Electrocatalytic Activity For Hydrogen Evolution Research Articles

High-density low-coordination Ni single atoms anchored on Ni-embedded nanoporous carbon nanotubes for boosted alkaline hydrogen evolution.

Modulating the coordination environment of single-atom catalysts is considered an effective way to boost the electrocatalytic activity of the hydrogen evolution reaction. Herein, a novel electrocatalyst comprising high-density low-coordination Ni single atoms anchored on Ni-embedded nanoporous carbon nanotubes (Ni-N-C/Ni@CNT-H) is constructed through a self-template assisted synthetic strategy. We demonstrate that the in situ generated AlN nanoparticles not only serve as the template for the formation of the nanoporous structure, but also contribute to the coordination between Ni and N atoms. Benefiting from the optimized charge distribution and hydrogen adsorption free energy of the unsaturated Ni-N2 active structure and nanoporous structure of the carbon nanotube substrate, the resultant Ni-N-C/Ni@CNT-H exhibited outstanding electrocatalytic hydrogen evolution activity with a low overpotential of 175 mV at a current density of 10 mA cm-2, and a long-term durability for over 160 h in continuous operation. This work provides a new insight and approach to the design and synthesis of efficient single-atom electrocatalysts toward hydrogen fuel production.

Constructing double-shell structured N-C-in-Co/N-C electrocatalysts with nanorod- and rhombic dodecahedron-shaped hollow morphologies to boost electrocatalytic activity for hydrogen evolution and triiodide reduction reaction

With the increasing energy demands and impending climate change, significant concerns have been raised over the metal–organic frameworks (MOFs)-derived porous carbons and their utilization for hydrogen evolution reaction (HER) and triiodide reduction reaction (IRR). However, the provision of high intrinsic activity, active-site accessibility, and structural stability of MOF-derived Co-embedded N-doped carbon (Co/N-C) for HER and IRR is challenging. In this work, core-shell MOF-in-MOF precursors are designed to construct novel double-shell N-C-in-Co/N-C electrocatalysts with nanorod- and rhombic dodecahedron-shaped hollow morphologies (NR-H-C and RD-H-C). The double-shell structured NR-H-C and RD-H-C significantly enhance the HER and IRR activity of Co-MOF-derived Co/N-C. Specifically, NR-H-C achieves a high N-content (10.35 at.%), large specific surface area (590.87 m2 g−1), and hierarchical porous configuration (micropores and mesopores). When NR-H-C is applied as the HER catalyst in alkaline electrolyte, it exhibits an admired overpotential of 123 mV at 10 mA cm−2 and a Tafel slope of 51 mV dec−1. The solar cell adopting NR-H-C as counter electrode for IRR achieves a high short circuit current density of 16.77 mA cm−2, an open-circuit voltage of 0.745 V, a fill factor of 0.682, and a power conversion efficiency of 8.51%, higher than that of Pt-based solar cell (16.26 mA cm−2, 0.744 V, 0.602, and 7.28%). The elucidatory Volmer-Heyrovsky HER mechanism and reversed Volmer-Heyrovsky IRR mechanism give a better understanding of the enhanced dual-functional activity of NR-H-C. This work provides an essential information for the rational design of high-performance dual-functional HER and IRR catalysts and further open up a new avenue for the construction of multicomponent MOFs in the energy conversion field.

Ordered Mesoporous Intermetallic PtP 2 Nanoparticles with Enhanced Electrocatalytic Activity and Stability for Hydrogen Evolution

Ordered Mesoporous Intermetallic PtP ₂ Nanoparticles with Enhanced Electrocatalytic Activity and Stability for Hydrogen Evolution

Vanadium Carbide Film Formed through Molten Salt Electrolysis of Sodium Metavanadate for Efficient Electrocatalytic Hydrogen Evolution

The utilization of non-precious electrocatalysts is key-enabling to mitigate challenges in energy and environmental sustainability. Herein, we report a vanadium carbide (VC) film generated from molten salt electrolysis of sodium metavanadate (NaVO3) on carbon cloth cathode. The VC forms on carbon cloth by spontaneous thermal nucleation and electrochemical growth. The molten salt electrolysis enhances the adhesion and electronic interaction of VC films with carbon cloth, resulting in an electrocatalytic activity for hydrogen evolution with a low overpotential (97 mV) at 10 mA cm−2 and long-lasting stability (50 h) in acidic media. This work provides a molten salt electrolysis integrating preparation of electrocatalysts and value-added utilization of vanadium slag.

Engineering multifunctional carbon black interface over Mn0.5Cd0.5S nanoparticles/CuS nanotubes heterojunction for boosting photocatalytic hydrogen generation activity

Developing exceptionally robust and cost-effective cocatalysts to suppress charge recombination and reduce the reaction energy barrier remains an enormous challenge for producing high-valued and storable hydrogen fuel from photocatalytic water splitting. Herein, novel Mn0.5Cd0.5S nanoparticles modified with multifunctional carbon black (CB) nanowires and CuS nanotubes as dual cocatalysts were fabricated via sonochemical loading, and subsequent in-situ deposition routes. In this ternary hierarchical architecture, both CB nanowires and CuS nanotubes can serve as normal electron cocatalysts to markedly promote the hydrogen generation performance by lowering the thermodynamic overpotential for hydrogen evolution. Moreover, due to the high electrical conductivity, the multifunctional CB material can also function as a bridge to effectively capture and transmit the photoexcited electrons from Mn0.5Cd0.5S to CuS with outstanding electrocatalytic hydrogen evolution activity, thus maximizing the carrier separation and H2-evolution reaction kinetics. Interestingly, the cooperative effects between CB and CuS dual cocatalysts are also helpful for improving the oxidation capacity of photoexcited holes by lowering the valence band position of Mn0.5Cd0.5S, which further accelerates the electron-hole separation. As a result, the constructed Mn0.5Cd0.5S/CB/CuS hierarchical multiheterojunction catalyst shows the superior hydrogen generation efficiency of 819.9 μmol h−1 and excellent stability under simulated solar light irradiation.

Efficient Charge Transfer in Z‐Scheme g‐C3N4/Cu/MoS2 Heterojunctions for Enhanced Photocatalysis and Photoenhanced Electrocatalysis

AbstractEfficient charge separation and transfer is always an important prerequisite for efficient photocatalysis. Herein, g‐C3N4/Cu/MoS2 Z‐scheme heterojunctions are successfully constructed by a two‐step calcination method, in which Cu nanoparticles are embedded as an electronic conductor between g‐C3N4 and MoS2. g‐C3N4/Cu/MoS2 composites reveal excellent photocatalytic activity. The rate of hydrogen production reaches to 970.5 µmol g−1 h−1, which is 22 and 2.63 times of that of g‐C3N4 and g‐C3N4/MoS2, respectively. Meanwhile, due to the significant enhancement of the conductivity of g‐C3N4/Cu/MoS2 and the efficient charge transfer, its electrocatalytic hydrogen evolution activity is also far superior. In addition, the electrocatalytic activity of g‐C3N4/Cu/MoS2 under light irradiation is significantly improved compared with that under dark condition. This is ascribed to the decrease of charge transfer resistance in the Z‐scheme system during light irradiation. The photochemical and electrochemical properties of g‐C3N4/Cu/MoS2 composites are compared with those of g‐C3N4/MoS2, which illustrate that the construction of g‐C3N4/Cu/MoS2 Z‐scheme heterojunction is an important factor to increase the charge transfer rate. The result provides a new idea for the realization of efficient charge transfer and the synergistic catalytic of photo and electro for water decomposition.

Silk fibroin derived porous carbon aerogels confined hyperdispersed Rh nanoparticles to achieve electrocatalytic hydrogen evolution under high current density

In order to meet the current demand for clean energy and realize industrial application, it is urgent to develop highly efficient catalysts for hydrogen production from electrolytic water. Herein, we successfully synthesize hyperdispersed Rh nanoparticles on silk fibroin derived porous N-doped carbon aerogels (N-Rh/CA) using environment friendly silk fibroin as precursor material. The bonding between Rh and N anchored Rh nanoparticles uniformly super-dispersed on the substrate, exposing plentiful active sites. This N-Rh/CA with ultra-low metal content (2 wt %) exhibits the Pt-like electrocatalytic activity for hydrogen evolution, delivering current density of 10 and 100 mA cm−2 at a ultrasmall overpotential of 65 mV and 210 mV, respectively. Meanwhile, N-Rh/CA possesses a mass activity of 196.81 A g−1 at potential of 150 mV, and exhibits outstanding economic efficiency compared with Pt/C and reported Rh-based electrocatalyst. Furthermore, the electrocatalyst showed superior stability for the hydrogen evolution reaction, paving way for its potential industrial application.

Modulating the electronic structure of Mo species by forming Cr2O3/MoN interface for boosted electrocatalytic HER performance

• Cr 2 O 3 /MoN interface nanosheet electrocatalyst is facilely designed and synthesized. • The electronic structure of Mo atom is optimized by creating Cr 2 O 3 /MoN interface. • The constructed Cr 2 O 3 /MoN exhibits a promising HER activity alkaline environment. Hydrogen production from water splitting in alkaline solution has been hampered by the cleavage of strong OH-H bond with high energy barrier. Herein, we develop the Cr 2 O 3 /MoN interface nanosheets for hydrogen evolution in basic media. The creation of the interface between Cr 2 O 3 and MoN crystal effectively tunes the electronic structure of Mo atom, making it easier to accelerate the dissociation of water molecule. Consequently, the Cr 2 O 3 /MoN interface electrocatalyst delivers the current density of 10 mA cm −2 at the overpotential of 30 mV and the Tafel slope is 61.3 mV dec -1 together with robust durability, providing an efficient avenue to improve electrocatalytic hydrogen evolution activity in basic solution.

Ultrafine molybdenum silicide nanoparticles as efficient hydrogen evolution electrocatalyst in acidic medium

Molybdenum silicides are promising electrocatalysts for hydrogen evolution in acidic environment due to their dual characteristics of metal and ceramics as well as high electrical conductivity and acid resistance. At present, most of the transition metal silicides were synthesized at high temperature, resulting in large particle size and small specific surface area, which seriously limits their electrocatalytic applications. Herein, we report a low temperature strategy for the synthesis of ultrafine Mo5Si3 and MoSi2 nanoparticles with diameter of ∼5 nm by molten salt method. Results show that both of them demonstrated excellent electrocatalytic hydrogen evolution activity and stability in 0.5 M H2SO4 solution, in which the overpotentials of Mo5Si3 and MoSi2 nanoparticles at 10 mA cm−2 are 80 mV and 94 mV, respectively. This general strategy may light up the preparation of ultrafine transition metal silicides nanoparticles and facilitate their applications in electrocatalytic areas.

In-plane strain engineering in ultrathin noble metal nanosheets boosts the intrinsic electrocatalytic hydrogen evolution activity

Strain has been shown to modulate the electronic structure of noble metal nanomaterials and alter their catalytic performances. Since strain is spatially dependent, it is challenging to expose the active strained interfaces by structural engineering with atomic precision. Herein, we report a facile method to manipulate the planar strain in ultrathin noble metal nanosheets by constructing amorphous–crystalline phase boundaries that can expose the active strained interfaces. Geometric-phase analysis and electron diffraction profile demonstrate the in-plane amorphous–crystalline boundaries can induce about 4% surface tensile strain in the nanosheets. The strained Ir nanosheets display substantially enhanced intrinsic activity toward the hydrogen evolution reaction electrocatalysis with a turnover frequency value 4.5-fold higher than the benchmark Pt/C catalyst. Density functional theory calculations verify that the tensile strain optimizes the d-band states and hydrogen adsorption properties of the strained Ir nanosheets to improve catalysis. Furthermore, the in-plane strain engineering method is demonstrated to be a general approach to boost the hydrogen evolution performance of Ru and Rh nanosheets.

Hydrothermal synthesis of Ni(II) or Co(II)-based MOF for electrocatalytic hydrogen evolution

Electrocatalytic hydrogen evolution reactions (HER) can produce clean hydrogen energy. Precious metal electrocatalysts had excellent electrocatalytic activity. However, its limited resources and high price limited its large-scale application. Therefore, the design of efficient, stable and low-cost non-precious metal electrocatalysts has become the key to improving HER efficiency. Herein, we synthesized two cobalt and nickel-based Metal-Organic Frameworks (MOFs), [Ni(bib)2(SO4)]n (Ni-MOF) and [Co(bib)2(SO4)]n (Co-MOF) using bib as a ligand (bib = 1,4-bis(1-imidazolyl)benzene). Ni-MOF-T or Co-MOF-T was obtained by high-temperature calcination under the nitrogen atmosphere. Ni-MOF-800 or Co-MOF-800 exhibited high electrocatalytic hydrogen evolution activity. Besides, the electrocatalytic performance of Co-MOF@Zn-800 obtained by doping zinc ions in Co-MOF was improved.

Symmetry-Breaking-Induced Multifunctionalities of Two-Dimensional Chromium-Based Materials for Nanoelectronics and Clean Energy Conversion

Structural symmetry breaking, which could lead to exotic physical properties, plays a crucial role in determining the functions of a system, especially for two-dimensional (2D) materials. Here, we demonstrate that multiple functionalities of 2D chromium-based materials can be achieved by breaking inversion symmetry via replacing $Y$ atoms in one face of pristine $\mathrm{Cr}$Y (Y = $\mathrm{P}$, $\mathrm{As}$, $\mathrm{Sb}$) monolayers with $\mathrm{N}$ atoms, i.e., forming Janus ${\mathrm{Cr}}_{2}\mathrm{N}Y$ monolayers. The functionalities include gapless spin, very low work function, inducing carrier doping, and catalytic activity, which are predominately ascribed to the large intrinsic dipole of Janus ${\mathrm{Cr}}_{2}\mathrm{N}Y$ monolayers, giving them great potential for various applications. Specifically, ${\mathrm{Cr}}_{2}\mathrm{NSb}$ is found to be a spin-gapless semiconductor, ${\mathrm{Cr}}_{2}\mathrm{NP}$ and ${\mathrm{Cr}}_{2}\mathrm{NHPF}$ can simultaneously induce n- and p-type carrier doping for two graphene sheets with different concentrations (forming an intrinsic p-n vertical junction), and ${\mathrm{Cr}}_{2}\mathrm{N}Y$ exhibits excellent electrocatalytic hydrogen-evolution activity, even superior to that of benchmark $\mathrm{Pt}$. The results confirm that breaking symmetry is a promising approach for the rational design of multifunctional 2D materials.

Synthesis of metal (Ga, Co and Fe) 5,15-bis(pentafluorophenyl)-10-ethoxycarbonylcorrole and their electrocatalytic hydrogen evolution activity

5,15-bis(pentalfluorophenyl)-10-ethoxycarbonylcorrole and their metal complexes (metal = Ga, Co, Fe) had been synthesized and characterized (new complexes). These metal complexes had been used as electrocatalysts for hydrogen evolution reaction (HER) in organic acid and aqueous medium, in which the gallium corrole was firstly used for HER. The results showed that the redox potential of central metal atom for metal-centered metal (eg. Co and Fe) corroles plays a significant role in adjusting catalytic HER activity. Gallium corrole is a ligand-centered HER catalyst, the electronic structure of corrole ligand may play a key role in controlling the electrocatalytic activity.

General Synergistic Capture-Bonding Superassembly of Atomically Dispersed Catalysts on Micropore-Vacancy Frameworks.

Atomically dispersed catalysts are a new type of material in the field of catalysis science, yet their large-scale synthesis under mild conditions remains challenging. Here, a general synergistic capture-bonding superassembly strategy to obtain atomically dispersed Pt (Ru, Au, Pd, Ir, and Rh)-based catalysts on micropore-vacancy frameworks at a mild temperature of 60 °C is reported. The precise capture via narrow pores and the stable bonding of vacancies not only simplify the synthesis process of atomically dispersed catalysts but also realize their large-scale preparation at mild temperature. The prepared atomically dispersed Pt-based catalyst possesses a promising electrocatalytic activity for hydrogen evolution, showing an activity (at overpotential of 50 mV) about 21.4 and 20.8 times higher than that of commercial Pt/C catalyst in 1.0 M KOH and 0.5 M H2SO4, respectively. Besides, the extremely long operational stability of more than 100 h provides more potential for its practical application.

Back Cover: Introducing Water‐Network‐Assisted Proton Transfer for Boosted Electrocatalytic Hydrogen Evolution with Cobalt Corrole (Angew. Chem. Int. Ed. 9/2022)

A cobalt corrole with an appended crown ether unit displays significantly boosted electrocatalytic hydrogen evolution activity in the presence of water as reported by Rui Cao and co-workers in their Communication (e202114310). The crown ether unit is able to grab water molecules through hydrogen bond interactions. The established water network can play critical roles in assisting proton transfer, leading to improved electrocatalytic activity for the hydrogen evolution reaction, which mimics water-network-assisted proton transfer as found in metalloproteins.

Spherical vs. planar: Steering the electronic communication between Ru nanoparticle and single atom to boost the electrocatalytic hydrogen evolution activity both in acid and alkaline

Steering the electronic structure of a catalyst has been considered as an effective way to boost the electrocatalytic activity of hydrogen evolution reaction (HER). Herein, a core-shell architecture comprising a Ru nanoparticle (NP) encapsulated into an oxyfullerene-like carbon cage decorated with single-atomic RuNx species anchored on nitrogen-doped carbon substrate (RuNP@RuNx-OFC/NC) was constructed. Benefiting from the efficient electronic communication between Ru NP and atomically-distributed Ru site on the carbon cage, the RuNP@RuNx-OFC/NC exhibited outstanding electrocatalytic performance for HER both in acid and alkaline. Experimental and theoretical results demonstrated that the charge transfer from Ru NP to single-atomic Ru could steer the electronic density of Ru sites and thus facilitate the adsorption of hydrogen and dissociation of water. Resultantly, such charge electronic communication effectively reduced the Gibbs free energy, leading to the improved HER activity. The present work would promote the design and construction of efficient electrocatalysts for energy conversion and storage.

Nanoarchitectonics of uniformly distributed noble-metal-free CoP in g-C3N4 via in-situ fabrication for enhanced photocatalytic and electrocatalytic hydrogen production

Developing an efficient, robust and low-budget bifunctional material for hydrogen evolution is a daunting challenge, which has attracted plenty of researchers’ interest. Herein, we report the non-noble metal bifunctional g-C3N4/CN/CoP catalysts in situ formed for both photocatalytic and electrocatalytic hydrogen production through a convenient phosphorization process. It was found that the optimal g-C3N4(90)/CN300/CoP3 composite not only had the best photocatalytic hydrogen production rate (29.78 mmol·g−1·h−1) in the dye sensitization system, but also had an excellent electrocatalytic hydrogen evolution activity, with an overpotential of 221 mV at 10 mA·cm−2. The XRD, FT-IR, TG, et al. confirm the close contact between ZIF-Co and g-C3N4 in the ideal g-C3N4/ZIF-Co precursor could expediently achieve the uniformly distributed CoP to accelerate electron transfer and reduce the recombination rate of charge. This work can provide a novel strategy to fabricate non-noble metal dual-functional materials for photocatalytic and electrocatalytic hydrogen production to solve energy crises and environmental further.

NIR Photothermal-Enhanced Electrocatalytic and Photoelectrocatalytic Hydrogen Evolution by Polyaniline/SnS2 Nanocomposites

A series of polyaniline (PANI)-decorated SnS2 nanoplates (PANI/SnS2) were produced via a hydrothermal method followed by a liquid–solid mixing. The PANI/SnS2 nanocomposites were composed of amorphous PANI and hexagonal-phase SnS2 nanoplates. Infrared thermal images revealed that PANI had an excellent near-infrared (NIR)-induced photothermal effect. Overall, the PANI/SnS2 nanocomposites showed better NIR-enhanced electrocatalytic and photoelectrocatalytic hydrogen evolution activity than bare SnS2 nanoplates. The optimized 4% PANI/SnS2 (which contained 4 wt % PANI) displayed the largest electrochemical double-layer capacitance (Cdl) value (0.85 mF cm–2) and the lowest Tafel slope of 66 mV dec–1 in 0.5 M H2SO4 under NIR irradiation. It was investigated and confirmed that the photothermal effect and the synergistic effects between SnS2 and PANI heterostructure played important roles in promoting electrocatalytic and photoelectrocatalytic hydrogen evolution processes.

Mn-doped NiP: Facile synthesis and enhanced electrocatalytic activity for hydrogen evolution

Mn-doped NiP: Facile synthesis and enhanced electrocatalytic activity for hydrogen evolution

Bimetal phosphide as high efficiency and stable bifunctional electrocatalysts for hydrogen and oxygen evolution reaction in alkaline solution.

The development of low-cost, high-efficiency, and stable bifunctional electrocatalysts for large-scale water electrolysis is very important for the sustainable development of energy. In this paper, the nickel cobalt phosphide (CoNiP) microstructure was prepared by the “in situ growth-ion exchange-phosphating” method. Due to the flake structure and the synergistic effect of the bimetal, the synthesized CoNiP microstructure exhibited high electrocatalytic activity and stability for hydrogen and oxygen evolution in alkaline electrolyte. The optimized CoNiP showed low overpotential of 116 mV at 10 mA cm−2 for hydrogen evolution reaction and 400 mV at 50 mA cm−2 for oxygen evolution reaction in KOH solution. In addition, it exhibited long-term stability at a high constant current density of 100 mA cm−2 for 48 hours at room temperature and for 65 hours at 80 °C without significant degradation. Theoretical results showed that the introduction of Co and P atoms could reduce the reaction barrier and improve the electron transfer ability. This work provides a simple and economical way for the synthesis of electrocatalytic bimetal phosphide catalysts.