Understanding the structure-performance relationship of active sites at atomic scale

Nano Research, Год журнала: 2022, Номер 15(8), С. 6888 - 6923

Опубликована: Июнь 14, 2022

Язык: Английский

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Tuning Two‐Electron Oxygen‐Reduction Pathways for H₂O₂ Electrosynthesis via Engineering Atomically Dispersed Single Metal Site Catalysts

Advanced Materials, Год журнала: 2022, Номер 34(23)

Опубликована: Фев. 8, 2022

Abstract The hydrogen peroxide (H 2 O ) generation via the electrochemical oxygen reduction reaction (ORR) under ambient conditions is emerging as an alternative and green strategy to traditional energy‐intensive anthraquinone process unsafe direct synthesis using H . It enables on‐site decentralized production air renewable electricity for various applications. Currently, atomically dispersed single metal site catalysts have emerged most promising platinum group (PGM)‐free electrocatalysts ORR. Further tuning their central sites, coordination environments, local structures can be highly active selective 2e − Herein, recent methodologies achievements on developing are summarized. Combined with theoretical computation advanced characterization, a structure–property correlation guide rational catalyst design favorable ORR aimed provide. Due oxidative nature of derived free radicals, stability effective solutions improve tolerance emphasized. Transferring intrinsic properties electrode performance viable applications always remains grand challenge. key metrics knowledge during electrolyzer development are, therefore, highlighted.

Язык: Английский

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Edge‐hosted Atomic Co−N₄Sites on Hierarchical Porous Carbon for Highly Selective Two‐electron Oxygen Reduction Reaction

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(51)

Опубликована: Окт. 25, 2022

Not only high efficiency but also selectivity of the electrocatalysts is crucial for high-performance, low-cost, and sustainable energy storage applications. Herein, we systematically investigate edge effect carbon-supported single-atom catalysts (SACs) on oxygen reduction reaction (ORR) pathways (two-electron (2 e- ) or four-electron (4 )) conclude that 2 -ORR proceeding over edge-hosted atomic Co-N4 sites more favorable than basal-plane-hosted ones. As such, have successfully synthesized tuned Co-SACs with different edge-to-bulk ratios. The as-prepared edge-rich Co-N/HPC catalyst exhibits excellent performance a remarkable ≈95 % in wide potential range. Furthermore, find functional groups could saturate graphitic carbon edges under ORR operation further promote electrocatalytic performance. These findings structure-property relationship SACs offer promising direction large-scale low-cost electrochemical H2 O2 production via -ORR.

Язык: Английский

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Sb2S3-templated synthesis of sulfur-doped Sb-N-C with hierarchical architecture and high metal loading for H2O2 electrosynthesis

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Янв. 23, 2023

Abstract Selective two-electron (2e − ) oxygen reduction reaction (ORR) offers great opportunities for hydrogen peroxide (H 2 O electrosynthesis and its widespread employment depends on identifying cost-effective catalysts with high activity selectivity. Main-group metal nitrogen coordinated carbons (M-N-Cs) are promising but remain largely underexplored due to the low metal-atom density lack of understanding in structure-property correlation. Here, we report using a nanoarchitectured Sb S 3 template synthesize high-density (10.32 wt%) antimony (Sb) single atoms nitrogen- sulfur-codoped carbon nanofibers (Sb-NSCF), which exhibits both selectivity (97.2%) mass (114.9 A g −1 at 0.65 V) toward 2e ORR alkaline electrolyte. Further, when evaluated practical flow cell, Sb-NSCF shows production rate 7.46 mol catalyst h negligible loss 75-h continuous electrolysis. Density functional theory calculations demonstrate that coordination configuration dopants synergistically contribute enhanced Sb-N 4 moieties.

Язык: Английский

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Continuous electroproduction of formate via CO2 reduction on local symmetry-broken single-atom catalysts

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Окт. 27, 2023

Abstract Atomic-level coordination engineering is an efficient strategy for tuning the catalytic performance of single-atom catalysts (SACs). However, their rational design has so far been plagued by lack a universal correlation between symmetry and properties. Herein, we synthesised planar-symmetry-broken CuN 3 (PSB-CuN ) SACs through microwave heating electrocatalytic CO 2 reduction. Remarkably, as-prepared exhibited selectivity 94.3% towards formate at −0.73 V vs. RHE, surpassing symmetrical 4 catalyst (72.4% −0.93 RHE). In flow cell equipped with PSB-CuN electrode, over 90% was maintained average current density 94.4 mA cm −2 during 100 h operation. By combining definitive structural identification operando X-ray spectroscopy theoretical calculations, revealed that intrinsic local breaking from planar D configuration induces unconventional dsp hybridisation, thus strong activity microenvironment metal centre (i.e., number distortion), high preference production in moiety. The finding opens avenue designing specific symmetries selective electrocatalysis.

Язык: Английский

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Versatile Photoelectrocatalysis Strategy Raising Up the Green Production of Hydrogen Peroxide

Advanced Energy Materials, Год журнала: 2023, Номер 13(14)

Опубликована: Март 1, 2023

Abstract H 2 O plays an irreplaceable role in many aspects of human society, such as paper bleaching, medical disinfection, wastewater treatment, organic synthesis, hydrometallurgy and the electronic industry. However, unsustainability current industrial production process traditional anthraquinone has a serious conflict with green sustainable development. The photo/electrocatalytic from renewable energy advantages being more economical, low‐carbon green, line requirements economy. These catalytic methods have played demonstrative development small molecules, contributing to fundamental understanding general catalysis providing scientific perspective for future new cycles. In this review, authors aim integrate reaction mechanism photocatalytic electrocatalytic production, summarize application recent years, assess modern technologies promoted research, including flux equipment coproduction, etc. This review intends provide clear logic profile directions calls researchers insights into field.

Язык: Английский

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Low-coordinated Co-N3 sites induce peroxymonosulfate activation for norfloxacin degradation via high-valent cobalt-oxo species and electron transfer

Journal of Hazardous Materials, Год журнала: 2023, Номер 455, С. 131622 - 131622

Опубликована: Май 11, 2023

Язык: Английский

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Super‐Coordinated Nickel N₄Ni₁O₂Site Single‐Atom Catalyst for Selective H₂O₂Electrosynthesis at High Current Densities

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(38)

Опубликована: Авг. 2, 2022

Electrochemical production of hydrogen peroxide (H2 O2 ) from on single-atom catalysts has attracted great attention, yet the quest for robust is driven by achieving >90 % Faradaic efficiency (FE) under industrial-relevant current densities (>100 mA cm-2 ). Herein we synthesize a catalyst that contains single nickel site coordinated four nitrogen and two oxygen atoms (i.e., N4 Ni1 via involving carboxyl functionalized multiwall carbon nanotubes as substrate to provide extra O coordination regular NiN4 site. It cathodic energy approximately 82 H2 FE around 96 at 200 density, outperforming reported electrosynthesis.

Язык: Английский

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Photocatalytic and Electrocatalytic Generation of Hydrogen Peroxide: Principles, Catalyst Design and Performance

Nano-Micro Letters, Год журнала: 2023, Номер 15(1)

Опубликована: Март 28, 2023

Hydrogen peroxide (H2O2) is a high-demand organic chemical reagent and has been widely used in various modern industrial applications. Currently, the prominent method for preparation of H2O2 anthraquinone oxidation. Unfortunately, it not conducive to economic sustainable development since complex process involves unfriendly environment potential hazards. In this context, numerous approaches have developed synthesize H2O2. Among them, photo/electro-catalytic ones are considered as two most promising manners on-site synthesis These alternatives that only water or O2 required. Namely, oxidation (WOR) oxygen reduction (ORR) reactions can be further coupled with clean energy. For generation, design catalysts extremely important extensively conducted an aim obtain ultimate catalytic performance. This article overviews basic principles WOR ORR, followed by summary recent progresses achievements on performance photo/electro-catalysts generation. The related mechanisms these highlighted from theoretical experimental aspects. Scientific challenges opportunities engineering generation also outlined discussed.

Язык: Английский

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Single-atom CoN4 sites with elongated bonding induced by phosphorus doping for efficient H2O2 electrosynthesis

Applied Catalysis B Environment and Energy, Год журнала: 2022, Номер 324, С. 122267 - 122267

Опубликована: Дек. 5, 2022

Язык: Английский

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