Multifunctional carbon nitride nanoarchitectures for catalysis

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(21), P. 7602 - 7664

Published: Jan. 1, 2023

Carbon nitrides, with feasibility of tailored band gap via suitable nanoarchitectonics, are deemed as best catalysts amongst existing materials, especially for HER, OWS, COR, NRR, water oxidation, pollutant removal, and organocatalysis.

Language: Английский

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Unraveling the Synergy Mechanism between Photocatalysis and Peroxymonosulfate Activation on a Co/Fe Bimetal-Doped Carbon Nitride

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(13), P. 8973 - 8986

Published: June 22, 2023

Fenton-like catalysis based on peroxymonosulfate (PMS) activation has shown great potential in the treatment of organic wastewater. Heterogeneous catalysts containing transition metal active sites are highly efficient for PMS activation. However, reduction oxidized was usually not prompt due to sluggish reaction kinetics, which caused insufficient redox cycle and further hampered efficiency. Recent studies have that synergy effect between photocatalysis may address above obstacle boost overall a deeper understanding this is still missing, making it difficult be rationally controlled; thus, poor frequently reported. Herein, Co/Fe bimetal-doped graphitic carbon nitride (g-C3N4) designed representatively through systematical characterization theoretical calculation, revealed profoundly determined by competitive role hole system adsorbed metastable PMS* catalyst surface, furthermore, can manipulated; when doping ratio 2.5:2.5, as-prepared g-C3N4 with moderate valence band position endow an optimized photo-Fenton-like synergistic highest catalytic degradation performance. This work sheds light rational design catalysts.

Language: Английский

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Surface plasmon effect combined with S-scheme charge migration in flower-like Ag/Ag6Si2O7/Bi12O17Cl2 enables efficient photocatalytic antibiotic degradation

Applied Surface Science, Journal Year: 2024, Volume and Issue: 679, P. 161303 - 161303

Published: Sept. 23, 2024

Language: Английский

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Carbon Nitrides with Grafted Dual-Functional Ligands as Electron Acceptors and Active Sites for Ultra-stable Photocatalytic H₂O₂ Production

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(15), P. 10474 - 10486

Published: July 26, 2023

Photocatalytic production of H2O2 from earth-abundant water and oxygen using low-cost metal-free carbon nitrides (CNs) through reduction is a prospective route toward greener future. However, the productivity restricted by rapid electron–hole separation low activity CNs. Herein, we rationally designed series CNs with covalently bonded dual-functional ligands acting as electron acceptors active sites to achieve high photocatalytic superior stability. The best-performing nitride displays rate 7.3 mmol/g h an apparent quantum efficiency 20.2% at 420 nm formic acid donor. Moreover, modified show excellent stable generation over 110 without significant decline. Mechanistic studies reveal that was produced 2e– reaction route. Photoluminescence, photo-electrochemical, Kelvin probe force microscopy results together theoretical calculations have revealed performance originates ligand. It not only acts acceptor promote photogenerated charge carrier withdrawing electrons but also works site accelerate lowering adsorption activation energy. this facial strategy grafting provides universal approach synthesize photocatalysts enhanced reactivity under mild conditions choosing proper for specific reaction.

Language: Английский

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Accumulation of Long‐Lived Photogenerated Holes at Indium Single‐Atom Catalysts via Two Coordinate Nitrogen Vacancy Defect Engineering for Enhanced Photocatalytic Oxidation

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(28)

Published: May 11, 2024

Visible-light-driven photocatalytic oxidation by photogenerated holes has immense potential for environmental remediation applications. While the electron-mediated photoreduction reactions are often at spotlight, active possess a remarkable capacity that can degrade recalcitrant organic pollutants, resulting in nontoxic byproducts. However, random charge transfer and rapid recombination of electron-hole pairs hinder accumulation long-lived reaction center. Herein, novel method employing defect-engineered indium (In) single-atom photocatalysts with nitrogen vacancy (Nv) defects, dispersed carbon nitride foam (In-Nv-CNF), is reported to overcome these challenges make further advances photocatalysis. This Nv strategy produces extension lifetime an increase concentration In-Nv-CNF. Consequently, optimized In-Nv-CNF demonstrates 50-fold photo-oxidative degradation rate compared pristine CN, effectively breaking down two widely used antibiotics (tetracycline ciprofloxacin) under visible light. The contaminated water treated completely based on growth Escherichia coli. Structural-performance correlations between defect engineering hole established validated through experimental theoretical agreement. work elevate efficiency overall from hole-centric standpoint.

Language: Английский

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Z-Scheme Heterojunction α-Fe₂O₃/Tubular g-C₃N₄ with C Defects for Photocatalytic Degradation of Microcystin-LR in Water: Generation and Effect of Critical Species ¹O₂

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(8), P. 6272 - 6291

Published: April 10, 2024

Microcystin-LR (MC-LR) is susceptible to degradation by singlet oxygen (1O2) attack due multiple unsaturated olefinic bond sites. In this study, the Z-scheme heterojunction α-Fe2O3/tubular g-C3N4 with C defects (α-Fe2O3/TDCN) was synthesized via hydrothermal and cocalcination methods. The efficient generation of 1O2 realized enhancing photogenerated carrier separation adsorption capabilities used investigate process mechanism MC-LR. results show that rate MC-LR can reach nearly 100% within 60 min under visible light irradiation, α-Fe2O3/TDCN possesses good stability environmental friendliness. relationship between photocatalyst performance analyzed density functional theory (DFT) calculations. Based on probe experiments, LC–MS data, DFT calculations, mineralization dominated analyzed. This study provides a reference for addressing pollution in eutrophic aquatic environments direction specific control mineralization.

Language: Английский

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Morphology and Light‐Dependent Spatial Distribution of Spin Defects in Carbon Nitride

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(43)

Published: Sept. 8, 2022

Carbon nitride (CN) is a heterogeneous photocatalyst that combines good structural properties and broad scope. The photocatalytic efficiency of CN associated with the presence defective radical species. An accurate description states-both at local extended level-is key to develop thorough mechanistic understanding photophysics CN. In turn, this will maximise generation usage photogenerated charge carriers minimise wasteful recombination. Here influence morphology light-excitation on number chemical nature defects assessed. By exploiting magnetic dipole-dipole coupling, spatial distribution native radicals in derived high precision. From analysis an average distance range 1.99-2.34 nm determined, which corresponds pairs located approximately four tri-s-triazine units apart.

Language: Английский

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Carbon Vacancies Steer the Activity in Dual Ni Carbon Nitride Photocatalysis

Advanced Science, Journal Year: 2023, Volume and Issue: 10(26)

Published: July 6, 2023

The manipulation of carbon nitride (CN) structures is one main avenue to enhance the activity CN-based photocatalysts. Increasing efficiency photocatalytic heterogeneous materials a critical step toward realistic implementation sustainable schemes for organic synthesis. However, limited knowledge structure/activity relationship in relation subtle structural variations prevents fully rational design new materials, limiting practical applications. Here, CN structure engineered by means microwave treatment, and material shaped around its suitable functionality Ni dual photocatalysis, with resulting boosting reaction many CX (X = N, S, O) couplings. combination advanced characterization techniques first-principle simulations reveals that this enhanced reactivity due formation vacancies evolve into triazole imine N species able suitably bind complexes harness highly efficient catalysis. cost-effective treatment proposed here appears as versatile approach photocatalysts wide range industrially relevant synthetic reactions.

Language: Английский

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Boosting C₃H₆ Epoxidation via Tandem Photocatalytic H₂O₂ Production over Nitrogen-Vacancy Carbon Nitride

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(19), P. 13101 - 13110

Published: Sept. 25, 2023

Propylene oxide (PO) is an important raw material in the plastics industry. The propylene epoxidation using O2 without H2 and noble metals considered a fantasy reaction. Here we constructed tandem system for photocatalytic situ H2O2 production epoxidation. In this transformation system, prepared carbon nitride containing N3C vacancies one step by synergistic action of argon pyrolysis supramolecular self-assembly precursor. introduction significantly promoted photogenerated electron–hole separation enhanced adsorption H+ excellent performance (5775 μmol/g/h) via dual paths involving ·O2– 1O2. To avoid purification H2O2, compatible solvent consisting methanol water was utilized to promote both PO. Benefiting from them, PO efficiency came 5515 μmol/g/h with selectivity 99.1%. This work not only opened up idea but also provided reference creating more systems series photosynthetic H2O2.

Language: Английский

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MOF-Derived Defective Co₃O₄ Nanosheets in Carbon Nitride Nanocomposites for CO₂ Photoreduction and H₂ Production

ACS Applied Materials & Interfaces, Journal Year: 2023, Volume and Issue: 15(5), P. 6817 - 6830

Published: Jan. 31, 2023

In photocatalysis, especially in CO2 reduction and H2 production, the development of multicomponent nanomaterials provides great opportunities to tune many critical parameters toward increased activity. This work reports tunable organic/inorganic heterojunctions comprised cobalt oxides (Co3O4) varying morphology modified carbon nitride (CN), targeting on optimizing their response under UV-visible irradiation. MOF structures were used as precursors for synthesis Co3O4. A facile solvothermal approach allowed ultrathin two-dimensional (2D) Co3O4 nanosheets (Co3O4-NS). The optimized CN coupled forming heterojunctions, content each part was optimized. Activity significantly improved nanocomposites bearing Co3O4-NS compared with corresponding bulk Co3O4/CN composites. Transient absorption spectroscopy revealed a 100-fold increase charge carrier lifetime sites composite bare Co3O4-NS. photocatalytic activity production is linked (a) larger interface imposed from matching 2D structure planar surface CN, (b) improvements lifetime, (c) enhanced adsorption. study highlights importance advanced materials stepwise functionalization individual parts superior

Language: Английский

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