Efficient Electrocatalyst For Hydrogen Evolution Reaction Research Articles

Post-decorated synthesis of metal-organic frameworks derived Ni/Ni3S2@CN electrocatalyst for efficient hydrogen evolution

MOF-derived materials are known as effective electrocatalysts for hydrogen evolution reaction (HER). Herein, a new 2D structured Ni-MOF (CUST-516) was synthesized, and physically post-decorated with glucose, urea and Ni(NO3)2·6H2O simultaneously, used as precursors to obtain Ni/Ni3S2@CN electrocatalyst by high temperature calcination. Ni/Ni3S2@CN shows excellent HER activity with low overpotentials of 141 ​mV and 187 ​mV at 10 ​mA ​cm−2 as well as long-term stability up to 24 ​h in 1.0 ​M KOH and 0.5 ​M ​H2SO4 solutions, respectively. The excellent electrocatalytic performance of Ni/Ni2S3@CN can be attributed to the synergistic effect of multi-components, the unique pore structure derived from precursor MOF, which enables the nanoparticles to be evenly distributed. Moreover, the post-decorated sources help to generate the doping of N elements and carbon layers, which increases the conductivity, prevents the aggregation of nanoparticles and corrosion, resulting in the enhanced complementary properties. This work provides a general post-decorated MOFs derivatization strategy to synthesize low-cost and efficient HER electrocatalysts.

Patchwork-Structured Heterointerface of 1T-WS2/a-WO3 with Sustained Hydrogen Spillover as a Highly Efficient Hydrogen Evolution Reaction Electrocatalyst.

Using tungsten disulfide (WS2) as a hydrogen evolution reaction (HER) electrocatalyst brought on several ways to surpass its intrinsic catalytic activity. This study introduces a nanodomain tungsten oxide (WO3) interface to 1T-WS2, opening a new route for facilitating the transfer of a proton to active sites, thereby enhancing the HER performance. After H2S plasma sulfurization on the W layer to realize nanocrystalline 1T-WS2, subsequent O2 plasma treatment led to the formation of amorphous WO3 (a-WO3), resulting in a patchwork-structured heterointerface of 1T-WS2/a-WO3 (WSO). Addition of a hydrophilic interface (WO3) facilitates the hydrogen spillover effect, which represents the transfer of absorbed protons from a-WO3 to 1T-WS2. Moreover, the faster response of the cathodic current peak (proton insertion) in cyclic voltammetry is confirmed by the higher degree of oxidation. The rationale behind the faster proton insertion is that the introduced a-WO3 works as a proton channel. As a result, WSO-1.2 (the ratio of 1T-WS2 to a-WO3) exhibits a remarkable HER activity in that 1T-WS2 consumes more protons provided by the channel, showing an overpotential of 212 mV at 10 mA/cm2. Density functional theory calculations also show that the WO3 phase gives higher binding energies for initial proton adsorption, while the 1T-WS2 phase shows reduced HER overpotential. This improved catalytic performance demonstrates a novel strategy for water splitting to actively elicit the related reaction via efficient proton transport.

A Tandem Interfaced (Ni3 S2 -MoS2 )@TiO2 Composite Fabricated by Atomic Layer Deposition as Efficient HER Electrocatalyst.

Reported herein is a highly active and durable hydrogen evolution reaction (HER) electrocatalyst, which is constructed following a tandem interface strategy and functional in alkaline and even neutral medium (pH ≈ 7). The ternary composite material, consisting of conductive nickel foam (NF) substrate, Ni3 S2 -MoS2 heterostructure, and TiO2 coating, is synthesized by the hydrothermal method and atomic layer deposition (ALD) technique. Representative results include: (1) versatile characterizations confirm the proposed composite structure and strong electronic interactions among comprised sulfide and oxide species; (2) the material outperforms commercial Pt/C by recording an overpotential of 115mV and a Tafel slope of 67mV dec-1 under neutral conditions. A long-term stability in alkaline electrolytes up to 200 h and impressive overall water splitting behavior (1.56V @ 10mA cm-2 ) are documented; (3) implementation of ALD oxide tandem layer is crucial to realize the design concept with superior HER performance by modulating a variety of heterointerface and intermediates electronic structure.

Engineering Phase Stability of Semimetallic MoS2 Monolayers for Sustainable Electrocatalytic Hydrogen Production.

1T'-phase MoS2 possesses excellent electrocatalytic performance, but due to the instability of the thermodynamic metastable phase, its actual electrocatalytic effect is seriously limited. Here, we report a wet-chemical synthesis strategy for constructing rGO/1T'-MoS2/CeO2 heterostructures to improve the phase stability of metastable 1T' phase MoS2 monolayers. Importantly, the rGO/1T'-MoS2/CeO2 heterostructure exhibits excellent electrocatalytic hydrogen evolution reaction (HER) performance, which is much better than the 1T'-MoS2 monolayers. The synergistic effects between CeO2 nanoparticles (NPs) and 1T'-MoS2 monolayers were systematically investigated. 1T'-MoS2 monolayers combined with the cocatalyst of CeO2 NPs can produce lattice strain and distortion on 1T'-MoS2 monolayers, which can tune the energy band structure, charge transfer, and energy barriers of hydrogen atom adsorption (ΔEH), leading to promotion of the phase activity and stability of 1T'-MoS2 monolayers for hydrogen production. Our work offers a feasible method for the preparation of efficient HER electrocatalysts based on the engineering phase stability of metastable materials.

Modulation of the B4N monolayer as an efficient electrocatalyst for hydrogen evolution reaction

Exploring stable catalysts with an efficient hydrogen evolution reaction (HER) arises intense concerns due to its renewable and low-cost properties. In this work, we have systematically investigated a two-dimensional (2D) material, namely, B 4 N monolayer as efficient HER electrocatalysts based on first-principles computations. When the material is metal-free, the calculated Gibbs free energy (ΔG H∗ ) corresponding to hydrogen coverages of 2/4 reaches to 0.005 eV, which is better than that of the Pt catalyst. Moreover, we also find that the HER activity of the B 4 N monolayer is sensitive to the strains-driven. The single metal atom supported on B 4 N can still make the value of ΔG H∗ close to 0 eV for Cr/B 4 N and V/B 4 N. These results reveal that the B 4 N monolayer is a promising candidate for HER applications. • The B 4 N monolayer is a promising candidate for HER applications. • Hydrogen coverage and external strain engineering can improve HER activity. • The HER performance can be enhanced with doping of single transition metal (TM) atom.

Defect-rich engineering of Ni-incorporated tungsten oxides micro-flowers on carbon cloth: A binder-free electrode for highly efficient hydrogen evolution reaction

Hydrogen generated by electrocatalysis water splitting is a promising way to harvest clean energy. However, exploring the cheap and highly efficient electrocatalysts with Pt-like activity for hydrogen evolution reaction (HER) remains great challenges. Herein, we report hierarchical Ni-incorporated oxygen vacancies-rich tungsten oxides micro-flowers on 3D conductive carbon cloth support (denoted as Ni–W H2-550) as a binder-free electrode for high efficient hydrogen evolution. The binder-free 3D structure and the synergistic effect between Ni-incorporated and rich oxygen vacancies can regulate the electronic structure, facilitate the electron transfer, and enlarge the exposed active sites. The as-prepared Ni–W H2-550 exhibits a low overpotential of 25 mV at 10 mA cm−2 with robust stability in alkaline electrolyte solution over 20 h. This study opens up a concise strategy toward the preparation of the low-cost and highly efficient electrocatalyst for HER.

The In‐situ Growth of Ru Modified CoP Nanoflakes on Carbon Clothes as Efficient Electrocatalysts for HER**

AbstractExploring highly efficient, durable and low‐cost catalysts for hydrogen evolution reaction (HER) is crucial to promoting the development of electrochemical water splitting systems but remains challenging. In this work, the Ru‐modified CoP nanoflakes on carbon clothes (Ru‐CoP/CC) are fabricated via an in‐situ hydrothermal method, followed by low‐temperature phosphatized treatments. According to X‐ray photoelectron spectroscopy (XPS) measurements, the Ru doping induces the electron deviation from Ru to Co−P, and makes Co ions be an electron‐rich state. It is revealed that the introduction of Ru can effectually reconstruct the electron coordination environment of Co−P. The resultant Ru‐CoP/CC catalyst shows outstanding HER performance with an ultralow overpotential of 45 mV at 10 mA cm−2. Moreover, the obtained catalyst exhibits long‐term durability at 20 mA cm−2 for 20 h in the alkaline solution. This work opens a new avenue to lower the usage of noble metal in electrocatalyst and helps to developing a high‐performance electrocatalyst for HER.

Dry and hydrated defective molybdenum Disulfide/Graphene bilayer heterojunction under strain for hydrogen evolution from water Splitting: A First-principle study

In search of exploiting cost-effective, highly stable, efficient, and greatly active electrocatalysts for hydrogen evolution reaction (HER), molybdenum disulfide-graphene heterostructures (MoS2/graphene) are promising, in contrast to noble metals. We used density functional theory (DFT) to examine the changes in the electronic structure of MoS2/graphene under compressive strain for structural defects in the MoS2 and graphene layers, as well as from hydration of the MoS2 layer. In the pristine MoS2/graphene heterostructure, a small bandgap (minigap) is opened at the graphene Dirac point, which is located above the Fermi energy, for dry and hydrated configurations. The presence of sulfur and carbon vacancies in the MoS2/graphene upshifts the Dirac point and widens the minigap. However, additional sulfur vacancies further widen or shrink the minigap depending on the location of the MoS2 conduction band bottom and the presence of defect bands at the Dirac point. The minigap tunability in the MoS2/graphene heterostructure could be engineered for producing efficient HER electrocatalysts and beyond. The Quantum Theory of Atoms in Molecules (QTAIM) reveals SC bond critical points, which correspond to van der Waals forces interactions in agreement with the Non-covalent Interaction (NCI) analysis. A correlation is drawn between the minigap and the electron density at the SC bond critical points.

Conducting scaffold supported defect rich 3D rGO-CNT/MoS2 nanostructure for efficient HER electrocatalyst at variable pH

Designing a suitable noble metal-free electrocatalyst for the hydrogen evolution reaction (HER) is enduring challenge. Molybdenum disulfide (MoS 2 ) shows structural and electronic advantages as potential HER electrocatalyst. The structural and electronic design of MoS 2 electrocatalysts should be considered to improve the efficiency and stability of MoS 2 based electrodes. This report shows that the presence of synergistic interaction significantly improves the HER electrocatalytic activity of defect-rich 3D rGO-CNT/MoS 2 composites. The Defect-rich conductive scaffold supported nanostructures can improve the catalytic performance and stability. Lowering of the HOMO-LUMO gap supervises the charge transfer resistance of the nanostructure . The turnover frequency value indicates that 3D rGO-CNT/MoS 2 acts as the potential electrocatalyst and the overpotential observed at a current density of 10 mA cm −2 in acidic and alkaline media are 88 mV and 172 mV, respectively. This investigation provides a new idea to develop molybdenum disulfide and scaffolds based 3D nanostructures to improve the inherent electrocatalytic activity of HER. • Synthesis of conducting scaffold supported 3D rGO-CNT/MoS 2 nanostructure. • Physicochemical analysis leads to defect rich nanostructure with different S/Mo ratio. • Formation of conducting scaffold based nanocomposite enhance HER activity. • 3D nanostructure provide extra operational stability in acidic and alkaline pH.

Oleylamine-Mediated Synthesis of Ultrasmall Α-Moc1-X Nanoparticles and Rgo/Α-Moc1-X Nanocomposite as Efficient Hydrogen Evolution Reaction Electrocatalyst in Acidic Medium

Oleylamine-Mediated Synthesis of Ultrasmall Α-Moc1-X Nanoparticles and Rgo/Α-Moc1-X Nanocomposite as Efficient Hydrogen Evolution Reaction Electrocatalyst in Acidic Medium

Amorphous Ru nanoclusters onto Co-doped 1D carbon nanocages enables efficient hydrogen evolution catalysis

The development of high-performance electrocatalysts for hydrogen evolution reaction (HER) is of great significance for green, sustainable, and renewable energy conversion. Herein, we report the synthesis of amorphous Ru clusters on Co-doped defect -rich hollow carbon nanocage (a-Ru@Co-DHC) as an efficient electrocatalyst for HER in the basic media. Due to the advantages such as high surface area, rich edge defect, atomic Co doping and amorphous Ru clusters, the as-made a-Ru@Co-DHC displays an efficient HER performance with a near-zero onset overpotential, a low Tafel slope (62 mV dec −1 ), a low overpotential of 40 mV at 10 mA cm −2 and high stability, outperforming the commercial Ru nanocrystal/C, commercial Pt/C, and other reported Ru-based catalysts. This work provides a new insight into designing new metal doped carbon nanocages catalysts supported by amorphous nanoclusters for achieving the enhanced electrocatalysis. A novel kind of amorphous Ru clusters@Co-doped defect-rich hollow carbon nanocage (a-Ru@Co-DHC) catalyst has been developed for efficient electrocatalysis of hydrogen evolution reaction in basic media due to synergistic effect of edge defect, atomic Co doping and dispersed amorphous Ru clusters.

Construction of an N-Decorated Carbon-Encapsulated W2C/WP Heterostructure as an Efficient Electrocatalyst for Hydrogen Evolution in Both Alkaline and Acidic Media.

Tungsten carbide (W2C) has emerged as a potential alternative to noble-metal catalysts toward hydrogen evolution reaction (HER) owing to its Pt-like electronic configuration. However, unsatisfactory activity, dilatory electron transfer, and inefficient synthesizing methods, especially for nanoscale particles, have severely hindered its large-scale applications. Herein, a novel heterostructure composed of W2C and tungsten phosphide (WP) embedded in nitrogen-decorated carbon (W2C/WP@NC) was constructed as an efficient HER electrocatalyst. The as-prepared W2C/WP@NC catalyst exhibits remarkable electrocatalytic activity and robust durability toward HER both in acids and bases. More notably, the W2C/WP@NC catalyst demonstrates low overpotentials of 116.37 and 196.2 mV to afford a current density of 10 mA cm-2 and reveals slight potential decays of about 6.4 and 7.64% over 12 h continuous operation in bases and acids, respectively. The overall water-splitting performance was further evaluated using the W2C/WP@NC catalyst as the cathode and commercial RuO2 as the anode in an electrolyzer, which can realize an overall current density of 10 mA cm-2 and maintain long durability of more than 12 h with a small cell voltage of 1.723 V. This work opens up new opportunities for exploring cost-efficient electrocatalysts in sustainable energy conversion.

Biomass‐based transition metal phosphides supported on carbon matrix as efficient and stable electrocatalyst for hydrogen evolution reaction

An effective and eco-friendly catalyst for hydrogen evolution reaction (HER) shows significance for new clean energy technologies. The TMPs are generally regarded as efficient electrocatalysts for HER. Unfortunately, the synthetic procedures of TMPs usually suffered from high cost, complexity, and toxicity caused by the use of chemical phosphorus sources. Phosphorus and nitrogen pollution lead to water eutrophication and consequent algae blooms. We use a kind of algae (caused by eutrophication) to develop TMP nanoparticles supported on the porous carbon matrix for HER by a one-step calcination treatment, the preparation method is sustainable, economical, and effective. For the optimal catalyst Co2P nanoparticles supported on chlorella-derived porous N-doped carbon matrix (Co2P-C-NPC), the HER overpotential is measured to be 151 mV (acid condition) and 252 mV (alkaline condition) at the current density of 10 mA cm−2. The excellent HER performance results from the uniform dispersity, high content of carbon, phosphorus and nitrogen in the algae, the algae's high surface and porosity. If adverse element-rich biomass can be converted into a useful catalyst material, then the efficient and eco-friendly for water splitting is possible.

Compressive Strain in N-Doped Palladium/Amorphous-Cobalt (II) Interface Facilitates Alkaline Hydrogen Evolution.

The development of palladium-based catalysts for alkaline hydrogen evolution reaction (HER) is highly desired for renewable hydrogen energy systems, yet still challenging due to the strong palladium-hydrogen bond. Herein, the bottleneck is largely overcome by constructing a nitridation-induced compressively strained-interface N-doped palladium/amorphous cobalt (II) interface (N-Pd/A-Co(II)), which dramatically boosts HER performance in alkaline condition. The optimized catalyst with the compressive strain of 2.7% exhibits the higher activity with an overpotential of only 58 mV to achieve the current density of 10 mA cm-2 , much better than those of pure Pd (327 mV), and the state-of-art Pt/C (78 mV). Notably, it also shows excellent stability with negligible decline during a 30 h stability test. Detailed analyses reveal that the strong absorption of Hads on Pd can be efficiently reduced via the compressively strained N-doped Pd. And the amorphous Co(II) component accelerates the water dissociation. Consequently, the cooperative effect between the compressed N-doped Pd and amorphous Co(II) creates the impressive HER performance in alkaline condition, highlighting the importance of the functional interface to develop efficient electrocatalysts for HER and beyond.

Dual-phase MoC-Mo2C nanosheets prepared by molten salt electrochemical conversion of CO2 as excellent electrocatalysts for the hydrogen evolution reaction

Dual-phase structures usually have better electrocatalytic activity in the hydrogen evolution reaction (HER) due to synergistic effects. Herein, a novel strategy is proposed to prepare dual-phase MoC-Mo2C nanosheets by electro-reduction of CO2 on the Mo cathode in CaCl2-CaO molten salts through an in situ reaction between molybdenum and carbon. The composition of the molybdenum carbide samples can be adjusted by the cell voltage and temperature. As the Mo2C contents go up, the HER activity of molybdenum carbide increases initially and then decreases slightly. The dual-phase MoC-Mo2C nanosheets prepared at 850 °C and 2.5 V show the best activity due to the hydrogen adsorption-desorption balance. The results reveal an innovative and sustainable strategy to prepare highly efficient HER electrocatalysts and also a green route to recycle and utilize CO2.

Novel Ni2P-microporous nickel phosphite supported on nitrogen-doped graphene composite electrocatalyst for efficient hydrogen evolution reaction

Transition metal phosphides are regarded as promising hydrogen evolution reaction (HER) electrocatalysts for water splitting. An efficient mass-transfer mechanism can be promoted through constructing microporous structures. In addition, introducing carbon materials as carriers to form interface interactions is beneficial for increasing electronic conductivity so as to promote the catalytic activity further. In this work, a nitrogen-doped graphene (NGO)-supported microporous nickel phosphide-nickel phosphite (Ni2P-Ni11(HPO3)8(OH)6@NGO, Ni2P-MPH@NGO), where Ni2P nanoparticles uniformly fill the micropores of Ni11(HPO3)8(OH)6 and then are supported on two-dimensional NGO via a simple two-step method, has been studied as a novel efficient electrocatalyst for HER. Compared with carbon nanotubes and graphene as carbon-based carriers, the optimized Ni2P-MPH@NGO catalyst shows excellent HER performance with a smaller overpotential, lower Tafel slope and long-term catalytic durability under acid conditions. The results demonstrate that NGO can enhance the catalytic activity of Ni2P-MPH@NGO efficiently. The results show that the synergistic effect of the microporous structure of Ni11(HPO3)8(OH)6 and NGO effectively improves the catalytic activity of the Ni2P-MPH@NGO composite catalyst, which provides a promising strategy for the design of a new low-cost and high-efficiency HER electrocatalysts.

Dual-phase amorphous-nanocrystalline nanoporous sites activated in Mo inserted CuTi metallic glass as efficient electrocatalysts for hydrogen evolution reaction

The production of noble metal-free, high-performance, earth-abundant hydrogen evolution reaction (HER) electrocatalysts is a challenging search but indispensably a vital issue for green energy conversion and production. Herein, we report a nanoporous self-supported CuTiMo site nanostructured from Cu60Ti37Mo3 metallic glass as a highly efficient electrocatalyst for HER. The development of nanoporous structure from metallic glassy alloy rather than the conventional crystalline alloy is carried out, and a comprehensive plausible working mechanism of nanoporous structure development is outlined. The novelty of the present research is the nanostructuring of metallic glasses to form crystalline and amorphous dual sites. The dual phased nanoporous electrocatalyst exhibits high catalytic activity comparable to standard Pt-catalyst at higher current densities (>60 mA cm−2). The electrocatalyst is stable even at high current densities (>100 mA cm−2) and needs much lesser overpotential than that of standard Pt/C catalyst for HER reaction at high current densities. The dealloying of defect-free metallic glasses leads to the formation of a large number of catalytic active sites, and the introduction of Mo into the CuTi matrix leads to accelerated H2 adsorption/desorption kinetics. The dealloyed metallic glass requires an overpotential of 220 mV vs. RHE to attain a current density of 100 mA cm−2 in an alkaline HER reaction. Based on the advantages of nanoporous structure development from highly metastable metallic glasses, the high active surface area of nanoporous structure on a high conductive substrate, the exceptional stability for long term and at high current densities, the proposed nanoporous metallic glass composite electrode is of significance for a diversity of applications for green energy production.

Fe-doped MoS2 nanosheets array for high-current-density seawater electrolysis

Designing highly active and cost-effective electrocatalysts for seawater-splitting with large current densities is compelling for developing hydrogen energy. Great advancements in hydrogen evolution reaction (HER) have been achieved, but the progress on driving HER in seawater is still limited. Herein, Fe-doped MoS2 nanoshseets array supported by 3D carbon fibers was explored to be an efficient HER electrocatalyst operating in seawater. Strikingly, it exhibited small overpotentials of 119 and 300 mV to reach the current densities of 10 and 250 mA cm–2 in buffered seawater, respectively, both of them are comparable to the best-reported values under similar conditions. Meantime, the catalyst could keep the stable HER activity for 30 h without notable loss. Theoretical calculations revealed that Fe doping increases the S-edge activity. Our work provides a new avenue for designing MoS2-based HER electrocatalysts for industry application.

Atomically dispersed low-cost transition metals catalyze efficient hydrogen evolution on two-dimensional SnO nanosheets

Two-dimensional (2D) electrocatalyst plays an important role in hydrogen production via water splitting. In this work, the first-principles calculation was used to investigate the hydrogen evolution reaction (HER) performance of transition metal (TM) single atom catalysts (SACs) on 2D SnO nanosheets. Among the TM considered (TM = V, Cr, Mn, Fe, Co, Ni, Cu and Pt), V, Fe, Co, Ni, Cu and Pt can effectively improve the catalytic activity of SnO. More importantly, the low-cost Co can exhibit promising HER performance with the Gibbs free energy as low as ~0.015 eV, which is competitive with the precious catalyst Pt. The theoretical exchange current densities of Co SACs can reach ~10−16 A/site. The exciting HER activity is mainly facilitated through the d-d hybridization between the TM and Sn atoms on the SnO surface, which introduces new electron states near the Fermi level. Our work highlights the complexity and diversity of the effect of TM SACs on SnO nanosheets and implies their potential applications as efficient HER electrocatalysts.

Single atom Ru doping 2H-MoS2 as highly efficient hydrogen evolution reaction electrocatalyst in a wide pH range

It’s a huge challenge to develop a hydrogen evolution reaction (HER) catalyst with a wide pH range. Herein, single atom ruthenium-doped molybdenum disulfide with high 2H phase content (Ru@2H-MoS2) catalysts are synthesized by a two-step hydrothermal method, they are named as Ru0.05@2H-MoS2, Ru0.10@2H-MoS2 and Ru0.12@2H-MoS2 based on the amount of Ru (mmol) added to 2H-MoS2. The results indicate that single atom Ru substituting for molybdenum atom leads to more active centers and some vacancies, thus improving the property of 2H-MoS2 for HER. Among them, Ru0.10@2H-MoS2 shows the lowest HER overpotentials of 137, 51 and 168 mV at 10 mA cm-2 in 1.0 M PBS, 1.0 M KOH and 0.5 M H2SO4, respectively. The density functional theory (DFT) further indicates that the Ru@2H-MoS2 has a lower Gibbs free energy of H-adsorption (ΔGH*). Therefore, this study offers an effective way to reasonably design and synthesize efficient MoS2-based catalysts in a wide pH range.