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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Defect‐Rich High‐Entropy Oxide Nanosheets for Efficient 5‐Hydroxymethylfurfural Electrooxidation

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(37), P. 20253 - 20258

Published: June 26, 2021

High-entropy oxides (HEOs), a new concept of entropy stabilization, exhibit unique structures and fascinating properties, are thus important class materials with significant technological potential. However, the conventional high-temperature synthesis techniques tend to afford micron-scale HEOs low surface area, catalytic activity available is still far from satisfactory because their limited exposed active sites poor intrinsic activity. Here we report low-temperature plasma strategy for preparing defect-rich nanosheets high first time employ them 5-hydroxymethylfurfural (HMF) electrooxidation. Owing structure, abundant oxygen vacancies, quinary (FeCrCoNiCu)3 O4 deliver improved HMF oxidation lower onset potential faster kinetics, outperforming that prepared by method. Our method opens opportunities synthesizing nanostructured great applications.

Language: Английский

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NiCo-Based Electrocatalysts for the Alkaline Oxygen Evolution Reaction: A Review

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(20), P. 12485 - 12509

Published: Sept. 27, 2021

Electrocatalytic water splitting is a sustainable way to produce hydrogen energy, but the oxygen evolution reaction (OER) at anode has sluggish kinetics and low energy conversion efficiency, which major bottleneck for large-scale production. The design synthesis of robust low-cost OER catalysts are crucial OER. NiCo-based electrocatalysts have suitable atomic electronic structures, show high activity stability during process. Recently, significant progress been made in regulating structure composition understanding nature catalysis, especially mechanism, catalytic active sites, structure–activity relationship. In this work, we summarized discussed latest development OER, with particular emphasis on catalyst synthesis, strategies boosting performance, catalysis from experimental theoretical perspectives. some descriptors, relationships based unveiled. Finally, challenges futuristic outlooks improving performance proposed, hope review can provide guidance more efficient electrocatalysts.

Language: Английский

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Schottky Heterojunction Nanosheet Array Achieving High‐Current‐Density Oxygen Evolution for Industrial Water Splitting Electrolyzers

Advanced Energy Materials, Journal Year: 2021, Volume and Issue: 11(46)

Published: Oct. 24, 2021

Abstract Versatile catalyst systems with large current density under industrial conditions are pivotal to give impetus hydrogen energy from fundamental practical applications. Herein, a Schottky heterojunction nanosheet array composed of dispersed NiFe hydroxide nanoparticles and ultrathin NiS nanosheets (NiFe LDH/NiS) is proposed regulate cooperatively mass transport electronic structure for triggering oxygen evolution reaction (OER) activity at high current. In catalytic systems, the rich porosity contributes abundant sites good infiltration electrolyte fast transfer. Furthermore, theoretical calculations reveal coupling LDH onto could tune d‐band center Ni(Fe) atoms binding strength intermediates favorable OER kinetics. Therefore, LDH/NiS exhibits remarkable activity, delivering 1000 mA cm –2 ultralow overpotential 325 mV. Meanwhile, scaled‐up electrodes implemented in an water splitting electrolyzer exhibit stable cell voltage 2.01 V deliver constant 8000 over 80 h, saving 0.215 kWh electricity generate more per cubic meter than commercial Raney Ni electrodes.

Language: Английский

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Phosphorized CoNi₂S₄ Yolk‐Shell Spheres for Highly Efficient Hydrogen Production via Water and Urea Electrolysis

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(42), P. 22885 - 22891

Published: Aug. 5, 2021

Abstract Exploring earth‐abundant electrocatalysts with excellent activity, robust stability, and multiple functions is crucial for electrolytic hydrogen generation. Porous phosphorized CoNi 2 S 4 yolk‐shell spheres (P‐CoNi YSSs) were rationally designed synthesized by a combined hydrothermal sulfidation gas‐phase phosphorization strategy. Benefiting from the strengthened Ni 3+ /Ni 2+ couple, enhanced electronic conductivity, hollow structure, P‐CoNi YSSs exhibit activity durability towards hydrogen/oxygen evolution urea oxidation reactions in alkaline solution, affording low potentials of −0.135 V, 1.512 1.306 V (versus reversible electrode) at 10 mA cm −2 , respectively. Remarkably, when used as anode cathode simultaneously, catalyst merely requires cell voltage 1.544 water splitting 1.402 electrolysis to attain 100 h, outperforming most reported nickel‐based sulfides even noble‐metal‐based electrocatalysts. This work promotes application electrochemical production provides feasible approach urea‐rich wastewater treatment.

Language: Английский

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Reinforcing CoO Covalency via Ce(4f)─O(2p)─Co(3d) Gradient Orbital Coupling for High‐Efficiency Oxygen Evolution

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(30)

Published: April 18, 2023

Rare-earth (RE)-based transition metal oxides (TMO) are emerging as a frontier toward the oxygen evolution reaction (OER), yet knowledge regarding their electrocatalytic mechanism and active sites is very limited. In this work, atomically dispersed Ce on CoO successfully designed synthesized by an effective plasma (P)-assisted strategy model (P-Ce SAs@CoO) to investigate origin of OER performance in RE-TMO systems. The P-Ce SAs@CoO exhibits favorable with overpotential only 261 mV at 10 mA cm-2 robust electrochemical stability, superior individual CoO. X-ray absorption spectroscopy situ Raman reveal that Ce-induced electron redistribution inhibits CoO bond breakage CoOCe unit site. Theoretical analysis demonstrates gradient orbital coupling reinforces covalency Ce(4f)─O(2p)─Co(3d) site optimized Co-3d-eg occupancy, which can balance adsorption strength intermediates turn reach apex theoretical maximum, excellent agreement experimental observations. It believed establishment Ce-CoO set basis for mechanistic understanding structural design high-performance catalysts.

Language: Английский

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Engineering Metallic Heterostructure Based on Ni₃N and 2M‐MoS₂ for Alkaline Water Electrolysis with Industry‐Compatible Current Density and Stability

Advanced Materials, Journal Year: 2021, Volume and Issue: 34(9)

Published: Dec. 30, 2021

Alkaline water electrolysis is commercially desirable to realize large-scale hydrogen production. Although nonprecious catalysts exhibit high electrocatalytic activity at low current density (10-50 mA cm-2 ), it still challenging achieve industrially required over 500 due inefficient electron transport and competitive adsorption between hydroxyl water. Herein, the authors design a novel metallic heterostructure based on nickel nitride monoclinic molybdenum disulfide (Ni3 N@2M-MoS2 ) for extraordinary electrolysis. The Ni3 composite with heterointerface provides two kinds of separated reaction sites overcome steric hindrance hydroxyl/water adsorption. kinetically decoupled adsorption/dissociation conductivity enable production from N oxygen evolution large density. proved be imperative stabilization activation , which can efficiently regulate active electronic states Ni/N atoms around Fermi-level through charge transfer MoMo bonds 2M-MoS2 boost overall splitting. incorporated electrolyzer requires ultralow cell voltage 1.644 V@1000 ≈100% retention 300 h, far exceeding commercial Pt/C║RuO2 (2.41 100 58.2%).

Language: Английский

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Single-Atom and Bimetallic Nanoalloy Supported on Nanotubes as a Bifunctional Electrocatalyst for Ultrahigh-Current-Density Overall Water Splitting

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(2), P. 1167 - 1179

Published: Jan. 5, 2022

Developing exceedingly efficient, cost-effective, and environmentally friendly bifunctional catalysts for the hydrogen evolution reaction (HER) oxygen (OER) especially at high current density is crucial realizing industrial application of electrocatalytic overall water splitting. In this work, non-noble-metal with single Ni atoms, Fe NiFe nanoalloys supported on carbon nanotubes (NiSAFeSA-NixFe/CNT) are rationally designed fabricated. 1 M KOH, optimized NiSAFeSA-Ni50Fe/CNT catalyst affords low overpotentials 64 227 mV 10 mA cm–2 catalyzing HER OER, respectively. Moreover, enables splitting a cell voltage 1.49 V to achieve in KOH. At 1.80 V, as 382 cm–2, which surpasses those most materials reported so far. After simple two-step oxidation rereduction procedure, catalytic performances HER, recover completely their original levels. This work not only provides potential candidate economically but also shows method reactivatable design.

Language: Английский

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Highly Efficient Electrocatalytic Oxygen Evolution Over Atomically Dispersed Synergistic Ni/Co Dual Sites

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(40)

Published: July 27, 2022

Single-atom catalysts (SACs) are being pursued as economical electrocatalysts. However, their low active-site loading, poor interactions, and unclear catalytic mechanism call for significant advances. Herein, atomically dispersed Ni/Co dual sites anchored on nitrogen-doped carbon (a-NiCo/NC) hollow prisms rationally designed synthesized. Benefiting from the dual-metal synergistic obtained a-NiCo/NC sample exhibits superior electrocatalytic activity kinetics towards oxygen evolution reaction. Moreover, density functional theory calculations indicate that strong interactions heteronuclear paired lead to optimization of electronic structure reduced reaction energy barrier. This work provides a promising strategy synthesis high-efficiency dual-site SACs in field electrochemical storage conversion.

Language: Английский

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Synergetic Cobalt‐Copper‐Based Bimetal–Organic Framework Nanoboxes toward Efficient Electrochemical Oxygen Evolution

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(50), P. 26397 - 26402

Published: Oct. 20, 2021

The development of efficient oxygen electrocatalysts and understanding their underlying catalytic mechanism are significant importance for the high-performance energy conversion storage technologies. Herein, we report novel CoCu-based bimetallic metal-organic framework nanoboxes (CoCu-MOF NBs) as promising catalysts toward electrochemical evolution reaction (OER), fabricated via a successive cation ligand exchange strategy. With highly exposed bimetal centers well-designed architecture, CoCu-MOF NBs show excellent OER activity stability, with small overpotential 271 mV at 10 mA cm-2 high turnover frequency value 0.326 s-1 an 300 mV. In combination quasi in situ X-ray absorption fine structure spectroscopy density-functional theory calculations, post-formed oxyhydroxide analogue during is believed to account NBs, where electronic synergy between Co neighbouring Cu atoms promotes O-O bond coupling fast kinetics.

Language: Английский

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