Dithiine-linked metalphthalocyanine framework with undulated layers for highly efficient and stable H2O2 electroproduction

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Янв. 23, 2024

Realization of stable and industrial-level H

Язык: Английский

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Optimization Strategies of Covalent Organic Frameworks and Their Derivatives for Electrocatalytic Applications

Advanced Functional Materials, Год журнала: 2023, Номер 34(11)

Опубликована: Ноя. 27, 2023

Abstract Covalent organic frameworks (COFs) are crystalline porous polymers that can be precisely integrated by building blocks to achieve pre‐designed composition, components, and functions, making them a powerful platform for the development of molecular devices in field electrocatalysis. The precise control channel/dopant positions highly ordered network structures COFs provide an ideal material system applications advanced In this paper, topological structure design synthesis methods reviewed detail, their principles deeply analyzed. addition, derivatives electrocatalysis systematically summarized optimization strategies proposed. Finally, application prospects challenges may encountered future prospected, providing helpful guidance research.

Язык: Английский

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Catalytic Linkage Engineering of Covalent Organic Frameworks for the Oxygen Reduction Reaction

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(30)

Опубликована: Апрель 28, 2023

Metal-free covalent organic frameworks (COFs) have been employed to catalyze the oxygen reduction reaction (ORR). To achieve high activity and selectivity, various building blocks containing heteroatoms groups linked by imine bonds were used create catalytic COFs. However, roles of linkages COFs in ORR not investigated. In this work, linkage engineering has modulate behaviors. single sites while avoiding other possible sites, we synthesized from benzene units bonds, such as imine, amide, azine, oxazole bonds. Among these COFs, oxazole-linkage enables with highest activity, which achieved a half-wave potential 0.75 V limited current density 5.5 mA cm-2 . Moreover, oxazole-linked COF conversion frequency (TOF) value 0.0133 S-1 , 1.9, 1.3, 7.4-times that azine-, amide- imine-COFs, respectively. The theoretical calculation showed carbon atoms facilitated formation OOH* promoted protonation O* form OH*, thus advancing activity. This work guides us on are suitable for ORR.

Язык: Английский

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Single-atom platinum with asymmetric coordination environment on fully conjugated covalent organic framework for efficient electrocatalysis

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Март 22, 2024

Abstract Two-dimensional (2D) covalent organic frameworks (COFs) and their derivatives have been widely applied as electrocatalysts owing to unique nanoscale pore configurations, stable periodic structures, abundant coordination sites high surface area. This work aims construct a non-thermodynamically Pt-N 2 active site by electrochemically modifying platinum (Pt) single atoms into fully conjugated 2D COF conductive agent-free pyrolysis-free electrocatalyst for the hydrogen evolution reaction (HER). In addition maximizing atomic utilization, single-atom catalysts with definite structures can be used investigate catalytic mechanisms structure-activity relationships. this work, in-situ characterizations theoretical calculations reveal that nitrogen-rich graphene analogue not only exhibits favorable metal-support effect Pt, adjusting binding energy between Pt H* intermediates forming instead of typical 4 environment, but also enhances electron transport ability structural stability, showing both conductivity stability in acidic environments.

Язык: Английский

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Engineering organic polymers as emerging sustainable materials for powerful electrocatalysts

Chemical Society Reviews, Год журнала: 2024, Номер 53(3), С. 1447 - 1494

Опубликована: Янв. 1, 2024

A comprehensive overview on organic polymers as electrocatalysts is summarized. By presenting the engineering strategies, insightful understandings, challenges, and perspectives, we hope this review can provide valuable references for readers.

Язык: Английский

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Charging modulation of the pyridine nitrogen of covalent organic frameworks for promoting oxygen reduction reaction

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Фев. 29, 2024

Abstract Covalent organic frameworks (COFs) are ideal templates for constructing metal-free catalysts the oxygen reduction reaction due to their highly tuneable skeletons and controllable porous channels. However, development of active sites within COFs remains challenging limited electron-transfer capabilities weak binding affinities intermediates. Herein, we constructed catalytic centres by modulating electronic states pyridine nitrogen atoms incorporated into COFs. By incorporating different units (such as pyridine, ionic imidazole units), tuned various properties including dipole moments, reductive ability, hydrophilicity, towards Notably, COF ( im -PY-BPY-COF) exhibited greater activity than neutral (PY-BPY-COF) ion -PY-BPY-COF). Specifically, -PY-BPY-COF demonstrated a half-wave potential 0.80 V in 0.1 M KOH, outperforming other Theoretical calculations situ synchrotron radiation Fourier transform infrared spectroscopy confirmed that carbon rings improved facilitating intermediate OOH* promoting desorption OH*. This study provides new insights design metal-like catalysts.

Язык: Английский

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Positional Thiophene Isomerization: A Geometric Strategy for Precisely Regulating the Electronic State of Covalent Organic Frameworks to Boost Oxygen Reduction

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(15)

Опубликована: Фев. 13, 2024

Abstract With the oxygen conversion efficiency of metal‐free carbon‐based fuel cells dramatically improved, building blocks covalent organic frameworks (COFs) raised principal concerns on catalytic active sites with indistinct electronic states. Herein, to address this issue, we demonstrate COFs for reduction reaction (ORR) by regulating edge‐hanging thiophene units, and molecular geometries are further modulated via positional isomerization strategy, affording isomeric COF‐α 2‐substitution COF‐β 3‐substitution frameworks. The states intermediate adsorption ability well‐regulated through geometric modification, resulting in controllable chemical activity local density π‐electrons. Notably, introduction units different substitution positions into a pristine pure COF model COF‐Ph achieves excellent half‐wave potential 0.76 V versus reversible hydrogen electrode, which is higher than most those or metal‐based electrocatalysts. Utilizing combination theoretical prediction situ Raman spectra, show that skeleton ( ) can induce dangling unit activation, accurately identifying pentacyclic‐carbon (thiophene α‐position) adjacent sulfur atom as sites. results suggest groups suitable ORR promising geometry construction.

Язык: Английский

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Molecular Engineering for Modulating Photocatalytic Hydrogen Evolution of Fully Conjugated 3D Covalent Organic Frameworks

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(25)

Опубликована: Апрель 16, 2024

Covalent organic frameworks (COFs) have recently shown great potential for photocatalytic hydrogen production. Currently almost all reports are focused on two-dimensional (2D) COFs, while the 3D counterparts rarely explored due to their non-conjugated derived from sp

Язык: Английский

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Zipper‐Like Interlocked Heterostructure of NiFe Layered Double Hydroxide‐WN for Super‐Stable Oxygen Evolution over 4500 h

Advanced Functional Materials, Год журнала: 2024, Номер unknown

Опубликована: Июль 22, 2024

Abstract The nickel‐iron based materials are widely studied as excellent oxygen evolution reaction (OER) electrocatalysts. However, its relatively poor OER stability limits practical applications. Herein, a zipper‐like interlocked heterostructure of NiFe layered double hydroxide (LDH)‐WN is constructed. LDH‐WN exhibits not only ultrahigh activity 228 mV overpotential at current density 50 mA cm −2 , but also extremely long‐term over 4500 h and 550 an industrial ≈350 which ascribed to special structure. Moreover, in situ Raman confirms that the presence WN can efficiently achieve LDH reconstruction slower metal dissolution during OER, therefore boosts stability. DFT calculations reveal increase *O adsorption capability conductivity layer, anchor atoms layer improve energy barrier. In short, this work presents new method constructing Ni‐Fe‐based catalysts, would accelerate application.

Язык: Английский

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Multicomponent Synthesis of Imidazole‐Linked Fully Conjugated 3D Covalent Organic Framework for Efficient Electrochemical Hydrogen Peroxide Production

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(49)

Опубликована: Окт. 26, 2023

The semiconducting properties and applications of three dimensional (3D) covalent organic frameworks (COFs) are greatly hampered because their long-ranged non-conjugated skeletons relatively unstable linkages. Here, a robust imidazole-linked fully conjugated 3D framework (BUCT-COF-7) is synthesized through the one-pot multicomponent Debus-Radziszewski reaction saddle-shaped aldehyde-substituted cyclooctatetrathiophene, pyrene-4,5,9,10-tetraone, ammonium acetate. BUCT-COF-7, as metal-free catalyst, shows excellent two electron oxygen reduction (ORR) activity in alkaline medium with high hydrogen peroxide (H2 O2 ) selectivity 83.4 %. When BUCT-COF-7 cathode catalyst assembled into electrolyzer, devices showed electrochemical production rate H2 up to 326.9 mmol g-1 h-1 . accumulative amount could totally degrade dye methylene blue via Fenton for wastewater treatment. This first report about intrinsic COFs efficient synthesis , revealing promising environment-related field.

Язык: Английский

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