Elevating Photooxidation of Methane to Formaldehyde via TiO₂ Crystal Phase Engineering

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(35), С. 15977 - 15987

Опубликована: Авг. 15, 2022

Photocatalytic conversion of methane to value-added products under mild conditions, which represents a long sought-after goal for industrial sustainable production, remains extremely challenging afford high production and selectivity using cheap catalysts. Herein, we present the crystal phase engineering commercially available anatase TiO2 via simple thermal annealing optimize structure-property correlation. A biphase catalyst with (90%) rutile (10%) optimal interface concentration exhibits exceptional performance in oxidation formaldehyde reaction conditions water solvent, oxygen atmosphere, full-spectrum light irradiation. An unprecedented 24.27 mmol gcat-1 an excellent 97.4% toward is acquired at room temperature after 3 h reaction. Both experimental results theoretical calculations disclose that lengthens lifetime photogenerated carriers favors formation intermediate methanol species, thus maximizing efficiency aerobic formaldehyde. More importantly, feasibility scale-up demonstrated by inventing "pause-flow" reactor. This work opens avenue transformation economical way.

Язык: Английский

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Recent advances in BiOBr-based photocatalysts for environmental remediation

Chinese Chemical Letters, Год журнала: 2021, Номер 32(11), С. 3265 - 3276

Опубликована: Апрель 2, 2021

Язык: Английский

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Direct photo-oxidation of methane to methanol over a mono-iron hydroxyl site

Nature Materials, Год журнала: 2022, Номер 21(8), С. 932 - 938

Опубликована: Июнь 30, 2022

Язык: Английский

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Recent advances in molecular oxygen activation via photocatalysis and its application in oxidation reactions

Chemical Engineering Journal, Год журнала: 2021, Номер 421, С. 129915 - 129915

Опубликована: Апрель 24, 2021

Язык: Английский

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Major routes in the photocatalytic methane conversion into chemicals and fuels under mild conditions

Applied Catalysis B Environment and Energy, Год журнала: 2021, Номер 286, С. 119913 - 119913

Опубликована: Янв. 22, 2021

Язык: Английский

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Room-Temperature Photooxidation of CH₄ to CH₃OH with Nearly 100% Selectivity over Hetero-ZnO/Fe₂O₃ Porous Nanosheets

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(27), С. 12357 - 12366

Опубликована: Июнь 28, 2022

The huge challenge for CH4 photooxidation into CH3OH lies in the activation of inert C-H bond and inhibition overoxidation. Herein, we design two-dimensional in-plane Z-scheme heterostructures composed two different metal oxides, with efforts to polarize symmetrical molecules strengthen O-H CH3OH. As a prototype, first fabricate ZnO/Fe2O3 porous nanosheets, where high-resolution transmission electron microscopy situ X-ray photoelectron spectroscopy affirm their heterostructure. In Fourier transform infrared spectra paramagnetic resonance demonstrate higher amount ·CH3 radicals relative pristine ZnO which density functional theory calculations validate that high local charge accumulation on Fe sites lowers adsorption energy from 0.14 0.06 eV. Moreover, charge-accumulated polarity through transferring electrons O atoms, confirmed by increased barrier 0.30 2.63 eV *CH3O formation, inhibits homolytic cleavage thus suppresses Accordingly, selectivity over nanosheets reaches up nearly 100% an activity 178.3 μmol-1 gcat-1, outperforming previously reported photocatalysts without adding any oxidants under room temperature ambient pressure.

Язык: Английский

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Research progress on methane conversion coupling photocatalysis and thermocatalysis

Carbon Energy, Год журнала: 2021, Номер 3(4), С. 519 - 540

Опубликована: Июль 22, 2021

Abstract Conversion of methane into value‐added chemicals is significance for utilization and industrial demand primary chemical products. The barrier associated with the nonpolar structure high bond energy C–H (4.57 eV) makes it difficult to realize conversion activation under mild conditions. photothermal synergetic strategy by combining photon thermo provides an advanced philosophy achieve efficient conversion. In this review, we overview current pioneering studies indirect present direct way photocatalysis thermocatalysis provide a fundamental understanding activation. Finally, end review discussion on remaining challenges perspectives over single‐atom catalysts via strategy.

Язык: Английский

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Single Atom Catalysts for Selective Methane Oxidation to Oxygenates

ACS Nano, Год журнала: 2022, Номер 16(6), С. 8557 - 8618

Опубликована: Май 31, 2022

Direct conversion of methane (CH4) to C1–2 liquid oxygenates is a captivating approach lock carbons in transportable value-added chemicals, while reducing global warming. Existing approaches utilizing the transformation CH4 fuel via tandemized steam reforming and Fischer–Tropsch synthesis are energy capital intensive. Chemocatalytic partial oxidation remains challenging due negligible electron affinity, poor C–H bond polarizability, high activation barrier. Transition-metal stoichiometric catalysts harsh oxidants reaction conditions perform poorly with randomized product distribution. Paradoxically, which active enough break also promote overoxidation, resulting CO2 generation reduced carbon balance. Developing can bonds selectively make useful chemicals at mild vital commercialization. Single atom (SACs) specifically coordinated metal centers on support have displayed intrigued reactivity selectivity for oxidation. SACs significantly reduce induced electrostatic polarization facilitate accelerated rate low temperature. The distinct metal–support interaction stabilize intermediate prevent overoxidation products. present review accounts recent progress field selective oxygenates. chemical nature catalytic sites, effects interaction, stabilization species minimize thoroughly discussed forward-looking perspective improve performance.

Язык: Английский

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Nearly 100% selective and visible-light-driven methane conversion to formaldehyde via. single-atom Cu and Wδ+

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

Опубликована: Май 10, 2023

Direct solar-driven methane (CH4) reforming is highly desirable but challenging, particularly to achieve a value-added product with high selectivity. Here, we identify synergistic ensemble effect of atomically dispersed copper (Cu) species and partially reduced tungsten (Wδ+), stabilised over an oxygen-vacancy-rich WO3, which enables exceptional photocatalytic CH4 conversion formaldehyde (HCHO) under visible light, leading nearly 100% selectivity, very yield 4979.0 μmol·g-1 within 2 h, the normalised mass activity 8.5 × 106 μmol·g-1Cu·h-1 HCHO at ambient temperature. In-situ EPR XPS analyses indicate that Cu serve as electron acceptor, promoting photo-induced transfer from conduction band O2, generating reactive •OOH radicals. In parallel, adjacent Wδ+ act hole acceptor preferred adsorption activation site H2O produce hydroxyl radicals (•OH), thus activate methyl (•CH3). The synergy dual active sites boosts overall efficiency selectivity process.

Язык: Английский

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Selective Photocatalytic Oxidative Coupling of Methane via Regulating Methyl Intermediates over Metal/ZnO Nanoparticles

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(23)

Опубликована: Апрель 7, 2023

Abstract Methane conversion to higher hydrocarbons requires harsh reaction conditions due high energy barriers associated with C−H bond activation. Herein, we report a systematic investigation of photocatalytic oxidative coupling methane (OCM) over transition‐metal‐loaded ZnO photocatalysts. A 1 wt % Au/ZnO delivered remarkable C 2 ‐C 4 hydrocarbon production rate 683 μmol g −1 h (83 selectivity) under light irradiation excellent photostability two days. The metal type and its interaction strongly influence the selectivity toward C−C products. Photogenerated Zn + ‐O − sites enable CH activation methyl intermediates (*CH 3 ) migrating onto adjacent nanoparticles. nature *CH ‐metal controls OCM In case Au, strong d‐σ orbital hybridization reduces metal‐C−H angles steric hindrance, thereby enabling efficient coupling. Findings indicate center may be suitable descriptor for predicting product during metal/ZnO

Язык: Английский

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