Carbon Oxyanion Self‐Transformation on NiFe Oxalates Enables Long‐Term Ampere‐Level Current Density Seawater Oxidation

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(1)

Published: Nov. 23, 2023

Seawater electrolysis is an attractive way of making H2 in coastal areas, and NiFe-based materials are among the top options for alkaline seawater oxidation (ASO). However, ample Cl- can severely corrode catalytic sites lead to limited lifespans. Herein, we report that situ carbon oxyanion self-transformation (COST) from oxalate carbonate on a monolithic NiFe micropillar electrode allows safeguard high-valence metal reaction ASO. In situ/ex studies show spontaneous, timely, appropriate COST safeguards active against attack during ASO even at ampere-level current density (j). Our catalyst shows efficient stable performance, which requires overpotential as low 349 mV attain j 1 A cm-2 . Moreover, with protective surface CO32- exhibits slight activity degradation after 600 h under seawater. This work reports effective design concepts level self-transformation, acting momentous step toward defending seawater-to-H2 conversion systems.

Language: Английский

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Efficient bubble/precipitate traffic enables stable seawater reduction electrocatalysis at industrial-level current densities

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: April 5, 2024

Abstract Seawater electroreduction is attractive for future H 2 production and intermittent energy storage, which has been hindered by aggressive Mg 2+ /Ca precipitation at cathodes consequent poor stability. Here we present a vital microscopic bubble/precipitate traffic system (MBPTS) constructing honeycomb-type 3D robust anti-precipitation seawater reduction (SR), massively/uniformly release small-sized bubbles to almost every corner of the cathode repel precipitates without break. Noticeably, optimal with built-in MBPTS not only enables state-of-the-art alkaline SR performance (1000-h stable operation –1 A cm −2 ) but also highly specialized in catalytically splitting natural into greatest ability. Low amounts after prolonged tests under large current densities reflect genuine efficacy our MBPTS. Additionally, flow-type electrolyzer based on stably functions industrially-relevant 500 mA 150 h while unwaveringly sustaining near-100% Faradic efficiency. Note that estimated price (~1.8 US$/kg H2 even cheaper than US Department Energy’s goal (2 ).

Language: Английский

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A sodium-ion-conducted asymmetric electrolyzer to lower the operation voltage for direct seawater electrolysis

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

Published: July 4, 2023

Hydrogen produced from neutral seawater electrolysis faces many challenges including high energy consumption, the corrosion/side reactions caused by Cl-, and blockage of active sites Ca2+/Mg2+ precipitates. Herein, we design a pH-asymmetric electrolyzer with Na+ exchange membrane for direct electrolysis, which can simultaneously prevent Cl- corrosion precipitation harvest chemical potentials between different electrolytes to reduce required voltage. In-situ Raman spectroscopy density functional theory calculations reveal that water dissociation be promoted catalyst based on atomically dispersed Pt anchored Ni-Fe-P nanowires reduced barrier (by 0.26 eV), thus accelerating hydrogen evolution kinetics in seawater. Consequently, asymmetric exhibits current densities 10 mA cm-2 100 at voltages 1.31 V 1.46 V, respectively. It also reach 400 low voltage 1.66 80 °C, corresponding electricity cost US$1.36 per kg H2 ($0.031/kW h bill), lower than United States Department Energy 2025 target (US$1.4 H2).

Language: Английский

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In Situ Regulating Cobalt/Iron Oxide‐Oxyhydroxide Exchange by Dynamic Iron Incorporation for Robust Oxygen Evolution at Large Current Density

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(5)

Published: Sept. 25, 2023

Abstract The key dilemma for green hydrogen production via electrocatalytic water splitting is the high overpotential required anodic oxygen evolution reaction (OER). Co/Fe‐based materials show superior catalytic OER activity to noble metal‐based catalysts, but still lag far behind state‐of‐the‐art Ni/Fe‐based catalysts probably due undesirable side segregation of FeOOH with poor conductivity and unsatisfied structural durability under large current density. Here, a robust durable catalyst affording densities 500 1000 mA cm −2 at extremely low overpotentials 290 304 mV in base reported. This evolves from amorphous bimetallic FeOOH/Co(OH) 2 heterostructure microsheet arrays fabricated by facile mechanical stirring strategy. Especially, situ X‐ray photoelectron spectroscopy (XPS) Raman analysis decipher rapid reconstruction into dynamically stable Co 1‐x Fe x OOH active phase through iron incorporation CoOOH, which perform as real sites accelerating rate‐determining step supported density functional theory calculations. By coupling MoNi 4 /MoO cathode, self‐assembled alkaline electrolyzer can deliver cell voltage 1.613 V, better than commercial IrO (+) ||Pt/C (‐) most reported transition electrolyzers. work provides feasible strategy exploration design industrial water‐splitting large‐scale production.

Language: Английский

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Materials Design and System Innovation for Direct and Indirect Seawater Electrolysis

ACS Nano, Journal Year: 2023, Volume and Issue: 17(22), P. 22227 - 22239

Published: Nov. 15, 2023

Green hydrogen production from renewably powered water electrolysis is considered as an ideal approach to decarbonizing the energy and industry sectors. Given high-cost supply of ultra-high-purity water, well mismatched distribution sources renewable energies, combining seawater with coastal solar/offshore wind power attracting increasing interest for large-scale green production. However, various impurities in lead corrosive toxic halides, hydroxide precipitation, physical blocking, which will significantly degrade catalysts, electrodes, membranes, thus shortening stable service life electrolyzers. To accelerate development electrolysis, it crucial widen working potential gap between oxygen evolution chlorine reactions develop flexible highly efficient purification technologies. In this review, we comprehensively discuss present challenges, research efforts, design principles direct/indirect aspects materials engineering system innovation. Further opportunities developing advanced integrated electrolyzers are highlighted both low-grade sources.

Language: Английский

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Metal nitrides for seawater electrolysis

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 53(1), P. 163 - 203

Published: Nov. 29, 2023

The current strategies and basic mechanisms of metal nitrides for hydrogen production from seawater are reviewed.

Language: Английский

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Advanced bifunctional catalysts for energy production by electrolysis of earth-abundant water

Fuel, Journal Year: 2023, Volume and Issue: 357, P. 129753 - 129753

Published: Sept. 11, 2023

Language: Английский

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Recent advances of bifunctional electrocatalysts and electrolyzers for overall seawater splitting

Journal of Materials Chemistry A, Journal Year: 2023, Volume and Issue: 12(2), P. 634 - 656

Published: Dec. 2, 2023

This review summarizes advances in bifunctional electrocatalysts and electrolyzers for seawater splitting, including various catalysts ( e.g. , phosphides, chalcogenides, borides, nitrides, (oxy)hydroxides) membrane-based/membrane-less systems.

Language: Английский

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Study of engineering electronic structure modulated non-noble metal oxides for scaled-up alkaline blend seawater splitting

Journal of Energy Chemistry, Journal Year: 2023, Volume and Issue: 86, P. 167 - 179

Published: July 25, 2023

Language: Английский

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Potential technology for seawater electrolysis: Anion-exchange membrane water electrolysis

Chem Catalysis, Journal Year: 2023, Volume and Issue: 3(7), P. 100643 - 100643

Published: May 25, 2023

Language: Английский

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