Enabling Specific Photocatalytic Methane Oxidation by Controlling Free Radical Type

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(4), С. 2698 - 2707

Опубликована: Янв. 17, 2023

Selective CH4 oxidation to CH3OH or HCHO with O2 in H2O under mild conditions provides a desired sustainable pathway for synthesis of commodity chemicals. However, manipulating reaction selectivity while maintaining high productivity remains huge challenge due the difficulty kinetic control formation oxygenate against its overoxidation. Here, we propose highly efficient strategy, based on precise type as-formed radicals by rational design photocatalysts, achieve both and photooxidation first time. Through tuning band structure size active sites (i.e., single atoms nanoparticles) our Au/In2O3 catalyst, show alternative two important radicals, •OOH •OH, which leads distinctly different paths HCHO, respectively. This approach gives rise remarkable yield 97.62% 6.09 mmol g-1 In2O3-supported Au (Au1/In2O3) an exceptional 89.42% 5.95 nanoparticles (AuNPs/In2O3), respectively, upon photocatalytic 3 h at room temperature. work opens new avenue toward selective delicate composite photocatalysts.

Язык: Английский

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Catalyzing Artificial Photosynthesis with TiO₂ Heterostructures and Hybrids: Emerging Trends in a Classical yet Contemporary Photocatalyst

Advanced Materials, Год журнала: 2023, Номер 36(17)

Опубликована: Окт. 11, 2023

Titanium dioxide (TiO

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Recent Progress on Phase Engineering of Nanomaterials

Chemical Reviews, Год журнала: 2023, Номер 123(23), С. 13489 - 13692

Опубликована: Ноя. 14, 2023

As a key structural parameter, phase depicts the arrangement of atoms in materials. Normally, nanomaterial exists its thermodynamically stable crystal phase. With development nanotechnology, nanomaterials with unconventional phases, which rarely exist their bulk counterparts, or amorphous have been prepared using carefully controlled reaction conditions. Together these methods are beginning to enable engineering (PEN), i.e., synthesis phases and transformation between different obtain desired properties functions. This Review summarizes research progress field PEN. First, we present representative strategies for direct modulation diverse kinds nanomaterials. We cover ranging from metal nanostructures such as Au, Ag, Cu, Pd, Ru, alloys; oxides, borides, carbides; transition dichalcogenides (TMDs) 2D layered review growth wet-chemical reduction seed-mediated epitaxial chemical vapor deposition (CVD), high pressure transformation, electron ion-beam irradiation. After that, summarize significant influence on various unconventional-phase also discuss potential applications developed areas including catalysis, electrochemical energy storage (batteries supercapacitors), solar cells, optoelectronics, sensing. Finally, existing challenges future directions

Язык: Английский

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Crystal Engineering of TiO₂ for Enhanced Catalytic Oxidation of 1,2-Dichloroethane on a Pt/TiO₂ Catalyst

Environmental Science & Technology, Год журнала: 2023, Номер 57(17), С. 7086 - 7096

Опубликована: Апрель 18, 2023

Crystal engineering of metal oxide supports represents an emerging strategy to improve the catalytic performance noble catalysts in oxidation chlorinated volatile organic compounds (CVOCs). Herein, Pt on a TiO2 support with different crystal phases (rutile, anatase, and mixed phase (P25)) were prepared for 1,2-dichloroethane (DCE). The catalyst P25-TiO2 (Pt/TiO2-P) showed optimal activity, selectivity, stability, even under high-space velocity humidity conditions. Due strong interaction between originating from more lattice defects TiO2, Pt/TiO2-P possessed stable Pt0 Pt2+ species during DCE superior redox property, resulting high activity stability. Furthermore, abundant hydroxyl groups, which prompted removal chlorine form HCl significantly decreased selectivity vinyl chloride (VC) as main byproduct. On other hand, exhibited reaction path, groups its surface activated VC enolic species, besides oxygen rutile anatase TiO2. This work provides guidance rational design CVOCs.

Язык: Английский

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Exposed Zinc Sites on Hybrid ZnIn₂S₄@CdS Nanocages for Efficient Regioselective Photocatalytic Epoxide Alcoholysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(22)

Опубликована: Март 29, 2023

Photocatalytic epoxide alcoholysis through C-O bond cleavage and formation has emerged as an alternative to synthesizing anti-tumoral pharmaceuticals fine chemicals. However, the lack of crucial evidence interpret interaction between reactants photocatalyst surface makes it challenging for photocatalytic with both high activity regioselectivity. In this work, we report hierarchical ZnIn2 S4 @CdS regioselectivity nearly 100 %. Mechanistic studies unveil that precise activation switch on exposed Zn acid sites polarization a critical significance achieving efficient performance. Furthermore, establishment Z-scheme heterojunction facilitates interface charge separation transfer. Remarkably, underlying regioselective reaction pathway been distinctly revealed.

Язык: Английский

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Constructing matched active sites for robust photocatalytic dry reforming of methane

Chem, Год журнала: 2023, Номер 9(11), С. 3224 - 3244

Опубликована: Июль 25, 2023

Язык: Английский

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Atomically Strained Metal Sites for Highly Efficient and Selective Photooxidation

Nano Letters, Год журнала: 2023, Номер 23(7), С. 2905 - 2914

Опубликована: Март 24, 2023

Strain engineering is an attractive strategy for improving the intrinsic catalytic performance of heterogeneous catalysts. Manipulating strain on short-range atomic scale to local structure sites still challenging. Herein, we successfully achieved modulation ultrathin layered vanadium oxide nanoribbons by ingenious intercalation chemistry method. When trace sodium cations were introduced between V2O5 layers (Na+-V2O5), V-O bonds stretched atomically strained sites, redistributing charges. The Na+-V2O5 demonstrated excellent photooxidation performance, which was approximately 12 and 14 times higher than that pristine VO2, respectively. Complementary spectroscopy analysis theoretical calculations confirmed had a high surficial charge density, activation oxygen molecules contributing photocatalytic property. This work provides new approach rational design strain-equipped catalysts selective reactions.

Язык: Английский

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Photodriven Methane Conversion on Transition Metal Oxide Catalyst: Recent Progress and Prospects

Advanced Science, Год журнала: 2023, Номер 11(8)

Опубликована: Окт. 26, 2023

Methane as the main component in natural gas is a promising chemical raw material for synthesizing value-added chemicals, but its harsh conversion process often causes severe energy and environment concerns. Photocatalysis provides an attractive path to active convert methane into various products under mild conditions with clean sustainable solar energy, although many challenges remain at present. In this review, recent advances photocatalytic are systematically summarized. As basis of conversion, activation first elucidated from structural molecules. The study committed categorizing elucidating research progress laws intricate reactions according target products, including partial oxidation, reforming, coupling, combustion, functionalization. Advanced reactor designs also designed enrich options reliability performance evaluation. prospects discussed, which turn offers guidelines methane-conversion-related photocatalyst exploration, reaction mechanism investigation, advanced photoreactor design.

Язык: Английский

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Crystal-Phase Engineering in Heterogeneous Catalysis

Chemical Reviews, Год журнала: 2023, Номер 124(1), С. 164 - 209

Опубликована: Дек. 4, 2023

The performance of a chemical reaction is critically dependent on the electronic and/or geometric structures material in heterogeneous catalysis. Over past century, Sabatier principle has already provided conceptual framework for optimal catalyst design by adjusting structure catalytic via change composition. Beyond composition, it essential to recognize that atomic catalyst, encompassing terraces, edges, steps, kinks, and corners, have substantial impact activity selectivity reaction. Crystal-phase engineering capacity bring about alterations configurations enabling control over coordination numbers, morphological features, arrangement surface atoms. Modulating crystallographic phase therefore an important strategy improving stability, activity, materials. Nonetheless, complete understanding how depends crystal remains elusive, primarily due absence molecular-level view active sites across various phases. In this review, we focus assessing dependence phases elucidate challenges complexities inherent catalysis, ultimately aiming improved design.

Язык: Английский

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Highly Selective Photocatalytic Methane Coupling by Au-Modified Bi₂WO₆

ACS Catalysis, Год журнала: 2024, Номер 14(3), С. 1855 - 1861

Опубликована: Янв. 19, 2024

Photocatalytic oxidative coupling of methane (OCM) to ethane promises a route value-added C2 products from an abundant and low-cost feedstock. However, selective activation the C–H bond CH4 without overoxidation CO2 has been major challenge. In this work, we present use Au-modified Bi2WO6 as prototypical photocatalyst, demonstrating high performance OCM through photocatalysis. A C2H6 production rate at 1.69 × 103 μmol·g–1·h–1 with approximately 85% selectivity was achieved, which ranks among top-performing photocatalytic systems. Efforts were also made in establishing correlation between improved photocatalyst system by examining nature oxide photocatalyst. Our findings indicated that oxygen within surface, likely adsorbed subsequently dissociated vacancy sites, afforded desired reactivity selectively activate significant overoxidation. Surprisingly, it revealed Au cocatalyst plays dual roles activating for enhanced promoting C–C yield main product.

Язык: Английский

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