Dual‐Metal Atom Electrocatalysts: Theory, Synthesis, Characterization, and Applications

Advanced Energy Materials, Год журнала: 2021, Номер 12(3)

Опубликована: Дек. 5, 2021

Abstract Electrochemical clean energy conversion and the production of sustainable chemicals are critical in journey to realizing a truly society. To progress electrochemical storage devices commercialization, improving electrocatalyst performance cost utmost importance. Research into dual‐metal atom catalysts (DACs) is rising prominence due advantages these sites over single‐metal (SACs), such as breaking scaling relationships for adsorption reaction intermediates synergistic effects. This review provides an examination fundamental theoretical principles experimental DACs idealized half cells, well fuel before proceeding analyze methods used producing identifying DACs. Current challenges potential future research directions also discussed.

Язык: Английский

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A Stable and Conductive Covalent Organic Framework with Isolated Active Sites for Highly Selective Electroreduction of Carbon Dioxide to Acetate

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(36)

Опубликована: Июнь 13, 2022

Electroreduction of CO2 to acetate provides a promising strategy reduce emissions and store renewable energy, but is usually by-product. Here, we show stable conductive two-dimensional phthalocyanine-based covalent-organic framework (COF) as an electrocatalyst for reduction with single-product Faradaic efficiency (FE) 90.3(2)% at -0.8 V (vs. RHE) current density 12.5 mA cm-2 in 0.1 M KHCO3 solution. No obvious degradation was observed over 80 hours continuous operation. Combined the comparison properties other catalysts isolated metal active sites, theoretical calculations situ infrared spectroscopy revealed that copper-phthalocyanine site high electron conducive key step C-C coupling *CH3 produce acetate, can avoid *CO or *CHO ethylene ethanol.

Язык: Английский

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P‐Mediated Cu–N₄ Sites in Carbon Nitride Realizing CO₂ Photoreduction to C₂H₄ with Selectivity Modulation

Advanced Materials, Год журнала: 2022, Номер 35(3)

Опубликована: Ноя. 4, 2022

Photocatalytic CO2 reduction to high value-added C2 products (e.g., H4 ) is of considerable interest but challenging. The product selectivity strongly hinges on the intermediate energy levels in pathway. Herein, Cu-N4 sites anchored phosphorus-modulated carbon nitride (CuACs/PCN) designed as a photocatalyst tailor formation reaction pathway for realizing its production with tunable selectivity. Theoretical calculations combined experimental data demonstrate that C-C coupling intermediates can be realized and surrounding doped P facilitates . Thus, CuACs/PCN exhibits 53.2% yielding rate 30.51 µmol g-1 findings reveal significant role coordination environment microenvironment Cu single atoms offer an effective approach highly selective photoreduction produce

Язык: Английский

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Implanting Numerous Hydrogen‐Bonding Networks in a Cu‐Porphyrin‐Based Nanosheet to Boost CH₄ Selectivity in Neutral‐Media CO₂ Electroreduction

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(40), С. 21952 - 21958

Опубликована: Авг. 13, 2021

Abstract The exploration of novel systems for the electrochemical CO 2 reduction reaction (CO RR) production hydrocarbons like CH 4 remains a giant challenge. Well‐designed electrocatalysts with advantages proton generation/transferring and intermediate‐fixating efficient RR are much preferred yet largely unexplored. In this work, kind Cu‐porphyrin‐based large‐scale (≈1.5 μm) ultrathin nanosheet (≈5 nm) has been successfully applied in RR. It exhibits superior FE 70 % high current density (−183.0 mA cm −2 ) at −1.6 V under rarely reported neutral conditions maintains >51 over wide potential range (−1.5 to −1.7 V) flow cell. performance can be attributed construction numerous hydrogen‐bonding networks through integration diaminotriazine Cu‐porphyrin, which is beneficial migration intermediate stabilization, as supported by DFT calculations. This work paves new way exploring hydrogen‐bonding‐based materials catalysts.

Язык: Английский

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Tandem Photocatalysis of CO₂ to C₂H₄ via a Synergistic Rhenium-(I) Bipyridine/Copper-Porphyrinic Triazine Framework

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(14), С. 8261 - 8270

Опубликована: Март 28, 2023

The photocatalytic conversion of CO2 into C2+ products such as ethylene is a promising path toward the carbon neutral goal but remains big challenge due to high activation barrier for and similar reduction potentials many possible multi-electron-transfer products. Herein, an effective tandem photocatalysis strategy has been developed support by construction synergistic dual sites in rhenium-(I) bipyridine fac-[ReI(bpy)(CO)3Cl] (Re-bpy) copper-porphyrinic triazine framework [PTF(Cu)]. With these two catalysts, large amount can be produced at rate 73.2 μmol g-1 h-1 under visible light irradiation. However, cannot obtained from use either component Re-bpy or PTF(Cu) catalysts alone; with single catalyst, only monocarbon product CO conditions. In system, generated adsorbed nearby Cu PTF(Cu), this followed C-C coupling process which ultimately produces ethylene. Density functional theory calculations demonstrate that between PTF(Cu)-*CO Re-bpy-*CO form key intermediate Re-bpy-*CO-*CO-PTF(Cu) vital C2H4 production. This work provides new pathway design efficient photocatalysts photoconversion C2 via driven mild

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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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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Au-activated N motifs in non-coherent cupric porphyrin metal organic frameworks for promoting and stabilizing ethylene production

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Янв. 17, 2022

Abstract Direct implementation of metal-organic frameworks as the catalyst for CO 2 electroreduction has been challenging due to issues such poor conductivity, stability, and limited > 2e − products. In this study, Au nanoneedles are impregnated into a cupric porphyrin-based framework by exploiting ligand carboxylates 3+ -reducing agent, simultaneously cleaving ligand-node linkage. Surprisingly, despite lack coherent structure, Au-inserted affords superb ethylene selectivity up 52.5% in Faradaic efficiency, ranking among best reported literature. Through operando X-ray, infrared spectroscopies density functional theory calculations, enhanced is attributed Au-activated nitrogen motifs coordination with Cu centers C-C coupling at metalloporphyrin sites. Furthermore, demonstrates both improved structural catalytic ascribed altered charge conduction path that bypasses incoherent framework. This study underlines modulation reticular structure metal impregnation steering reduction reaction pathway.

Язык: Английский

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A Porous π–π Stacking Framework with Dicopper(I) Sites and Adjacent Proton Relays for Electroreduction of CO₂ to C₂₊ Products

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(29), С. 13319 - 13326

Опубликована: Июль 1, 2022

Crystalline porous materials sustained by supramolecular interactions (e.g., π–π stacking interactions) are a type of molecular crystals showing considerable stability, but their applications rarely reported due to the high difficulty construction. Herein, stable framework formed trinuclear copper(I) compound [Cu3(HBtz)3(Btz)Cl2] (CuBtz, HBtz = benzotriazole) with pyrazolate-bridged dicopper(I) sites is and employed for electrochemical CO2 reduction, an impressive performance 73.7 ± 2.8% Faradaic efficiency C2+ products [i.e., ethylene (44%), ethanol (21%), acetate (4.7%), propanol (4%)] current density 7.9 mA cm–2 at potential −1.3 V versus RHE in H-type cell Faradic (61.6%) ≈1 A reaction rate 5639 μmol m–2 s–1 −1.6 flow device, representing date. In-situ infrared spectroscopy, functional theory calculations, control experiments revealed that uncoordinated nitrogen atoms benzotriazolates immediate vicinity can act as proton relays cooperate site promote hydrogenation process *CO intermediate C–C coupling, resulting highly selective electroreduction products.

Язык: Английский

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Insight into the Effect of the d-Orbital Energy of Copper Ions in Metal–Organic Frameworks on the Selectivity of Electroreduction of CO₂ to CH₄

ACS Catalysis, Год журнала: 2022, Номер 12(5), С. 2749 - 2755

Опубликована: Фев. 11, 2022

It is of great significance to reveal the influence small differences in coordination environments metal ions catalytic active centers on selectivity products electrocatalytic CO2 reduction reaction (CO2RR). Here, two types metal–organic frameworks (MOFs) based square-pyramidal CuO5 and square-planar CuO4 nodes, respectively, are compared regard their performances CO2RR. The MOF (Cu-DBC, H8DBC = dibenzo-[g,p]chrysene-2,3,6,7,10,11,14,15-octaol) constructed by nodes catechol-derived ligands exhibit high performance for CH4 with a Faradaic efficiency 56% current density 11.4 mA cm–2 at −1.4 V vs RHE. In comparison, other MOFs, Cu-HHTP (HHTP 2,3,6,7,10,11-hexahydroxytriphenylene) Cu-THQ (THQ tetrahydroxy-1,4-quinone), ligands, that CO sole reduced product. Theoretical calculations Cu L-edge adsorption spectroscopy revealed energy levels d-orbitals (dz2, dxz, dyz) site elevated those site. As result, sites can strongly adsorb *CO intermediates hence facilitate hydrogenation into *CHO, which beneficial yielding instead CO. This work will be helpful understand mechanism copper-based catalysts hydrocarbons.

Язык: Английский

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