Coordination Engineering of Single‐Atom Catalysts for the Oxygen Reduction Reaction: A Review

Advanced Energy Materials, Journal Year: 2020, Volume and Issue: 11(3)

Published: Nov. 30, 2020

Abstract Future renewable energy supplies and a sustainable environment rely on many important catalytic processes. Single‐atom catalysts (SACs) are attractive because of their maximum atom utilization efficiency, tunable electronic structures, outstanding performance. Of particular note, transition‐metal SACs exhibit excellent activity selectivity for the oxygen reduction reaction (ORR)—an half in fuel cells metal–air batteries as well portable hydrogen peroxide (H 2 O ) production. Although considerable efforts have been made synthesis ORR, regulation coordination environments thus structures still pose big challenge. In this review, strategies manipulating classified into three categories, including center metal atoms, manipulation surrounding connecting to atom, modification geometric configuration support. Finally, some issues regarding future development ORR raised possible solutions proposed.

Language: Английский

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Identification of the Highly Active Co–N₄ Coordination Motif for Selective Oxygen Reduction to Hydrogen Peroxide

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(32), P. 14505 - 14516

Published: Aug. 3, 2022

Electrosynthesis of hydrogen peroxide (H

Language: Английский

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Identification of Fenton-like active Cu sites by heteroatom modulation of electronic density

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(8)

Published: Feb. 14, 2022

Developing heterogeneous catalysts with atomically dispersed active sites is vital to boost peroxymonosulfate (PMS) activation for Fenton-like activity, but how controllably adjust the electronic configuration of metal centers further improve kinetics still remains a great challenge. Herein, we report systematic investigation into heteroatom-doped engineering tuning structure Cu-N4 by integrating electron-deficient boron (B) or electron-rich phosphorus (P) heteroatoms carbon substrate PMS activation. The electron-depleted Cu-N4/C-B found exhibit most oxidation capacity among prepared single-atom catalysts, which at top rankings Cu-based and superior state-of-the-art catalysts. Conversely, electron-enriched Cu-N4/C-P induces decrease in Both experimental results theoretical simulations unravel that long-range interaction B atoms decreases density Cu down-shifts d-band center, thereby optimizes adsorption energy This study provides an approach finely control atomic level expected guide design smart

Language: Английский

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A critical review on latest innovations and future challenges of electrochemical technology for the abatement of organics in water

Applied Catalysis B Environment and Energy, Journal Year: 2023, Volume and Issue: 328, P. 122430 - 122430

Published: Feb. 4, 2023

Updated water directives and ambitious targets like the United Nations' Sustainable Development Goals (SDGs) have emerged in last decade to tackle scarcity contamination. Although numerous strategies been developed remove pollutants, it is still necessary enhance their effectiveness against toxic biorefractory organic molecules. Comprehensive reviews highlighted appealing features of electrochemical technologies, but much progress has made recent years. In this timely review, a critical discussion on latest innovations perspectives most promising tools for wastewater treatment presented. The work describes performance electrocatalytic anodes direct oxidation, oxidation mediated by electrogenerated active chlorine, reduction as well coupled approaches synchronous anodic cathodic processes combined with homogeneous heterogeneous catalysis. section devoted assessment scale-up issues increase technology readiness level.

Language: Английский

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Electrocatalytic Oxygen Reduction to Hydrogen Peroxide: From Homogeneous to Heterogeneous Electrocatalysis

Advanced Energy Materials, Journal Year: 2020, Volume and Issue: 11(15)

Published: Dec. 18, 2020

Abstract Hydrogen peroxide (H 2 O ) is an environmentally friendly oxidant, finding widespread use across the chemical industry, in sanitation and environmental remediation. Currently, H manufactured via anthraquinone process which has a number of disadvantages including nondistributed production, high‐energy consumption, substantial organic by‐product waste, need to transport obtained point‐of‐use. Accordingly, electrochemical synthesis now attracting lot interest as alternative, cost‐effective, small‐scale, distributed technology for manufacture. This review summarizes recent advancements development Homogeneous Heterogeneous catalysts electrocatalytic reduction reaction (ORR) . The basic principles ORR, methodologies investigating ORR are first introduced. Next, production over discussed, with focus on mechanisms factors that influence activity, selectivity, kinetics. Subsequently, breakthroughs catalysts, nonnoble metal‐based nanomaterials, carbon materials, single‐atom described. latter given special attention, since they serve bridge between catalysis catalysis, while also offering excellent performance. Finally, challenges opportunities critically discussed.

Language: Английский

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Cation‐Vacancy‐Enriched Nickel Phosphide for Efficient Electrosynthesis of Hydrogen Peroxides

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(16)

Published: Feb. 22, 2022

Electrocatalytic hydrogen peroxide (H2 O2 ) synthesis via the two-electron oxygen reduction reaction (2e ORR) pathway is becoming increasingly important due to green production process. Here, cationic vacancies on nickel phosphide, as a proof-of-concept regulate catalyst's physicochemical properties, are introduced for efficient H2 electrosynthesis. The as-fabricated Ni (VNi )-enriched Ni2-x P-VNi electrocatalyst exhibits remarkable 2e ORR performance with molar fraction of >95% and Faradaic efficiencies >90% in all pH conditions under wide range applied potentials. Impressively, as-created VNi possesses superb long-term durability over 50 h, suppassing recently reported catalysts Operando X-ray absorption near-edge spectroscopy (XANES) synchrotron Fourier transform infrared (SR-FTIR) combining theoretical calculations reveal that excellent catalytic originates from -induced geometric electronic structural optimization, thus promoting adsorption favored "end-on" configuration. It believed demonstrated cation vacancy engineering an effective strategy toward creating active heterogeneous atomic precision.

Language: Английский

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Atomically Dispersed Cobalt Sites on Graphene as Efficient Periodate Activators for Selective Organic Pollutant Degradation

Environmental Science & Technology, Journal Year: 2021, Volume and Issue: 55(8), P. 5357 - 5370

Published: March 17, 2021

Pollutant degradation via periodate (IO4-)-based advanced oxidation processes (AOPs) provides an economical, energy-efficient way for sustainable pollution control. Although single-atomic metal activation (SMA) can be exploited to optimize the process and understand associated mechanisms governing IO4--based AOPs, studies on this topic are rare. Herein, we demonstrated first instance of using SMA IO4- analysis by employing atomically dispersed Co active sites supported N-doped graphene (N-rGO-CoSA) activators. N-rGO-CoSA efficiently activated organic pollutant over a wide pH range without producing radical species. The species underwent stoichiometric decomposition generate iodate (IO3-) Whereas Co2+ Co3O4 could not drive activation; Co-N coordination exhibited high efficiency. conductive matrix reduced contaminants/electron transport distance/resistance these reactions boosted capacity working in conjunction with centers. N-rGO-CoSA/IO4- system substrate-dependent reactivity that was caused iodyl (IO3·) radicals. Electrochemical experiments decomposed pollutants electron-transfer-mediated nonradical processes, where N-rGO-CoSA/periodate* metastable complexes were predominant oxidants, thereby opening new avenue designing efficient activators selective pollutants.

Language: Английский

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Engineering the Local Atomic Environments of Indium Single‐Atom Catalysts for Efficient Electrochemical Production of Hydrogen Peroxide

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(12)

Published: Jan. 19, 2022

The in-depth understanding of local atomic environment-property relationships p-block metal single-atom catalysts toward the 2 e- oxygen reduction reaction (ORR) has rarely been reported. Here, guided by first-principles calculations, we develop a heteroatom-modified In-based metal-organic framework-assisted approach to accurately synthesize an optimal catalyst, in which single In atoms are anchored combined N,S-dual first coordination and B second supported hollow carbon rods (In SAs/NSBC). SAs/NSBC catalyst exhibits high H2 O2 selectivity above 95 % wide range pH. Furthermore, SAs/NSBC-modified natural air diffusion electrode unprecedented production rate 6.49 mol peroxide gcatalyst-1 h-1 0.1 M KOH electrolyte 6.71 PBS electrolyte. This strategy enables design next-generation high-performance materials, provides practical guidance for electrosynthesis.

Language: Английский

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Selective Electrocatalytic Reduction of Oxygen to Hydroxyl Radicals via 3‐Electron Pathway with FeCo Alloy Encapsulated Carbon Aerogel for Fast and Complete Removing Pollutants

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(18), P. 10375 - 10383

Published: Feb. 19, 2021

We reported the selective electrochemical reduction of oxygen (O2 ) to hydroxyl radicals (. OH) via 3-electron pathway with FeCo alloy encapsulated by carbon aerogel (FeCoC). The graphite shell exposed -COOH is conducive 2-electron for H2 O2 generation stepped 1-electron towards . OH. electrocatalytic activity can be regulated tuning local electronic environment electrons coming from inner alloy. new strategy OH overcomes rate-limiting step over electron transfer initiated reduction-/oxidation-state cycle in Fenton process. Fast and complete removal ciprofloxacin was achieved within 5 min this proposed system, apparent rate constant (kobs up 1.44±0.04 min-1 , which comparable state-of-the-art advanced oxidation processes. degradation almost remains same after 50 successive runs, suggesting satisfactory stability practical applications.

Language: Английский

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Electronically and Geometrically Modified Single‐Atom Fe Sites by Adjacent Fe Nanoparticles for Enhanced Oxygen Reduction

Advanced Materials, Journal Year: 2021, Volume and Issue: 34(5)

Published: Nov. 19, 2021

Fe-N-C materials exhibit excellent activity and stability for oxygen reduction reaction (ORR), as one of the most promising candidates to replace commercial Pt/C catalysts. However, it is challenging unravel features superior ORR originating from materials. In this work, electronic geometric structures isolated sites their correlations with performance are investigated by varying secondary thermal activation temperature a rationally designed NC-supported Fe single-atom catalyst (SAC). The systematic analyses demonstrate significant role coordinated atoms SA metallic nanoparticles (NPs) in altering structure sites. Meanwhile, strong interaction between adjacent NPs can change Theoretical calculations reveal that optimal regulation co-existence narrows energy barriers rate-limiting steps ORR, resulting outstanding performance. This work not only provides fundamental understanding underlying structure-activity relationship, but also sheds light on designing efficient

Language: Английский

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