Unrevealing the Interaction Between Electrode Degradation and Bubble Behaviors in an Anion Exchange Membrane Water Electrolyzer

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 7, 2025

Stainless steel felt has been employed in AEMWE as a combination of oxygen evolution reaction (OER) electrocatalysts and porous transport layers, which are not only easy to prepare but also have excellent OER activity under alkaline conditions. However, by realizing detailed electrochemical analysis multi-scale visualization the bubble behaviors, it is found that combined effect chemical corrosion led constant accumulation metal oxides on stainless fiber surface post-durability compared slow-growing hydroxides after initial activation. Moreover, rougher morphology weaken hydrophilicity cause adjacent bubbles slower detach from electrode more likely fusion. The measured diameter leaving almost doubles, while total number decreases about two-thirds, causing increase plug flow field deteriorating performance long-term stability AEMWE.

Language: Английский

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Deciphering role of dual nickel sites in reconstructed hetero-anionic structure of nickel sulfide for boosted hydrogen evolution reaction

Applied Catalysis B Environment and Energy, Journal Year: 2024, Volume and Issue: 357, P. 124270 - 124270

Published: June 5, 2024

Language: Английский

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Low‐Spin Fe³⁺ Evoked by Multiple Defects with Optimal Intermediate Adsorption Attaining Unparalleled Performance in Water Oxidation

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

Published: Nov. 14, 2024

Abstract Electrocatalytic water splitting is long constrained by the sluggish kinetics of anodic oxygen evolution reaction (OER), and rational spin‐state manipulation holds great promise to break through this bottleneck. Low‐spin Fe 3+ (LS, t 2g 5 e g 0 ) species are identified as highly active sites for OER in theory, whereas it still a formidable challenge construct experimentally. Herein, new strategy demonstrated effective construction LS NiFe‐layered double hydroxide (NiFe‐LDH) introducing multiple defects, which induce coordination unsaturation over thus enlarge their d orbital energy. The as‐obtained catalyst exhibits extraordinary performance with an ultra‐low overpotential 244 mV at industrially required current density 500 mA cm −2 , 110 lower than that conventional NiFe‐LDH high‐spin (HS, 3 2 superior most previously reported NiFe‐based catalysts. Comprehensive experimental theoretical studies reveal configuration effectively reduces adsorption strength O* intermediate compared HS case, thereby altering rate‐determining step from (O* → OOH*) (OH* O*) lowering its energy barrier. This work paves avenue developing efficient spin‐dependent electrocatalysts beyond.

Language: Английский

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Crystal Facets‐Activity Correlation for Oxygen Evolution Reaction in Compositional Complex Alloys

Advanced Science, Journal Year: 2024, Volume and Issue: unknown

Published: July 23, 2024

Compositional complex alloys, including high and medium-entropy alloys (HEAs/MEAs) have displayed significant potential as efficient electrocatalysts for the oxygen evolution reaction (OER), but their structure-activity relationship remains unclear. In particular, basic question of which crystal facets are more active, especially considering surface reconstructions, has yet to be answered. This study demonstrates that lowest index {100} FeCoNiCr MEAs exhibit highest activity. The underlying mechanism associated with facet's low in-plane density, making it easier reconstruction form amorphous structures containing true active species is uncovered. These results validated by experiments on single crystals polycrystal MEAs, well DFT calculations. discoveries contribute a fundamental comprehension in electrocatalysis offer physics-based strategies developing electrocatalysts.

Language: Английский

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Catalytic enhancement and energy dynamics of Cu-doped NiO on 304SS: Mechanisms of oxygen evolution reaction at reduced activation energies

Molecular Catalysis, Journal Year: 2025, Volume and Issue: 576, P. 114929 - 114929

Published: Feb. 21, 2025

Language: Английский

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Chloride‐Mediated Electron Buffering on Ni‐Fe Anodes for Ampere‐Level Alkaline Seawater Electrolysis

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

Published: April 1, 2025

Abstract In water electrolysis, the long‐term stability of anodes is compromised by their degradation under oxidative conditions. This issue becomes more pronounced in seawater where natural chloride ion (Cl − ) induces chlorine evolution reaction (ClER) to produce corrosive byproducts. Herein, a series small organic molecules (SOMs), featuring an aromatic carbon ring with para‐positioned carbonyl groups, are integrated conventional nickel‐iron (Ni‐Fe) based anode. integration triggers unique electron buffering effect address anode seawater‐based electrolytes. It found that preferential adsorption Cl onto SOMs prevents its direct interaction metal active sites. Furthermore, SOM‐Cl serving as group significantly reduces dissolution Fe sites highly environment. As result, SOM‐Cl‐engineered enhances oxygen activity ≈1.7 times compared pure water. addition, rationally designed works stably for over 200 h at high current density 1.3 A cm −2 alkaline electrolyzer (ASE).

Language: Английский

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Regulating d-p Band Center Distance at Metallene-Derived BOx-NiOOH to Unlock Lattice Oxygen for High-Efficient Glycerol Electrooxidation Coupled Hydrogen Evolution

Applied Catalysis B Environment and Energy, Journal Year: 2025, Volume and Issue: unknown, P. 125368 - 125368

Published: April 1, 2025

Language: Английский

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Alkaline electrochemical deposition of Pt for alkaline electrolyzers

International Journal of Hydrogen Energy, Journal Year: 2024, Volume and Issue: 80, P. 261 - 269

Published: July 16, 2024

The development of hydrogen storage and conversion technologies, such as electrolyzers fuel cells, significantly benefits from the electrochemical deposition platinum (Pt). This process is also crucial for creating coatings internal combustion engines electronic devices. Conventionally, Pt occurs in acidic media, which efficiently dissolves salts but necessitates use expensive, corrosion-resistant substrates like noble metals other critical raw materials titanium (Ti). research explores alkaline Pt, aiming to overcome limitations associated with media. study begins developing strategies dissolve commonly used precursors baths into stable complexes suitable environments. Various protocols, including chronoamperometric potentiometric ones, are employed evaluate electrodeposition on nickel (Ni) foams stainless steel meshes, relevant water electrolysis. Optimization parameters carried out enhance evolution reaction (HER) activity resulting electrodes. most HER-active electrodes then tested cathodes (AELs), demonstrating superior performance compared commercially available platinized Ti felts. These advanced AELs can operate at high current densities (≥1 A cm⁻2) cell voltages below 2 V, thereby rivaling state-of-the-art electrolysis systems. Looking forward, presents a sustainable approach usage green production. recovered operating or end-of-life cells be reused restore catalytic electrolysis, ensuring efficient eco-friendly utilization.

Language: Английский

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Boosting the Oxygen Evolution Reaction Performance of Ni‐Fe‐Electrodes by Tailored Conditioning

ChemElectroChem, Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 30, 2024

Abstract To meet the rising demand for green hydrogen, efficient alkaline water electrolysis demands highly active and low‐cost electrocatalysts oxygen evolution reaction (OER). We address this issue by focusing our work on optimizing conditioning of promising Ni‐(Fe)‐based electrodes to improve their electrocatalytic performances. Systematic parameter variation cyclic voltammetry revealed that a large potential window, low scan rate, high number cycles result in improved activation. If time is fixed, rate was found beneficial. A remarkable 47±6 mV drop at 10 mA cm −2 achieved Ni 70 Fe 30 when between −0.35–1.6 V 100 s −1 just min. could demonstrate activation persisted over h , underscoring its enduring efficacy. suggest effect results from growth hydrous hydroxide layer, which supported energy dispersive X‐ray spectroscopy photoelectron spectroscopy. incorporation or dissolution played only minor role differences electrode activation, as demonstrated content electrolyte. Our stresses importance enhancing OER performance explores how catalysts′ effectiveness tailoring oxides.

Language: Английский

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Tuning Stainless Steel Oxide Layers through Potential Cycling─AEM Water Electrolysis Free of Critical Raw Materials

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 16(23), P. 29963 - 29978

Published: May 29, 2024

Anion exchange membrane water electrolyzers (AEMWEs) have an intrinsic advantage over acidic proton through their ability to use inexpensive, stable materials such as stainless steel (SS) catalyze the sluggish oxygen evolution reaction (OER). As such, study of active oxide layers on SS has garnered great interest. Potential cycling is a means create in situ they are readily formed alkaline solutions when exposed elevated potentials. Cycling conditions literature rife with unexplained variations, and complete account how these variations affect activity constitution remains unreported, along influence AEMWE performance. In this paper, we seek fill gap by strategically felt (SSF) electrodes under different scan rates ranges. The SSF anodes were rapidly activated within first 50 cycles, shown 10-fold decline charge transfer resistance, subsequent 1000 cycles tuned metal surface composition. Ni redox couple (RC) increases content, which further enhanced lowering rate, while Fe RC Cr content. Fair OER was uncovered RC, produced toward both hydrogen (HER). This indicates that inert can be become efficient HER electrodes. To effect, single-cell without any traditional catalyst or ionomer generated 1.0 A cm-2 at 1.94 V ± 13.3 mV anode, showing fair performance for cell free critical raw materials.

Language: Английский

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