Anion-Exchange Membrane Water Electrolyzers

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(13), P. 11830 - 11895

Published: April 20, 2022

This Review provides an overview of the emerging concepts catalysts, membranes, and membrane electrode assemblies (MEAs) for water electrolyzers with anion-exchange membranes (AEMs), also known as zero-gap alkaline electrolyzers. Much recent progress is due to improvements in materials chemistry, MEA designs, optimized operation conditions. Research on polymers (AEPs) has focused cationic head/backbone/side-chain structures key properties such ionic conductivity stability. Several approaches, cross-linking, microphase, organic/inorganic composites, have been proposed improve performance chemical mechanical stability AEMs. Numerous AEMs now exceed values 0.1 S/cm (at 60-80 °C), although specifically at temperatures exceeding 60 °C needs further enhancement. The oxygen evolution reaction (OER) still a limiting factor. An analysis thin-layer OER data suggests that NiFe-type catalysts highest activity. There debate active-site mechanism NiFe their long-term be understood. Addition Co increases these catalysts. same hydrogen (HER) shows carbon-supported Pt dominating, PtNi alloys clusters Ni(OH)

Language: Английский

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Torsion strained iridium oxide for efficient acidic water oxidation in proton exchange membrane electrolyzers

Nature Nanotechnology, Journal Year: 2021, Volume and Issue: 16(12), P. 1371 - 1377

Published: Oct. 25, 2021

Language: Английский

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Descriptors for the Evaluation of Electrocatalytic Reactions: d‐Band Theory and Beyond

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 32(4)

Published: Oct. 13, 2021

Abstract Closing the carbon‐, hydrogen‐, and nitrogen cycle with renewable electricity holds promises for mitigation of facing environment energy crisis, along continuing prosperity human society. Descriptors bridge gap between physicochemical factors electrocatalysts their boosted activity serve as guiding principles during rational design electrocatalysts. The optimal adsorption strength key intermediates is potentially accessed under tendentious guidelines proposed by indicators, such d‐band center, Δ G H , E O* coordination number (CN), bond length, etc. Here, in this review, a comprehensive summary recent advances achieved regarding descriptors that aims recycling C/H/N‐containing chemicals offered. review initiated providing necessity development efficient then physics behind center introduced. Then progress relating to guidance reviewed. Following that, an extended discussion experimental or theoretical characterization beyond it provided. Finally, perspectives challenges area are

Language: Английский

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Self‐Supported Electrocatalysts for Practical Water Electrolysis

Advanced Energy Materials, Journal Year: 2021, Volume and Issue: 11(39)

Published: Sept. 1, 2021

Abstract Over the years, significant advances have been made to boost efficiency of water splitting by carefully designing economic electrocatalysts with augmented conductivity, more accessible active sites, and high intrinsic activity in laboratory test conditions. However, it remains a challenge develop earth‐abundant catalysts that can satisfy demands practical electrolysis, is, outstanding all‐pH electrolyte capacity, direct seawater ability, exceptional performance for overall splitting, superior large‐current‐density activity, robust long‐term durability. In this context, considering features increased species loading, rapid charge, mass transfer, strong affinity between catalytic components substrates, easily‐controlled wettability, as well as, enhanced bifunctional performance, self‐supported are presently projected be most suitable contenders massive scale hydrogen generation. review, comprehensive introduction design fabrication an emphasis on deposited nanostructured catalysts, selection various methods provided. Thereafter, recent development promising applications is reviewed from aforementioned aspects. Finally, brief conclusion delivered challenges perspectives relating promotion sustainable large‐scale production discussed.

Language: Английский

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Critical Review, Recent Updates on Zeolitic Imidazolate Framework‐67 (ZIF‐67) and Its Derivatives for Electrochemical Water Splitting

Advanced Materials, Journal Year: 2021, Volume and Issue: 34(11)

Published: Nov. 30, 2021

Design and construction of low-cost electrocatalysts with high catalytic activity long-term stability is a challenging task in the field catalysis. Metal-organic frameworks (MOF) are promising candidates as precursor materials development highly efficient for energy conversion storage applications. This review starts summary basic concepts key evaluation parameters involved electrochemical water-splitting reaction. Then, different synthesis approaches reported cobalt-based Zeolitic imidazolate framework (ZIF-67) its derivatives critically reviewed. Additionally, several strategies employed to enhance electrocatalytic ZIF-67-based discussed detail. The present provides succinct insight into ZIF-67 (oxides, hydroxides, sulfides, selenides, phosphide, nitrides, telluride, heteroatom/metal-doped carbon, noble metal-supported derivatives) oxygen evolution reaction (OER), hydrogen (HER), overall water splitting Finally, this concludes associated challenges perspectives on developing best economic, durable materials.

Language: Английский

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The Significance of Properly Reporting Turnover Frequency in Electrocatalysis Research

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(43), P. 23051 - 23067

Published: Sept. 15, 2021

For decades, turnover frequency (TOF) has served as an accurate descriptor of the intrinsic activity a catalyst, including those in electrocatalytic reactions involving both fuel generation and consumption. Unfortunately, most recent reports this area, TOF is often not properly reported or at all, contrast to overpotentials benchmarking current density. The density significant determining apparent activity, but it affected by catalyst-centric parasitic reactions, electrolyte-centric competing capacitance. Luckily, calculated can precisely give free from these phenomena electrocatalysis. In Viewpoint we ask: 1) What makes commonly used markers unsuitable for determination? 2) How reflect activity? 3) Why still underused electrocatalysis? 4) methods are 5) essential more calculation TOF? Finally, significance normalizing Faradaic efficiency (FE) stressed our views on development universal analytical tools determine exact number active sites real surface area all kinds materials.

Language: Английский

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Water electrolysis

Nature Reviews Methods Primers, Journal Year: 2022, Volume and Issue: 2(1)

Published: Oct. 27, 2022

Language: Английский

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Construction of Zn-doped RuO2 nanowires for efficient and stable water oxidation in acidic media

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

Published: May 2, 2023

Abstract Oxygen evolution reaction catalysts capable of working efficiently in acidic media are highly demanded for the commercialization proton exchange membrane water electrolysis. Herein, we report a Zn-doped RuO 2 nanowire array electrocatalyst with outstanding catalytic performance oxygen under conditions. Overpotentials as low 173, 304, and 373 mV achieved at 10, 500, 1000 mA cm −2 , respectively, robust stability reaching to h 10 . Experimental theoretical investigations establish clear synergistic effect Zn dopants vacancies on regulating binding configurations oxygenated adsorbates active centers, which then enables an alternative Ru−Zn dual-site oxide path reaction. Due change pathways, energy barrier rate-determining step is reduced, over-oxidation Ru sites alleviated. As result, activity significantly enhanced.

Language: Английский

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Essentials of High Performance Water Electrolyzers – From Catalyst Layer Materials to Electrode Engineering

Advanced Energy Materials, Journal Year: 2021, Volume and Issue: 11(44)

Published: Oct. 13, 2021

Abstract Proton‐exchange membrane water electrolyzers (PEMWEs) will play a key role in future sustainable hydrogen production for mobility, households or chemical industry. Yet, the anode PEMWEs, where pivotal oxygen evolution reaction takes place, needs further improvement terms of performance and cost. Both catalyst materials electrode structure have to be optimized order inhibit degradation reduce noble metal loadings. This review focuses on holistic approach, covering all material, structure, transport layers within framework an overall design, which not only optimizes but also, components conjunction. defines goals metrics PEMWEs power density durability anode. Moreover, it summarizes manufacturing techniques approaches that chance upscaled meet megawatt deployment PEMWEs. The different aspects described jointly this such as novel system with higher intrinsic structural graded porous shall help advance next generation electrodes.

Language: Английский

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Crystalline-amorphous interface of mesoporous Ni2P @ FePOxHy for oxygen evolution at high current density in alkaline-anion-exchange-membrane water-electrolyzer

Applied Catalysis B Environment and Energy, Journal Year: 2022, Volume and Issue: 306, P. 121127 - 121127

Published: Jan. 21, 2022

Language: Английский

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