Interfacial Fe−O−Ni−O−Fe Bonding Regulates the Active Ni Sites of Ni‐MOFs via Iron Doping and Decorating with FeOOH for Super‐Efficient Oxygen Evolution

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(17)

Published: Feb. 11, 2022

The integration of Fe dopant and interfacial FeOOH into Ni-MOFs [Fe-doped-(Ni-MOFs)/FeOOH] to construct Fe-O-Ni-O-Fe bonding is demonstrated the origin remarkable electrocatalytic performance elucidated. X-ray absorption/photoelectron spectroscopy theoretical calculation results indicate that can facilitate distorted coordinated structure Ni site with a short nickel-oxygen bond low coordination number, promote redistribution Ni/Fe charge density efficiently regulate adsorption behavior key intermediates near-optimal d-band center. Here Fe-doped-(Ni-MOFs)/FeOOH shows superior catalytic for OER overpotential 210 mV at 15 mA cm-2 excellent stability ≈3 % attenuation after 120 h cycle test. This study provides novel strategy design high-performance Ni/Fe-based electrocatalysts in alkaline media.

Language: Английский

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Rapid complete reconfiguration induced actual active species for industrial hydrogen evolution reaction

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Oct. 2, 2022

Rational regulation of electrochemical reconfiguration and exploration activity origin are important foundations for realizing the optimization electrocatalyst activity, but rather challenging. Herein, we potentially develop a rapid complete strategy heterostructures CoC2O4 coated by MXene nanosheets (CoC2O4@MXene) during hydrogen evolution reaction (HER) process. The self-assembled CoC2O4@MXene nanotubular structure has high electronic accessibility abundant electrolyte diffusion channels, which favor reconfiguration. Such creates new actual catalytic active species Co(OH)2 transformed from CoC2O4, is coupled with to facilitate charge transfer decrease free energy Volmer step toward fast HER kinetics. reconfigured components require low overpotentials 28 216 mV at 10 1000 mA cm-2 in alkaline conditions decent stability natural seawater. This work gives insights understanding formation opens up way high-performance electrocatalysts.

Language: Английский

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Competitive Coordination‐Oriented Monodispersed Ruthenium Sites in Conductive MOF/LDH Hetero‐Nanotree Catalysts for Efficient Overall Water Splitting in Alkaline Media

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(12)

Published: Jan. 11, 2022

Rational exploration of efficient, inexpensive, and robust electrocatalysts is critical for the efficient water splitting. Conjugated conductive metal-organic frameworks (cMOFs) with multicomponent layered double hydroxides (LDHs) to construct bifunctional heterostructure catalysts are considered as an but complicated strategy. Here, fabrication a cMOF/LDH hetero-nanotree array catalyst (CoNiRu-NT) coupled monodispersed ruthenium (Ru) sites via controllable grafted-growth strategy reported. Rich-amino hexaiminotriphenylene linkers coordinate LDH nanotrunk form cMOF nanobranches, providing numerous anchoring precisely confine stabilize RuN4 sites. Moreover, reduced Ru moieties facilitate H2 O adsorption dissociation, heterointerface between further modifies chemical electronic structures. Optimized CoNiRu-NT displays significant increase in electrochemical water-splitting properties alkaline media, affording low overpotentials 22 mV at 10 mA cm-2 255 20 hydrogen evolution reaction oxygen reaction, respectively. In actual system, drives overall splitting cell voltage 1.47 V reach . This performance comparable that pure noble-metal-based materials superior most reported MOF-based catalysts.

Language: Английский

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Recent progress in metal–organic frameworks (MOFs) for electrocatalysis

Industrial Chemistry and Materials, Journal Year: 2023, Volume and Issue: 1(1), P. 9 - 38

Published: Jan. 1, 2023

Recent progress of metal–organic framework (MOF) based catalysts in the electrocatalytic hydrogen evolution reaction, oxidation oxygen reduction reaction and nitrogen is summarized.

Language: Английский

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Modulating Local Interfacial Bonding Environment of Heterostructures for Energy‐Saving Hydrogen Production at High Current Densities

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(12)

Published: Jan. 8, 2023

Abstract Coupling urea oxidation reaction (UOR) with hydrogen evolution (HER) is an effective energy‐saving technique for generation. However, exploring efficient bifunctional electrocatalysts under high current density still challenging. Herein, hierarchical Fe doped cobalt selenide coupled FeCo layered double hydroxide (Fe‐Co 0.85 Se/FeCo LDH) array as a self‐supported superior heterojunction electrode rationally designed both UOR and HER. The unique heterostructure facilitates electron transfer interface interactions through local interfacial Co‐Se/O‐Fe bonding environment modulation, improving kinetics intrinsic activity. As result, the heterostructured electrocatalyst exhibits ultralow potentials of −0.274 1.48 V to reach 500 mA cm −2 catalyzing HER UOR, respectively. Particularly, full electrolysis system driven by Fe‐Co LDH delivers 300 at relatively low potential 1.57 V, which 150 mV lower than conventional water electrolysis. combination in situ characterization theoretical analysis reveal that active sites adjustable electronic are induced heterojunction, facilitating decomposition stabilization intermediates UOR. This work inspires modulation optimize advanced H 2 production.

Language: Английский

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Ir Nanoparticles Anchored on Metal‐Organic Frameworks for Efficient Overall Water Splitting under pH‐Universal Conditions

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(17)

Published: March 2, 2023

The construction of high-activity and low-cost electrocatalysts is critical for efficient hydrogen production by water electrolysis. Herein, we developed an advanced electrocatalyst anchoring well-dispersed Ir nanoparticles on nickel metal-organic framework (MOF) Ni-NDC (NDC: 2,6-naphthalenedicarboxylic) nanosheets. Benefiting from the strong synergy between MOF through interfacial Ni-O-Ir bonds, synthesized Ir@Ni-NDC showed exceptional electrocatalytic performance evolution reaction (HER), oxygen (OER) overall splitting in a wide pH range, superior to commercial benchmarks most reported electrocatalysts. Theoretical calculations revealed that charge redistribution bridge induced optimization H2 O, OH* H* adsorption, thus leading accelerated electrochemical kinetics HER OER. This work provides new clue exploit bifunctional pH-universal splitting.

Language: Английский

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Tailoring a local acid-like microenvironment for efficient neutral hydrogen evolution

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: July 14, 2023

Electrochemical hydrogen evolution reaction in neutral media is listed as the most difficult challenges of energy catalysis due to sluggish kinetics. Herein, Ir-HxWO3 catalyst readily synthesized and exhibits enhanced performance for reaction. HxWO3 support functioned proton sponge create a local acid-like microenvironment around Ir metal sites by spontaneous injection protons WO3, evidenced spectroscopy electrochemical analysis. Rationalize revitalized lattice-hydrogen species located interface are coupled with Had atoms on metallic surfaces via thermodynamically favorable Volmer-Tafel steps, thereby fast Elaborated demonstrates activity low overpotential 20 mV at 10 mA cm-2 Tafel slope 28 dec-1, which even comparable those acidic environment. The concept exemplified this work offer possibilities tailoring regulate catalytic pathway.

Language: Английский

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Accelerated water activation and stabilized metal-organic framework via constructing triangular active-regions for ampere-level current density hydrogen production

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Oct. 30, 2022

Two-dimensional metal-organic frameworks (MOFs) have been explored as effective electrocatalysts for hydrogen evolution reaction (HER). However, the sluggish water activation kinetics and structural instability under ultrahigh-current density hinder their large-scale industrial applications. Herein, we develop a universal ligand regulation strategy to build well-aligned Ni-benzenedicarboxylic acid (BDC)-based MOF nanosheet arrays with S introducing (S-NiBDC). Benefiting from closer p-band center Fermi level strong electron transferability, S-NiBDC array exhibits low overpotential of 310 mV attain 1.0 A cm-2 high stability in alkaline electrolyte. We speculate newly-constructed triangular "Ni2-S1" motif improved HER active region based on detailed mechanism analysis characterization, enhanced covalency Ni-O bonds by stabilizes structure. Experimental observations theoretical calculations elucidate that such Ni sites distinctly accelerate kinetics, while site readily captures H atom optimal site, boosting whole activity.

Language: Английский

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Electronic Modulation of Metal–Organic Frameworks by Interfacial Bridging for Efficient pH‐Universal Hydrogen Evolution

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 33(1)

Published: Oct. 26, 2022

Abstract Designing well‐defined interfacial chemical bond bridges is an effective strategy to optimize the catalytic activity of metal–organic frameworks (MOFs), but it remains challenging. Herein, a facile in situ growth reported for synthesis tightly connected 2D/2D heterostructures by coupling MXene with CoBDC nanosheets. The multifunctional nanosheets high conductivity and ideal hydrophilicity as bridging carriers can ensure structural stability sufficient exposure active sites. Moreover, Co–O–Ti formed at interface effectively triggers charge transfer modulates electronic structure Co‐active site, which enhances reaction kinetics. As result, optimized CoBDC/MXene exhibits superior hydrogen evolution (HER) low overpotentials 29, 41, 76 mV 10 mA cm −2 alkaline, acidic, neutral electrolytes, respectively, comparable commercial Pt/C. Theoretical calculation demonstrates that bridging‐induced electron redistribution optimizes free energy water dissociation adsorption, resulting improved evolution. This study not only provides novel electrocatalyst efficient HER all pH conditions also opens up new avenue designing highly systems.

Language: Английский

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Stabilizing Low‐Valence Single Atoms by Constructing Metalloid Tungsten Carbide Supports for Efficient Hydrogen Oxidation and Evolution

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(42)

Published: Sept. 2, 2023

Abstract Designing novel single‐atom catalysts (SACs) supports to modulate the electronic structure is crucial optimize catalytic activity, but rather challenging. Herein, a general strategy proposed utilize metalloid properties of trap and stabilize single‐atoms with low‐valence states. A series supported on surface tungsten carbide (M‐WC x , M=Ru, Ir, Pd) are rationally developed through facile pyrolysis method. Benefiting from WC exhibit weak coordination W C atoms, resulting in formation active centers similar metals. The unique metal‐metal interaction effectively stabilizes single atoms improves orbital energy level distribution sites. As expected, representative Ru‐WC exhibits superior mass activities 7.84 62.52 mg Ru −1 for hydrogen oxidation evolution reactions (HOR/HER), respectively. In‐depth mechanistic analysis demonstrates that an ideal dual‐sites cooperative mechanism achieves suitable adsorption balance H ad OH energetically favorable Volmer step. This work offers new guidance precise construction highly SACs.

Language: Английский

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