Stabilizing High Density Cu Active Sites with ZrO2 Quantum Dots as Chemical Ligand in N‐doped Porous Carbon Nanofibers for Efficient ORR DOI
Yue Qiao, Yuanyuan Zhang,

Shuhui Xia

et al.

Small, Journal Year: 2023, Volume and Issue: 19(15)

Published: Jan. 11, 2023

The emerging transition metal-nitrogen-carbon (MNC) materials are considered as a promising oxygen reduction reaction (ORR) catalyst system to substitute expensive Pt/C catalysts due their high surface area and potential catalytic activity. However, MNC easy be attacked by the ORR byproducts that easily lead deactivation of metal active sites. Moreover, loading affects mass transfer stability, but low delivers inferior Here, new strategy designing ZrO2 quantum dots N-complex dual chemical ligands in N-doped bubble-like porous carbon nanofibers (N-BPCNFs) stabilize copper (Cu) forming CuZrO3-x /ZrO2 heterostructures CuN with 40.5 wt.% is reported. While highly architecture design N-BPCNFs builds large solidelectrolytegas phase interface promotes transfer. preliminary results show half-wave reaches 0.856 V, only decreases 0.026 V after 10 000 cycles, exhibiting excellent stability. proposed stabilizing sites both feasible scalable for developing catalyst.

Language: Английский

Breaking the N-limitation with N-enriched porous submicron carbon spheres anchored Fe single-atom catalyst for superior oxygen reduction reaction and Zn-air batteries DOI
Mengxia Shen, Jun Liu, Ji Li

et al.

Energy storage materials, Journal Year: 2023, Volume and Issue: 59, P. 102790 - 102790

Published: April 23, 2023

Language: Английский

Citations

52
An in situ exploration of how Fe/N/C oxygen reduction catalysts evolve during synthesis under pyrolytic conditions DOI Creative Commons

Shuhu Yin,

H. Yi, Mengli Liu

et al.

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: July 24, 2024

Abstract In pursuing cheap and effective oxygen reduction catalysts, the Fe/N/C system emerges as a promising candidate. Nevertheless, structural transformations of starting materials into Fe- N-doped carbon catalysts remains poorly characterized under pyrolytic conditions. Here, we explore evolution Fe species track formation Fe–N 4 site development by employing diverse in-situ diagnostic techniques. In-situ heating microscopy reveals initial FeO x nanoparticles subsequent internal migration within matrix, which stops once is fully reduced. The decomposition then leads to layer reconstruction. Experimental theoretical analysis size-dependent behavior where below 7 nm readily release atoms form while with sizes >10 tend coalesce impede formation. work visualizes pyrolysis process materials, providing guidance for rational design catalysts.

Language: Английский

Citations

24
One‐Pot Etching Pyrolysis to Defect‐Rich Carbon Nanosheets to Construct Multiheteroatom‐Coordinated Iron Sites for Efficient Oxygen Reduction DOI
Shichao Peng,

Xilan Ma,

Jiachen Tian

et al.

Small, Journal Year: 2024, Volume and Issue: 20(33)

Published: April 9, 2024

Constructing multiheteroatom coordination structure in carbonaceous substrates demonstrates an effective method to accelerate the oxygen reduction reaction (ORR) of supported single-atom catalyst. Herein, novel etching route assisted by potassium thiocyanate (KCNS) is developed convert metal-organic framework 2D defect-rich porous N,S-co-doped carbon nanosheets for anchoring atomically dispersed iron sites as high-performance ORR catalysts (Fe-SACs). The well-designed KCNS-assisted can generate spatial confinement template direct nanosheet formation, condition form structure, and additional sulfur atoms coordinate species. Spectral microscopy analysis reveals that element Fe-SACs highly isolated on anchored nitrogen unsymmetrical Fe-S

Language: Английский

Citations

23
p-d Orbital Hybridization Induced by Asymmetrical FeSn Dual Atom Sites Promotes the Oxygen Reduction Reaction DOI
Xiaochen Wang,

Ning Zhang,

Shuohai Guo

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(31), P. 21357 - 21366

Published: July 25, 2024

With more flexible active sites and intermetal interaction, dual-atom catalysts (DACs) have emerged as a new frontier in various electrocatalytic reactions. Constructing typical p-d orbital hybridization between p-block d-block metal atoms may bring avenues for manipulating the electronic properties thus boosting activities. Herein, we report distinctive heteronuclear dual-metal atom catalyst with asymmetrical FeSn dual embedded on two-dimensional C2N nanosheet (FeSn–C2N), which displays excellent oxygen reduction reaction (ORR) performance half-wave potential of 0.914 V an alkaline electrolyte. Theoretical calculations further unveil powerful stannum ferrum sites, triggers electron delocalization lowers energy barrier *OH protonation, consequently enhancing ORR activity. In addition, FeSn–C2N-based Zn–air battery provides high maximum power density (265.5 mW cm–2) specific capacity (754.6 mA h g–1). Consequently, this work validates immense along perception into logical design DACs.

Language: Английский

Citations

23
Sulfur‐Tuned Main‐Group Sb−N−C Catalysts for Selective 2‐Electron and 4‐Electron Oxygen Reduction DOI

Minmin Yan,

Hao Yang, Zhichao Gong

et al.

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(27)

Published: April 15, 2024

The selective oxygen reduction reaction (ORR) is important for various energy conversion processes such as the fuel cells and metal-air batteries 4e

Language: Английский

Citations

21
Regulating Reactive Oxygen Intermediates of Fe−N−C SAzyme via Second‐Shell Coordination for Selective Aerobic Oxidation Reactions DOI

Yuan Xu,

Yuanjie Ma,

Xinghua Chen

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(36)

Published: June 19, 2024

Reactive oxygen species (ROS) regulation for single-atom nanozymes (SAzymes), e.g., Fe-N-C, is a key scientific issue that determines the activity, selectivity, and stability of aerobic reaction. However, poor understanding ROS formation mechanism on SAzymes greatly hampers their wider deployment. Herein, inspired by cytochromes P450 affording bound intermediates in O

Language: Английский

Citations

18
Electrochemical Probing the Site Reactivity in Iron Single-Atom Catalysts for Electrocatalytic Nitrate Reduction to Ammonia DOI
Hongmei Li, Panpan Li, Yong Guo

et al.

Analytical Chemistry, Journal Year: 2024, Volume and Issue: 96(3), P. 997 - 1002

Published: Jan. 4, 2024

Single-atom catalysts (SACs), specifically iron single atoms dispersed on nitrogen-doped carbon (Fe-NC), have shown promising potential in the electrocatalytic reduction of nitrate to ammonia (NitRR), but there is a lack understanding their intrinsic activity. The conventional measurements often overlook performance SACs, leading significant underestimation. This study presents an situ electrochemical probing protocol, using two poisoning molecules (SCN– and NO2–), characterize reactivity Fe sites Fe-NC SACs for NitRR. technique aids quantifying yield rate active site number. findings reveal turnover frequency (TOF) based number sites, challenging current SACs' inherent performances. unique approach holds considerable determining activity other complex reactions, opening new avenues exploration processes.

Language: Английский

Citations

17
Unveiling Low Temperature Assembly of Dense Fe‐N4 Active Sites via Hydrogenation in Advanced Oxygen Reduction Catalysts DOI

Shuhu Yin,

Yanrong Li,

Jian Yang

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(23)

Published: April 3, 2024

The single-atom Fe-N-C is a prominent material with exceptional reactivity in areas of sustainable energy and catalysis research. It challenging to obtain the dense Fe-N

Language: Английский

Citations

16
Nanomagnetic tetraaza (N4 donor) macrocyclic Schiff base complex of copper(ii): synthesis, characterizations, and its catalytic application in Click reactions DOI Creative Commons
Masoomeh Norouzi,

Nasim Noormoradi,

Masoud Mohammadi

et al.

Nanoscale Advances, Journal Year: 2023, Volume and Issue: 5(23), P. 6594 - 6605

Published: Jan. 1, 2023

In this research, a novel nanomagnetic tetra-azamacrocyclic Schiff base complex of copper(ii) was produced via post-synthetic surface modification an Fe3O4 by silane-coupling agent that contains acetylacetone functionalities at the end its chain. Moreover, target Cu involves tetradentate ligand obtained from template reaction with o-phenylenediamine and Cu(NO3)2·3H2O. Furthermore, prepared nominated as [Fe3O4@TAM-Schiff-base-Cu(II)]. The Fourier-transform infrared (FT-IR) analysis indicates presence Schiff-base-Cu in catalyst. X-ray spectroscopy (EDS) TGA reveal approximately 6-7% catalyst comprises hydrocarbon moieties. scanning electron microscope (SEM) transmission microscopy (TEM) images demonstrate uniformly shaped particles, nearly spherical nature, sizes ranging 9 to 18 nm. [Fe3O4@TAM-Schiff-base-Cu(II)] applied for click synthesis diverse range 5-substituted-1H-tetrazoles PEG-400 green medium. Regarding electrical properties Cu(ii) complex, tetra-aza (N4 donor) macrocyclic N-rich reasonable - leading excellent capacity catalyze these organic transformations. Finally, high magnetization value (44.92 emu g-1) enables recycling least four times without compromising catalytic efficiency.

Language: Английский

Citations

36
Insight into Iron Leaching from an Ascorbate‐Oxidase‐like Fe−N−C Nanozyme and Oxygen Reduction Selectivity** DOI
Xuwen Cao,

Caixia Zhu,

Qing Hong

et al.

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(27)

Published: May 5, 2023

Ascorbate (H2 A) is a well-known antioxidant to protect cellular components from free radical damage and has also emerged as pro-oxidant in cancer therapies. However, such "contradictory" mechanisms underlying H2 A oxidation are not well understood. Herein, we report Fe leaching during catalytic using an Fe-N-C nanozyme ferritin mimic its influence on the selectivity of oxygen reduction reaction (ORR). Owing heterogeneity, Fe-Nx sites primarily catalyzed 4 e- ORR via iron-oxo intermediate. Nonetheless, trace O2 ⋅- produced by marginal N-C through 2 accumulated attacked sites, leading linear leakage unstable ions up 420 ppb when concentration increased mM. As result, substantial fraction (ca. 40 %) were activated, new 2+2 path was finally enabled, along with Fenton-type oxidation. Consequently, after diffused into bulk solution, at stopped production, which origin effect A.

Language: Английский

Citations

32