpotential of only 281 mV and a small Tafel slope of 43.6 mV dec−1 along with a decent stability. Our results are of high interest for electrocatalyst technologists as well as hydrogen fuel researchers.

Sub-1.5 nm Ultrathin CoP Nanosheet Aerogel: Efficient Electrocatalyst for Hydrogen Evolution Reaction at All pH Values.

Transition metal phosphides (TMPs) are certified high performance electrocatalysts for the hydrogen evolution reaction (HER). The ultrathin 2D structure of TMPs can offer abundant adsorption sites to boost HER performance. Herein, an ice-templating strategy is developed to prepare CoP aerogels composed of 2D ultrathin CoP nanosheets (<1.5 nm) using sustainable alginate biomass (seaweed extract) as the precursor. The highly porous aerogel structure can not only deliver facile mass transfer, but also prevent aggregation of the nanosheets into layered structures. As expected, the obtained CoP nanosheet aerogels exhibit remarkable stability and excellent electrocatalytic HER performance at all pH values. For instance, the sample CoP-400 presents a low overpotential of 113, 154, and 161 mV versus RHE at a current density of 10 mA cm-2 in 0.5 m H2SO4, 1 m KOH, and 1 m phosphate buffer solution, respectively. In addition, CoP-400 displays low Tafel slopes at all pH values due to the interconnected highly porous structure of the aerogel, indicating that the sample can provide low-resistance channels for mass transport. Density functional theory calculations reveal that P-top and Co bridge on (011) facet of CoP are more favorable sites during the process of HER in acid and alkaline solutions, respectively.

Facile synthesis and excellent electrochemical performance of CoP nanowire on carbon cloth as bifunctional electrode for hydrogen evolution reaction and supercapacitor

In this paper, we report CoP nanowires supported on carbon cloth (CC) (CoP/CC) as a bifunctional electrode for hydrogen evolution reaction (HER) and supercapacitor. CoP/CC possess an excellent electrocatalytic performance for HER, with a Tafel slope of 56 mV/dec and a low overpotential of 68 mV to achieve a current density of 10 mA cm−2 . Remarkably, the bifunctional CoP/CC used as electrode for supercapacitor exhibit a higher specific capacitance of 674 F g−1 at a scan rate of 5 mV s−1 and maintains long-life cycling stability, retaining 86% of the initial capacitance after 10,000 cycles. CoP/CC will be a promising candidate as electrode for HER and supercapacitor.

New insights into high-valence state Mo in molybdenum carbide nanobelts for hydrogen evolution reaction

Hydrogen evolution reaction (HER) is considered to be one of the most promising strategies to create hydrogen. Recently, searching high-efficient, stable, and earth-abundant electrocatalysts to replace precious metals for practical utilizations of HER is attracting more and more attentions. Herein, novel molybdenum carbide nanobelts containing Mo of high-valence state derived from MoO3-ethylenediamine inorganic/organic hybrid precursors are successfully synthesized via a facile one-pot pyrolysis method. The molybdenum carbide nanobelts are characterized using XRD, SEM, TEM and XPS. Moreover, the high-valence state Mo and their relative content in the molybdenum carbide nanobelts can be identified by XPS. The high-resolution XPS spectra of Mo 3d indicates in the molybdenum carbide nanobelts the proportion of high-valence state Mo in active Mo components is 51.3%. More importantly, the as-synthesized products exhibit excellent electrocatalytic activity for HER with a low onset overpotential of 50 mV and a small Tafel slope of 49.6 mV dec−1 in acidic medium (0.5 M H2SO4). Besides, the catalysts require only overpotentials of 143 and 234 mV to achieve current densities of 10 and 220 mA cm−2, respectively. Furthermore, they also exhibit good durability after 2000 cycles and constant current density test. Such excellent electrocatalytic HER performance can be ascribed to the high intrinsic activity of high-valence state Mo in Molybdenum Carbide. Synthesizing molybdenum carbide with high-valence state Mo electrocatalysts for HER will open up an exciting alternative avenue to acquire outstanding HER electrocatalytic activity.