Boosting Oxygen Electrocatalytic Activity of Fe–N–C Catalysts by Phosphorus Incorporation

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(6), P. 3647 - 3655

Published: Feb. 6, 2023

Nitrogen-doped graphitic carbon materials hosting single-atom iron (Fe-N-C) are major non-precious metal catalysts for the oxygen reduction reaction (ORR). The nitrogen-coordinated Fe sites described as first coordination sphere. As opposed to good performance in ORR, that evolution (OER) is extremely poor due sluggish O-O coupling process, thus hampering practical applications of rechargeable zinc (Zn)-air batteries. Herein, we succeed boosting OER activity Fe-N-C by additionally incorporating phosphorus atoms into second sphere, here denoted P/Fe-N-C. resulting material exhibits excellent 0.1 M KOH with an overpotential low 304 mV at a current density 10 mA cm-2. Even more importantly, they exhibit remarkably small ORR/OER potential gap 0.63 V. Theoretical calculations using first-principles functional theory suggest enhances electrocatalytic balancing *OOH/*O adsorption FeN4 sites. When used air cathode Zn-air battery, P/Fe-N-C delivers charge-discharge high peak power 269 mW cm-2, highlighting its role state-of-the-art bifunctional electrocatalyst.

Language: Английский

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Ru–Co Pair Sites Catalyst Boosts the Energetics for the Oxygen Evolution Reaction

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(32)

Published: May 31, 2022

Abstract Manipulating the coordination environment of active center via anion modulation to reveal tailored activity and selectivity has been widely achieved, especially for carbon‐based single‐atom site catalysts (SACs). However, tuning ligand fields by single‐site metal cation regulation identifying effects on resulting electronic configuration is seldom explored. Herein, we propose a Ru strategy engineer properties constructing Ru/LiCoO 2 SAC with atomically dispersed Ru−Co pair sites. Benefitting from strong coupling between Co sites, catalyst possesses an enhanced electrical conductivity achieves near‐optimal oxygen adsorption energies. Therefore, optimized delivers superior evolution reaction (OER) low overpotential, high mass 1000 A g oxide −1 at small overpotential 335 mV, excellent long‐term stability. It also exhibits rapid kinetics rate capability outstanding durability in zinc–air battery.

Language: Английский

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Microenvironment Engineering of Single/Dual‐Atom Catalysts for Electrocatalytic Application

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(31)

Published: Feb. 23, 2023

Single/dual-metal atoms supported on carbon matrix can be modulated by coordination structure and neighboring active sites. Precisely designing the geometric electronic uncovering structure-property relationships of single/dual-metal confront with grand challenges. Herein, this review summarizes latest progress in microenvironment engineering single/dual-atom sites via a comprehensive comparison single-atom catalyst (SACs) dual-atom catalysts (DACs) term design principles, modulation strategy, theoretical understanding structure-performance correlations. Subsequently, recent advances several typical electrocatalysis process are discussed to get general reaction mechanisms finely-tuned SACs DACs. Finally, full-scaled summaries challenges prospects given for This will provide new inspiration development atomically dispersed electrocatalytic application.

Language: Английский

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Engineering 3d–2p–4f Gradient Orbital Coupling to Enhance Electrocatalytic Oxygen Reduction

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(42)

Published: Sept. 10, 2022

The development of highly efficient and economical materials for the oxygen reduction reaction (ORR) plays a key role in practical energy conversion technologies. However, intrinsic scaling relations exert thermodynamic inhibition on realizing active ORR electrocatalysts. Herein, novel feasible gradient orbital coupling strategy tuning performance through construction Co 3d-O 2p-Eu 4f unit sites Eu2 O3 -Co model is proposed. Through coupling, pristine ionic property between Eu O atoms assigned with increased covalency, which optimizes eg occupancy sites, weakens OO bond, thus ultimately breaking relation *OOH *OH at Co-O-Eu sites. optimized catalyst displays onset half-wave potential 1.007 0.887 V versus reversible hydrogen electrode, respectively, are higher than those commercial Pt/C most Co-based catalysts ever reported. In addition, found to possess superior selectivity durability. It also reveals better cell noble-metal Zn-air batteries terms high power/energy densities long cycle life. This study provides new perspective electronic modulation by 3d-2p-4f coupling.

Language: Английский

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Proximity Electronic Effect of Ni/Co Diatomic Sites for Synergistic Promotion of Electrocatalytic Oxygen Reduction and Hydrogen Evolution

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 33(4)

Published: Nov. 13, 2022

Abstract The modulation effect manifests an encouraging potential to enhance the performance of single‐atom catalysts; however, in‐depth study about this for isolated diatomic sites (DASs) remains a great challenge. Herein, proximity electronic (PEE) Ni/Co DASs is proposed that anchored in N‐doped carbon (N‐C) substrate (NiCo DASs/N‐C) synergistic promoting electrocatalytic oxygen reduction reaction (ORR) and hydrogen evolution (HER). Benefiting from PEE adjacent Ni by four nitrogen (Ni‐N 4 ) moiety, NiCo DASs/N‐C catalyst exhibits superior ORR HER activity. In situ characterization results suggest Co (Co‐N as main active site O 2 adsorption‐activation process, which promotes formation key *OOH desorption *OH intermediate accelerate multielectron kinetics. Theoretical calculation reveals Ni‐N modulator can effectively adjust localization Co‐N site, *H adsorption on thereby boosting process significantly. This opens new opportunity rationally regulating catalytic centers well provides guidance designing high‐efficiency bifunctional electrocatalysts promising applications.

Language: Английский

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Asymmetric CoN₃P₁ Trifunctional Catalyst with Tailored Electronic Structures Enabling Boosted Activities and Corrosion Resistance in an Uninterrupted Seawater Splitting System

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

Published: July 5, 2022

Employing seawater splitting systems to generate hydrogen can be economically advantageous but still remains challenging, particularly for designing efficient and high Cl- -corrosion resistant trifunctional catalysts toward the oxygen reduction reaction (ORR), evolution (OER), (HER). Herein, single CoNC with well-defined symmetric CoN4 sites are selected as atomic platforms electronic structure tailoring. Density function theory reveals that P-doping into lead formation of asymmetric CoN3 P1 symmetry-breaking structures, enabling affinity strong oxygen-containing intermediates, moderate H adsorption, weak adsorption. Thus, ORR/OER/HER activities stability optimized simultaneously resistance. The based catalyst boosted performance endows seawater-based Zn-air batteries (S-ZABs) superior long-term over 750 h allows operate continuously 1000 h. A self-driven powered by S-ZABs gives ultrahigh H2 production rates 497 μmol h-1 . This work is first advance scientific understanding competitive adsorption mechanism between intermediates from perspective structure, paving way synthesis

Language: Английский

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Regulating the N Coordination Environment of Co Single-Atom Nanozymes for Highly Efficient Oxidase Mimics

Nano Letters, Journal Year: 2023, Volume and Issue: 23(4), P. 1505 - 1513

Published: Feb. 3, 2023

Single-atom catalysts with well-defined atomic structures and precisely regulated coordination environments have been recognized as potential substitutes for natural metalloenzymes. Inspired by the metal structure of enzymes, we show here that oxidase-like activity single-atom Co greatly depends on their local N around catalytic sites. We synthesized a series different nitrogen numbers (Co–Nx(C), x = 2, 3, 4) demonstrated could be effectively tailored fine-tuning coordination. Among studied catalysts, Co–N3(C) three-coordinate atoms shows optimum oxygen adsorption robust reactive species (ROS) generation, thus presenting preferable activity. This work facilitates future development rational nanozyme designs targeting reactions at level.

Language: Английский

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Neodymium‐Evoked Valence Electronic Modulation to Balance Reversible Oxygen Electrocatalysis

Advanced Energy Materials, Journal Year: 2022, Volume and Issue: 13(2)

Published: Nov. 23, 2022

Abstract Suffering from the competition adsorption between oxygen reduction reaction (ORR) and evolution (OER), development of high‐efficiency electrocatalysts with bifunctional properties still remains a challenge. Herein, novel effective neodymium‐evoked valence electronic perturbation strategy to improve balance reversible electrocatalysis metallic cobalt sites is proposed. To heighten coupling Nd Co, metal‐organic‐framework‐induced method chosen prepare target catalyst atomic Nd‐doped Co on an N‐doped carbon substrate. The as‐prepared presents excellent electrocatalytic low overpotential 288 mV at 10 mA cm −2 for OER high half‐wave potential 0.85 V ORR. robust stabilities both ORR are also proven. electrochemical in situ Raman spectra confirm surface dynamic change transformation intermediates by noting formation Co–OOH. Theoretical calculations verify that balanced owing strong 3d‐Nd 4f orbital effect below Fermi level. Moreover, practicability further demonstrated solid‐state rechargeable Zn‐Air batteries, which exhibit large power density long cycling life.

Language: Английский

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Review of Carbon Support Coordination Environments for Single Metal Atom Electrocatalysts (SACS)

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(1)

Published: April 20, 2023

This topical review focuses on the distinct role of carbon support coordination environment single-atom catalysts (SACs) for electrocatalysis. The article begins with an overview atomic configurations in SACs, including a discussion advanced characterization techniques and simulation used understanding active sites. A summary key electrocatalysis applications is then provided. These processes are oxygen reduction reaction (ORR), evolution (OER), hydrogen (HER), nitrogen (NRR), dioxide (CO

Language: Английский

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Atomically precise electrocatalysts for oxygen reduction reaction

Chem, Journal Year: 2023, Volume and Issue: 9(2), P. 280 - 342

Published: Feb. 1, 2023

Language: Английский

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