Simultaneously Engineering the Synergistic-Effects and Coordination-Environment of Dual-Single-Atomic Iron/Cobalt-sites as a Bifunctional Oxygen Electrocatalyst for Rechargeable Zinc-Air Batteries

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(4), P. 2313 - 2325

Published: Jan. 30, 2023

Single-atom introduced carbon nanomaterials show favorable oxygen-reduction reaction (ORR) and oxygen-evolution (OER) performance for renewable energy applications. Nevertheless, the electronic-structure regulation by decorating heterogeneous single-metal-atoms engineering of a single-atom active-sites' microenvironment need to be optimized simultaneously, which is challenging. Herein, we develop an atomic-interfacial-regulation approach fabricate dual single Fe/Co atoms synchronized with both nitrogen/sulfur on defective/graphitic/porous nanosheets (Fe,Co/DSA-NSC). The unsymmetrically organized N S coordinated bridged atomic-sites [Fe-(N2S)/Co-(N2S) moiety] are established prompt charge-transfer, lowering barrier oxygenated reaction-intermediates leading boost reaction-kinetics. As estimated, Fe,Co/DSA-NSC exhibits improved ORR/OER activity higher half-wave potential lower overpotential (E1/2 = 879 mV η10 210 mV, respectively) also good cycling stability toward zinc-air batteries. This discovery hence provides widespread scheme synergistic-principles dual-single-atom catalysts controlled

Language: Английский

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Breaking the Scaling Relationship Limit: From Single-Atom to Dual-Atom Catalysts

Accounts of Materials Research, Journal Year: 2022, Volume and Issue: 3(6), P. 584 - 596

Published: May 17, 2022

ConspectusRecent decades have witnessed the rapid development of catalytic science, especially after Taylor and Armstrong proposed notion "active site" in 1925. By optimizing reaction paths reducing activation energies reactions, catalysts appear more than 90% chemical production involving homogeneous catalysis, heterogeneous enzyme catalysis. Because 100% efficiency active atom utilization adjustable microenvironment metal centers, single-atom (SACs) shine various fields for enhancing rate, conversion, selectivity reactions. Nevertheless, a solo site determines fixed adsorption mode, intermediates from multistep reactions linking with are related to each other. For specific reaction, it is almost impossible optimally adjust every intermediate on simultaneously. This phenomenon termed scaling relationship limit (SRL) an unavoidable obstacle pure SACs.Dual-atom (DACs), perfectly inheriting advantages SACs, can exhibit better performance simple SACs thus gradually gained researchers' attention. Depending dual-metal structure, sites (DMSs) DACs be divided into two separated heterometal sites, linked homometal sites. Two prescribe distance between electron interaction. Currently, origins summarized following three points: (1) electronic effect, which only one center serves as other plays regulatory role; (2) synergistic centers separately catalyze different core steps improve together; (3) offering additional changes structures break SRL based SACs. Among origins, structure upon DMSs most effective technologies boost property basis To date, few contributions focused catalysis environments, including O2 reduction evolution H2 CO2 N2 conversion reactions.In this Account, summary recent progress regarding will presented. First, unpopular discovery research hot spot illustrated through timeline. In next section, categories, potential revealed by comparison addition, techniques constructing systematically summarized, preparation carbonous, pyrolysis-free, noncarbon-supported, complex-type DACs. Furthermore, underlying energy- environment-related introduced detail assistance theoretical calculations. Finally, we affirm contribution particularly electrocatalysis, provide outlook direction discussing major challenges. It anticipated that Account inspire researchers propel advance

Language: Английский

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Tailoring the d‐Orbital Splitting Manner of Single Atomic Sites for Enhanced Oxygen Reduction

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(14)

Published: Feb. 11, 2023

Regulating the electronic states of single atomic sites around Fermi level remains a major concern for boosting electrocatalytic oxygen reduction reaction (ORR). Herein, Fe d-orbital splitting manner modulation strategy by constructing axial coordination on FeN4 is presented. Experimental investigations and theoretical calculations reveal that tractions induce distortion square-planar field (FeN4 SP), up to quasi-octahedral O1 OCquasi ), thus leading electron rearrangement with diluted spin polarization. The declined population unpaired electrons in dz2 , dxz dyz engenders moderate adsorption ORR intermediates, thereby reinforcing intrinsic activity. In situ infrared spectroscopy further demonstrates reordering occupation facilitates desorption *OH. exhibits dramatic improvement kinetic current density turnover frequency, which are fivefold tenfold higher than those SP. This work presents novel understanding improving performance through orbital-scale manipulation.

Language: Английский

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Recent advances in electrocatalytic oxygen reduction for on-site hydrogen peroxide synthesis in acidic media

Journal of Energy Chemistry, Journal Year: 2021, Volume and Issue: 67, P. 432 - 450

Published: Oct. 28, 2021

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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Heteroatom‐Driven Coordination Fields Altering Single Cerium Atom Sites for Efficient Oxygen Reduction Reaction

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(28)

Published: April 4, 2023

For current single-atom catalysts (SACs), modulating the coordination environments of rare-earth (RE) single atoms with complex electronic orbital and flexible chemical states is still limited. Herein, cerium (Ce) SAs supported on a P, S, N co-doped hollow carbon substrate (Ce SAs/PSNC) for oxygen reduction reaction (ORR) are reported. The as-prepared Ce SAs/PSNC possesses half-wave potential 0.90 V, turnover frequency value 52.2 s

Language: Английский

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Optimizing Microenvironment of Asymmetric N,S‐Coordinated Single‐Atom Fe via Axial Fifth Coordination toward Efficient Oxygen Electroreduction

Small, Journal Year: 2021, Volume and Issue: 18(2)

Published: Nov. 20, 2021

Single-atom catalysts (SACs) are attractive candidates for oxygen reduction reaction (ORR). The catalytic performances of SACs mainly determined by the surrounding microenvironment single metal sites. Microenvironment engineering and understanding structure-activity relationship is critical, which remains challenging. Herein, a self-sacrificing strategy developed to synthesize asymmetric N,S-coordinated single-atom Fe with axial fifth hydroxy (OH) coordination (Fe-N3 S1 OH) embedded in N,S codoped porous carbon nanospheres (FeN/SC). Such unique penta-coordination cutting-edge techonologies aiding systematic simulations. as-obtained FeN/SC exhibits superior ORR activity, showcases half-wave potential 0.882 V surpassing benchmark Pt/C. Moreover, theoretical calculations confirmed OH FeN3 can optimize 3d orbitals center strengthen O2 adsorption enhance activation on site, thus reducing barrier accelerating dynamics. Furthermore, containing H2 O2 fuel cell performs high peak power density 512 mW cm-2 , based Znair batteries show 203 49 liquid flexible all-solid-state configurations, respectively. This study offers new platform fundamentally understand asymmetrical planar sites electrocatalysis.

Language: Английский

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Simultaneously Integrate Iron Single Atom and Nanocluster Triggered Tandem Effect for Boosting Oxygen Electroreduction

Small, Journal Year: 2022, Volume and Issue: 18(15)

Published: Feb. 26, 2022

Abstract Atomically nitrogen‐coordinated iron atoms on carbon (FeNC) catalysts are emerging as attractive materials to substitute precious‐metal‐based for the oxygen reduction reaction (ORR). However, FeNC usually suffers from unsatisfactory performance due symmetrical charge distribution around site. Elaborately regulating microenvironment of central Fe atom can substantially improve catalytic activity FeNC, which remains challenging. Herein, N/S co‐doped porous carbons rationally prepared and verified with rich Fe‐active sites, including atomically dispersed FeN 4 nanoclusters (FeSA‐FeNC@NSC), according systematically synchrotron X‐ray absorption spectroscopy analysis. Theoretical calculation verifies that contiguous S break symmetric electronic structure synergistically optimize 3 d orbitals centers, thus accelerating OO bond cleavage in OOH* improving ORR activity. The FeSA‐Fe NC @NSC delivers an impressive half‐wave‐potential 0.90 V, exceeds state‐of‐the‐art Pt/C (0.87 V). Furthermore, @NSC‐based Zn‐air batteries deliver excellent power densities 259.88 55.86 mW cm –2 liquid all‐solid‐state flexible configurations, respectively. This work presents effective strategy modulate single atomic centers boost single‐atom by tandem effect.

Language: Английский

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Carbon Nanocage with Maximum Utilization of Atomically Dispersed Iron as Efficient Oxygen Electroreduction Nanoreactor

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(5)

Published: Nov. 9, 2022

As key parameters of electrocatalysts, the density and utilization active sites determine electrocatalytic performance toward oxygen reduction reaction. Unfortunately, prevalent electrocatalysts fail to maximize due inappropriate nanostructural design. Herein, a nano-emulsion induced polymerization self-assembly strategy is employed prepare hierarchical meso-/microporous N/S co-doped carbon nanocage with atomically dispersed FeN4 (denoted as Meso/Micro-FeNSC). In situ scanning electrochemical microscopy technology reveals available for Meso/Micro-FeNSC reach 3.57 × 1014 cm-2 , representing more than threefold improvement compared micropore-dominant Micro-FeNSC counterpart (1.07 ). Additionally, turnover frequency also improved 0.69 from 0.50 e- site-1 s-1 Micro-FeNSC. These properties motivate efficient electroreduction electrocatalyst, in terms outstanding half-wave potential (0.91 V), remarkable kinetic mass specific activity (68.65 A g-1 ), excellent robustness. The assembled Zn-air batteries deliver high peak power (264.34 mW large capacity (814.09 mA h long cycle life (>200 h). This work sheds lights on quantifying site significance maximum rational design advanced catalysts.

Language: Английский

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Structural optimization of carbon-based diatomic catalysts towards advanced electrocatalysis

Coordination Chemistry Reviews, Journal Year: 2023, Volume and Issue: 492, P. 215288 - 215288

Published: June 12, 2023

Language: Английский

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