Advanced Transition Metal‐Based OER Electrocatalysts: Current Status, Opportunities, and Challenges

Small, Journal Year: 2021, Volume and Issue: 17(37)

Published: June 10, 2021

Abstract Oxygen evolution reaction (OER) is an important half‐reaction involved in many electrochemical applications, such as water splitting and rechargeable metal–air batteries. However, the sluggish kinetics of its four‐electron transfer process becomes a bottleneck to performance enhancement. Thus, rational design electrocatalysts for OER based on thorough understanding mechanisms structure‐activity relationship vital significance. This review begins with introduction which include conventional adsorbate mechanism lattice‐oxygen‐mediated mechanism. The pathways related intermediates are discussed detail, several descriptors greatly assist catalyst screen optimization summarized. Some parameters suggested measurement criteria also mentioned discussed. Then, recent developments breakthroughs experimental achievements transition metal‐based reviewed reveal novel principles. Finally, some perspectives future directions proposed further catalytic enhancement deeper design. It believed that iterative improvements fundamental principles essential realize applications efficient energy storage conversion technologies.

Language: Английский

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Recent Progress in Advanced Electrocatalyst Design for Acidic Oxygen Evolution Reaction

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(50)

Published: March 21, 2021

Abstract Proton exchange membrane (PEM) water electrolyzers hold great significance for renewable energy storage and conversion. The acidic oxygen evolution reaction (OER) is one of the main roadblocks that hinder practical application PEM electrolyzers. Highly active, cost‐effective, durable electrocatalysts are indispensable lowering high kinetic barrier OER to achieve boosted kinetics. To date, a wide spectrum advanced has been designed synthesized enhanced performance, though Ir Ru based nanostructures still represent state‐of‐the‐art catalysts. In this Progress Report, recent research progress in improved performance summarized. First, fundamental understanding about including mechanisms atomic rational design efficient discussed. Thereafter, an overview synthesis provided terms catalyst category, i.e., metallic (Ir based), precious metal oxides, nonprecious carbon nanomaterials. Finally, perspectives future development from aspects mechanism investigation more electrocatalyst design.

Language: Английский

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Fast site-to-site electron transfer of high-entropy alloy nanocatalyst driving redox electrocatalysis

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: Oct. 28, 2020

Abstract Designing electrocatalysts with high-performance for both reduction and oxidation reactions faces severe challenges. Here, the uniform ultrasmall (~3.4 nm) high-entropy alloys (HEAs) Pt 18 Ni 26 Fe 15 Co 14 Cu 27 nanoparticles are synthesized by a simple low-temperature oil phase strategy at atmospheric pressure. The /C catalyst exhibits excellent electrocatalytic performance hydrogen evolution reaction (HER) methanol (MOR). shows overpotential of 11 mV current density 10 mA cm −2 , activity (10.96 A mg −1 −0.07 V vs. reversible electrode) stability in alkaline medium. Furthermore, it is also efficient (15.04 ) ever reported MOR solution. Periodic DFT calculations confirm multi-active sites HER on HEA surface as key factor proton intermediate transformation. Meanwhile, construction surfaces supplies fast site-to-site electron transfer processes.

Language: Английский

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Oxygen Evolution/Reduction Reaction Catalysts: From In Situ Monitoring and Reaction Mechanisms to Rational Design

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(9), P. 6257 - 6358

Published: March 21, 2023

The oxygen evolution reaction (OER) and reduction (ORR) are core steps of various energy conversion storage systems. However, their sluggish kinetics, i.e., the demanding multielectron transfer processes, still render OER/ORR catalysts less efficient for practical applications. Moreover, complexity catalyst–electrolyte interface makes a comprehensive understanding intrinsic mechanisms challenging. Fortunately, recent advances in situ/operando characterization techniques have facilitated kinetic monitoring under conditions. Here we provide selected highlights mechanistic studies with main emphasis placed on heterogeneous systems (primarily discussing first-row transition metals which operate basic conditions), followed by brief outlook molecular catalysts. Key sections this review focused determination true active species, identification sites, reactive intermediates. For in-depth insights into above factors, short overview metrics accurate characterizations is provided. A combination obtained time-resolved information reliable activity data will then guide rational design new Strategies such as optimizing restructuring process well overcoming adsorption-energy scaling relations be discussed. Finally, pending current challenges prospects toward development homogeneous presented.

Language: Английский

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Oxygen‐Incorporated NiMoP Nanotube Arrays as Efficient Bifunctional Electrocatalysts For Urea‐Assisted Energy‐Saving Hydrogen Production in Alkaline Electrolyte

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 31(43)

Published: July 29, 2021

Abstract To couple hydrogen evolution reaction (HER) with urea oxidation (UOR) is a promising approach to produce H 2 reduced energy consumption. However, the development of low‐cost and high‐performance bifunctional electrocatalyst toward HER UOR still challenge. In this work, oxygen‐incorporated nickel molybdenum phosphide nanotube arrays are synthesized on foam (O‐NiMoP/NF) via electrodeposition accompanied in‐situ template etching. Benefiting from modulated electronic structure array architecture O‐NiMoP, self‐supporting O‐NiMoP/NF electrodes demonstrate highly efficient catalytic activity UOR. Particularly, in (HER||UOR) coupled system for production, significantly cell voltage 1.55 V obtained at current density 50 mA cm –2 , which about 300 mV lower than that conventional water electrolysis. Density functional theory calculations reveal remarkable activities originated Ni sites environment induced by Mo, P O atoms, facilitate dissociation during balance adsorption/desorption intermediates The Ni‐based phosphides as HER||OER provides new enabling energy‐saving production.

Language: Английский

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Ni2P/NiMoP heterostructure as a bifunctional electrocatalyst for energy-saving hydrogen production

eScience, Journal Year: 2021, Volume and Issue: 1(1), P. 69 - 74

Published: Sept. 21, 2021

Electrochemical water splitting is a sustainable and feasible strategy for hydrogen production but hampered by the sluggish anodic oxygen evolution reaction (OER). Herein, an effective approach introduced to significantly decrease cell voltage replacing OER with urea oxidation (UOR). A Ni2P/NiMoP nanosheet catalyst hierarchical architecture uniformly grown on nickel foam (NF) substrate through simple hydrothermal phosphorization method. The achieves impressive HER activity, low overpotential of only 22 mV at 10 mA cm–2 Tafel slope 34.5 dec–1. In addition, reduced from 1.49 V 1.33 after introduction 0.33 M urea. Notably, two-electrode electrolyzer employing as bifunctional exhibits current density 1.35 excellent long-term durability 80 h.

Language: Английский

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Multi‐Sites Electrocatalysis in High‐Entropy Alloys

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 31(47)

Published: Aug. 26, 2021

Abstract High‐entropy alloys (HEAs) have attracted widespread attention in electrocatalysis due to their unique advantages (adjustable composition, complex surface, high tolerance, etc.). They allow for the formation of new and tailorable active sites multiple elements adjacent each other, interaction can be tailored by rational selection element configuration composition. However, it needs further explored catalyst design, elements, determination sites. This review article focuses on important progress multi‐sites HEAs. The classification is done basis catalytic reaction, including hydrogen evolution oxygen reduction alcohol oxidation carbon dioxide nitrogen reaction. Based experiments theories, a more in‐depth exploration activity HEAs will conducted, (the special role catalysis) effect. provide design some reactions, adjust compositions improve intrinsic activity. Furthermore, remaining challenges future directions promising research fields are also provided.

Language: Английский

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Rational Design of Better Hydrogen Evolution Electrocatalysts for Water Splitting: A Review

Advanced Science, Journal Year: 2022, Volume and Issue: 9(18)

Published: April 18, 2022

Abstract The excessive dependence on fossil fuels contributes to the majority of CO 2 emissions, influencing climate change. One promising alternative is green hydrogen, which can be produced through water electrolysis from renewable electricity. However, variety and complexity hydrogen evolution electrocatalysts currently studied increases difficulty in integration catalytic theory, catalyst design preparation, characterization methods. Herein, this review first highlights principles for reaction (HER) electrocatalysts, presenting thermodynamics, kinetics, related electronic structural descriptors HER. Second, reasonable design, mechanistic understanding, performance enhancement are deeply discussed based intrinsic extrinsic effects. Third, recent advancements electrocatalytic splitting technology further briefly. Finally, challenges perspectives development highly efficient proposed.

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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Regulating electronic states of nitride/hydroxide to accelerate kinetics for oxygen evolution at large current density

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

Published: April 4, 2023

Rational design efficient transition metal-based electrocatalysts for oxygen evolution reaction (OER) is critical water splitting. However, industrial water-alkali electrolysis requires large current densities at low overpotentials, always limited by intrinsic activity. Herein, we report hierarchical bimetal nitride/hydroxide (NiMoN/NiFe LDH) array as model catalyst, regulating the electronic states and tracking relationship of structure-activity. As-activated NiMoN/NiFe LDH exhibits industrially required density 1000 mA cm-2 overpotential 266 mV with 250 h stability OER. Especially, in-situ electrochemical spectroscopic reveals that heterointerface facilitates dynamic structure to optimize structure. Operando impedance spectroscopy implies accelerated OER kinetics intermediate due fast charge transport. The mechanism revealed combination theoretical experimental studies, indicating as-activated follows lattice oxidation kinetics. This work paves an avenue develop catalysts via tuning states.

Language: Английский

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