Synergistic Atomic Environment Optimization of Nickel–Iron Dual Sites by Co Doping and Cr Vacancy for Electrocatalytic Oxygen Evolution

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

The dual-site synergistic catalytic mechanism on NiFeOOH suggests weak adsorption of Ni sites and strong Fe limited its activity toward alkaline oxygen evolution reaction (OER). Large-scale density functional theory (DFT) calculations confirm that Co doping can increase adsorption, while the metal vacancy reduce adsorption. combined two factors further modulate atomic environment optimize free energy oxygen-containing intermediates, thus enhancing OER activity. Accordingly, we used Cr vacancies to fabricate an amorphous catalyst VCr,Co-NiFeOOH. It provides overpotential 239 mV at 100 mA cm–2 high stability over 500 h with a ∼98% potential retention. resulting water electrolyzer based anion exchange membrane (AEM) exhibits remarkable performance 1 A 1.68 V in M KOH. XPS, soft-XAS, XANES Bader charge analysis results reveal regulation local microenvironment valence state by doping, improving sites. alleviate DFT effect redistribute Ni/Fe sites, d-band center Fe, endow Ni–Fe dual barrier rate-determining step.

Language: Английский

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Tailoring Electronic and Morphology Features of Iron‐Doped Ni₂P Nanoflowers for Enhanced Ammonia Electrosynthesis in Solid Electrolyte Reactors

Advanced Energy Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 13, 2025

Abstract Electrochemical nitrate (NO 3 − ) reduction to ammonia (NH presents a promising route for both wastewater treatment and generation but still suffers from sluggish catalytic activity, insufficient mass transfer, the reliance on high‐concentration supporting electrolytes. This work reports an innovative efficient electrosynthesis reactor by integrating self‐assembled iron‐doped Ni 2 P (Fe‐Ni P/NF) nanoflower cathode with solid‐electrolyte (SE). The SE design eliminates need electrolytes, providing highly ion‐conducting pathway enabling direct production of NH NO . Through tailoring electronic surface characteristics Fe‐Ni P/NF, this achieves complete reduction, 96.7% selectivity, 81.8% faradaic efficiency concentration 100 m at current density mA −2 Density functional theory (DFT) calculations reveal that phosphating Fe doping synergistically enhance adsorption increase availability active hydrogen, thus favoring low energy barrier 0.695 eV. Additionally, superhydrophilicity P/NF catalyst promotes transfer facilitating electrolyte access ensuring rapid gas bubble release. study provides sustainable scalable method converting ‐laden into valuable products.

Language: Английский

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Boosting oxygen evolution reaction activity and durability of FeOOH-MOF composite at industrial-grade current densities by a facile corrosion strategy

Applied Catalysis B Environment and Energy, Journal Year: 2025, Volume and Issue: 371, P. 125221 - 125221

Published: March 3, 2025

Language: Английский

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Oxygen Plasma Triggered Co‐O‐Fe Motif in Prussian Blue Analogue for Efficient and Robust Alkaline Water Oxidation

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 16, 2024

In the context of oxygen evolution reaction (OER), construction high-valence transition metal sites to trigger lattice oxidation mechanism is considered crucial for overcoming performance limitations traditional adsorbate mechanism. However, dynamic during poses significant challenges stability sites, particularly in high-current-density water-splitting systems. Here, we have successfully constructed Co-O-Fe catalytic active motifs cobalt-iron Prussian blue analogs (CoFe-PBA) through plasma bombardment, effectively activating reactivity while sustaining robust stability. Our spectroscopic and theoretical studies reveal that bridged enable a unique double-exchange interaction between Co Fe atoms, promoting formation species as OER centers maintaining low-valence state, preventing its dissolution. The resultant catalyst (CoFe-PBA-30) requires an overpotential only 276 mV achieve 1000 mA cm

Language: Английский

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NiFe‐Based Electrocatalysts for Alkaline Oxygen Evolution: Challenges, Strategies, and Advances Toward Industrial‐Scale Deployment

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 2, 2024

Abstract Developing high‐efficiency alkaline water splitting technology holds great promise in potentially revolutionizing the traditional petrochemical industry to a more sustainable hydrogen economy. Importantly, oxygen evolution reaction (OER) accompanied at anode is considered as critical bottleneck terms of both complicated mechanism and sluggish kinetics, requiring rational design OER electrocatalysts elucidate structure‐performance relationship reduce applied overpotential. As benchmarked non‐precious metal candidate, NiFe‐based have gained enormous attention due low‐cost, earth‐abundance, remarkable intrinsic activity, which are expected be implemented industrial splitting. In this contribution, comprehensive overview provided, starting with fundamental mechanisms, evaluation metrics, synthetic protocols. Subsequently, basic principles corresponding regulatory strategies summarized following sequence substrate‐catalyst‐electrolyte efficient robust toward industrial‐scale deployment. Perspectives on remaining challenges instructive opportunities booming field finally discussed.

Language: Английский

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Amorphous Ni(OH)₂ Coated Cu Dendrites with Superaerophobic Interface for Bipolar Hydrogen Production Assisted with Formaldehyde Oxidation

Small, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 13, 2025

Abstract Since formaldehyde oxidation reaction (FOR) can release H 2 , it is attractive to construct a bipolar hydrogen production system consisting of FOR and evolution (HER). Although copper‐based catalysts have attracted much attention due their low cost high activity, the performance enhancement mechanism lacks in‐depth investigation. Here, an amorphous‐crystalline catalyst amorphous nickel hydroxide‐coated copper dendrites on foam (Cu@Ni(OH) /CF) prepared. The modification Ni(OH) resulted in hydrophilic aerophobic states Cu@Ni(OH) /CF surface, facilitating transport liquid‐phase species electrode surface accelerating . Open circuit potential (OCP) density functional theory (DFT) calculations indicate that this core–shell structure facilitates adsorption HCHO OH − In addition, catalytic pathway are investigated through situ FTIR DFT calculations, results showed lowered energy barrier for C─H bond breaking H─H formation. HER//FOR system, Pt/C//Cu@Ni(OH) provide current 0.5 A cm −2 at 0.36 V achieve efficient stable production. This work offers new ideas designing electrocatalysts assisted with oxidation.

Language: Английский

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Isomeric Poly(arylene piperidinium) Electrolyte Membranes with High Alkaline Durability

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 26, 2025

Abstract The isomerization strategy is employed to enhance the alkaline stability of poly(arylene piperidinium)s (PAP) while maintaining monomer commerciality and polymer architecture tunability. Isomeric piperidinium) ( i ‐PAP) exhibits improved alkali resistance relative conventional PAP, as evidenced by ex situ in cell durability tests. Following treatment 10 m aqueous NaOH at 80 °C for 360 h or operation 0.4 A cm −2 100 an anion exchange membrane fuel (AEMFC) prototype, decomposition piperidinium moieties ‐PAP ≈50% that observed PAP. Moreover, through a copolymerization strategy, ‐PAP‐88 membrane, which has suppressed water absorption, reaches peak power density 1.44 W demonstrates 310 h. Furthermore, noble metal‐free (anode) AEM electrolyzer (AEMWE) achieves high current 6.43 cm⁻ 2 2.0 V excellent Faradaic efficiency 98.3%. This study highlights designing alkali‐stable polyelectrolytes mitigate degradation during electrochemical devices.

Language: Английский

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The role of Fe incorporation into Ni-MOF-74 derived oxygen evolution electrocatalysts for anion exchange membrane water electrolysis

EES Catalysis, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

The Fe uptake influence on Ni-MOF-74 derived oxygen evolution electrocatalysts is studied bridging operando XAS studies with implementation in AEM-WE.

Language: Английский

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Strategies to maximize the oxygen evolution reaction in layered double hydroxides by electronic defect engineering

eScience, Journal Year: 2025, Volume and Issue: unknown, P. 100380 - 100380

Published: Feb. 1, 2025

Language: Английский

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Built-in electric field engineering of MoO2-Ni heterostructure by P3p-Mo4d-Tm4f orbitals hybridization for efficient industrial-level hydrogen production

Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: unknown, P. 160921 - 160921

Published: Feb. 1, 2025

Language: Английский

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