Integrating Single Atoms with Different Microenvironments into One Porous Organic Polymer for Efficient Photocatalytic CO₂ Reduction

Advanced Materials, Год журнала: 2021, Номер 33(33)

Опубликована: Июль 8, 2021

Abstract The precise identification of single‐atom catalysts (SACs) activity and boosting their efficiency toward CO 2 conversion is imperative yet quite challenging. Herein, for the first time a series porous organic polymers designed prepared simultaneously, containing well‐defined M–N 4 O sites. Such strategy not only offers multiactive sites to promote catalytic but also provides more direct chance identify metal center activity. photoreduction results indicate that introduction salphen unit with Ni–N centers into pristine phthalocyanine‐based framework achieves remarkable generation ability (7.77 mmol g –1 ) high selectivity 96% over H . In combination control experiments, as well theoretical studies, moiety evidenced active site RR compared traditional moiety, which can be ascribed effectively reducing energy barrier, facilitating adsorption reaction radicals *COOH, improving charge transportation. This work might shed some light on designing efficient SACs reduction through modification coordination environments.

Язык: Английский

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Interfacial Reduction Nucleation of Noble Metal Nanodots on Redox-Active Metal–Organic Frameworks for High-Efficiency Electrocatalytic Conversion of Nitrate to Ammonia

Nano Letters, Год журнала: 2022, Номер 22(6), С. 2529 - 2537

Опубликована: Март 10, 2022

Electrochemically converting nitrate to ammonia is a promising route realize artificial nitrogen recycling. However, developing highly efficient electrocatalysts an ongoing challenge. Herein, we report the construction of stable and redox-active zirconium metal-organic frameworks (Zr-MOFs) based on Zr6 nanoclusters redox-reversible tetrathiafulvalene (TTF) derivatives as inorganic nodes organic linkers, respectively. The Zr-MOF can facilitate in situ reduction noble metal precursors free external reductants uniform nucleation nanodots (NDs) Zr-MOF, achieving preparation M-NDs/Zr-MOF (M = Pd, Ag, or Au). porous with good conductivity mass transfer process. Among catalysts, Pd-NDs/Zr-MOF exhibits highest electrocatalytic activity, delivering NH3 yield 287.31 mmol·h-1·g-1cat. Faradaic efficiency 58.1%. proposed interfacial strategy for anchoring M NDs Zr-MOFs be applied other challenging energy conversion reactions.

Язык: Английский

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Porphyrin and phthalocyanine based covalent organic frameworks for electrocatalysis

Coordination Chemistry Reviews, Год журнала: 2022, Номер 464, С. 214563 - 214563

Опубликована: Апрель 22, 2022

Язык: Английский

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Electron Donor–Acceptor Interface of TPPS/PDI Boosting Charge Transfer for Efficient Photocatalytic Hydrogen Evolution

Advanced Science, Год журнала: 2022, Номер 9(17)

Опубликована: Апрель 11, 2022

Charge separation efficiency of photocatalysts is still the key scientific issue for solar-to-chemical energy conversion. In this work, an electron donor-acceptor (D-A) interface with high charge between TPPS (tetra(4-sulfonatophenyl)porphyrin) and PDI (perylene diimide) successfully constructed boosting photocatalytic H

Язык: Английский

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Post-synthetic modification of covalent organic frameworks for CO2 electroreduction

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

Опубликована: Июнь 26, 2023

To achieve high-efficiency catalysts for CO2 reduction reaction, various catalytic metal centres and linker molecules have been assembled into covalent organic frameworks. The amine-linkages enhance the binding ability of molecules, ionic frameworks enable to improve electronic conductivity charge transfer along However, directly synthesis with is hardly achieved due electrostatic repulsion predicament strength linkage. Herein, we demonstrate reaction by modulating linkers linkages template framework build correlation between performance structures Through double modifications, states are well tuned, resulting in controllable activity selectivity reaction. Notably, dual-functional achieves high a maximum CO Faradaic efficiency 97.32% turnover frequencies value 9922.68 h-1, which higher than those base single-modified Moreover, theoretical calculations further reveal that attributed easier formation immediate *CO from COOH*. This study provides insights developing

Язык: Английский

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Imparting CO₂ Electroreduction Auxiliary for Integrated Morphology Tuning and Performance Boosting in a Porphyrin‐based Covalent Organic Framework

Angewandte Chemie International Edition, Год журнала: 2021, Номер 61(5)

Опубликована: Ноя. 22, 2021

Strategies that enable simultaneous morphology-tuning and electroreduction performance boosting are much desired for the exploration of covalent organic frameworks in efficient CO2 electroreduction. Herein, a kind functionalizing exfoliation agent has been selected to simultaneously modify exfoliate bulk COFs into functional nanosheets investigate their performance. The obtained (Cu-Tph-COF-Dct) with large-scale (≈1.0 μm) ultrathin (≈3.8 nm) morphology superior FECH4 (≈80 %) (almost doubly enhanced than bare COF) large current-density (-220.0 mA cm-2 ) at -0.9 V. boosted can be ascribed immobilized (Dct groups) integrated amino triazine groups strengthen absorption/activation, stabilize intermediates enrich CO concentration around Cu active sites as revealed by DFT calculations. point-to-point functionalization strategy modularly assembling Dct-functionalized COF catalyst will open up attractive possibility developing RR electrocatalysts.

Язык: Английский

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Oxygen‐Rich Cobalt–Nitrogen–Carbon Porous Nanosheets for Bifunctional Oxygen Electrocatalysis

Advanced Functional Materials, Год журнала: 2022, Номер 32(23)

Опубликована: Март 4, 2022

Abstract Metal–nitrogen–carbon (M–N–C) materials have attracted much interest in bifunctional oxygen‐involving electrocatalysis for rechargeable Zn–air batteries. Such M–N–C electrocatalysts with M–N x sites show good activity the oxygen reduction reaction (ORR) but moderate evolution (OER). Herein, an oxygen‐rich material (O–Co–N/C) a highly porous nanosheet structure is reported as electrocatalyst, which prepared by direct pyrolysis of ultrathin CoO nanosheets decorated zeolitic imidazolate framework‐8 nanoparticles under inert atmosphere. Particularly, Co O–Co–N/C electrocatalyst contain both Co–N and Co–O coordination environments to provide intrinsic active ORR OER, respectively. Furthermore, electrochemical studies that catalyst retains comparable common half‐wave potential 0.85 V vs reversible hydrogen electrode better OER overpotential 0.29 at current density 10 mA cm −2 . This study provides insights into development effective metal centers coordinated nitrogen atoms.

Язык: Английский

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Ionic Covalent Organic Frameworks for Energy Devices

Advanced Materials, Год журнала: 2021, Номер 33(52)

Опубликована: Окт. 8, 2021

Covalent organic frameworks (COFs) are a class of porous crystalline materials whose facile preparation, functionality, and modularity have led to their becoming powerful platforms for the development molecular devices in many fields (bio)engineering, such as energy storage, environmental remediation, drug delivery, catalysis. In particular, ionic COFs (iCOFs) highly useful constructing devices, functional groups can transport ions efficiently, nonlabile ordered all-covalent pore structures backbones provide ideal pathways long-term under harsh electrochemical conditions. Here, current research progress on use iCOFs specifically lithium-based batteries fuel cells, is reviewed terms iCOF backbone-design strategies, synthetic approaches, properties, engineering techniques, applications. categorized anionic or cationic COFs, how each these types lithium ions, protons, hydroxides illustrated. Finally, challenges future opportunities utilization described. This review will therefore serve reference state-of-the-art design application strategies focusing devices.

Язык: Английский

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Maximizing Electroactive Sites in a Three‐Dimensional Covalent Organic Framework for Significantly Improved Carbon Dioxide Reduction Electrocatalysis

Angewandte Chemie International Edition, Год журнала: 2021, Номер 61(1)

Опубликована: Окт. 30, 2021

Synthesis of functional 3D COFs with irreversible bond is challenging. Herein, imide-bonded were constructed via the imidization reaction between phthalocyanine-based tetraanhydride and 1,3,5,7-tetra(4-aminophenyl)adamantine. These two are made up interpenetrated pts networks according to powder X-ray diffraction gas adsorption analyses. CoPc-PI-COF-3 doped carbon black has been employed fabricate electrocatalytic cathode towards CO2 reduction within KHCO3 aqueous solution, displaying Faradaic efficiency 88-96 % for -to-CO conversion at voltage range ca. -0.60 -1.00 V (vs. RHE). In particular, porous structure enables active centers occupying 32.7 total cobalt-phthalocyanine subunits, thus giving a large current density (jCO ) -31.7 mA cm-2 -0.90 V. parameters significantly improved than excellent 2D COF analogue (CoPc-PI-COF-1, 5.1 -21.2 ).

Язык: Английский

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Controlling Oxygen Reduction Selectivity through Steric Effects: Electrocatalytic Two‐Electron and Four‐Electron Oxygen Reduction with Cobalt Porphyrin Atropisomers

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(23), С. 12742 - 12746

Опубликована: Март 20, 2021

Abstract Achieving a selective 2 e − or 4 oxygen reduction reaction (ORR) is critical but challenging. Herein, we report controlling ORR selectivity of Co porphyrins by tuning only steric effects. We designed porphyrin 1 with meso ‐phenyls each bearing bulky ortho ‐amido group. Due to the resulted hinderance, has four atropisomers similar electronic structures dissimilar Isomers αβαβ and αααα catalyze n =2.10 3.75 ( electron number transferred per O ), respectively, ααββ αααβ show poor =2.89–3.10. Isomer catalyzes preventing bimolecular activation path, while improves improving binding at its pocket, feature confirmed spectroscopy methods, including K‐edge near‐edge X‐ray absorption fine structure. This work represents an unparalleled example improve effects without changing molecular structures.

Язык: Английский

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