Surface Modification of 2D Photocatalysts for Solar Energy Conversion

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(23)

Published: March 9, 2022

Abstract 2D materials show many particular properties, such as high surface‐to‐volume ratio, anisotropic degree, and adjustable chemical functionality. These unique properties in have sparked immense interest due to their applications photocatalytic systems, resulting significantly enhanced light capture, charge‐transfer kinetics, surface reaction. Herein, the research progress photocatalysts based on varied compositions functions, followed by specific modification strategies, is introduced. Fundamental principles focusing harvesting, charge separation, molecular adsorption/activation 2D‐material‐based system are systemically explored. The examples described here detail use of various energy‐conversion including water splitting, carbon dioxide reduction, nitrogen fixation, hydrogen peroxide production, organic synthesis. Finally, elaborating challenges possible solutions for developing these materials, review expected provide some inspiration future used efficient energy conversions.

Language: Английский

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Engineering Single-Atom Active Sites on Covalent Organic Frameworks for Boosting CO₂ Photoreduction

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(37), P. 17097 - 17109

Published: Sept. 6, 2022

Solar carbon dioxide (CO2) conversion is an emerging solution to meet the challenges of sustainable energy systems and environmental/climate concerns. However, construction isolated active sites not only influences catalytic activity but also limits understanding structure-catalyst relationship CO2 reduction. Herein, we develop a universal synthetic protocol fabricate different single-atom metal (e.g., Fe, Co, Ni, Zn, Cu, Mn, Ru) anchored on triazine-based covalent organic framework (SAS/Tr-COF) backbone with bridging structure metal-nitrogen-chlorine for high-performance Remarkably, as-synthesized Fe SAS/Tr-COF as representative catalyst achieved impressive CO generation rate high 980.3 μmol g-1 h-1 selectivity 96.4%, over approximately 26 times higher than that pristine Tr-COF under visible light irradiation. From X-ray absorption fine analysis density functional theory calculations, superior photocatalytic performance attributed synergic effect atomically dispersed host, decreasing reaction barriers formation *COOH intermediates promoting adsorption activation well desorption. This work affords rational design state-of-the-art catalysts at molecular level provides in-depth insights efficient conversion.

Language: Английский

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Synergy between Palladium Single Atoms and Nanoparticles via Hydrogen Spillover for Enhancing CO₂ Photoreduction to CH₄

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(16)

Published: Feb. 25, 2022

Selective photoreduction of carbon dioxide (CO2 ) into carbon-neutral fuels such as methane (CH4 is extremely desirable but remains a challenge since sluggish multiple proton-electron coupling transfer and various C1 intermediates are involved. Herein, synergistic function between single Pd atoms (Pd1 nanoparticles (PdNPs on graphitic nitride (C3 N4 for photocatalytic CO2 methanation presented. The catalyst achieves high selectivity 97.8% CH4 production with yield 20.3 µmol gcat.-1 h-1 in pure water. Mechanistic studies revealed that Pd1 sites activated , while PdNPs boosted water (H2 O) dissociation increased H* coverage. produced by migrate to the promote via hydrogen spillover. Moreover, adjacent effectively stabilized *CHO, thereby favoring pathway production. This work provides new perspective development selective conversion through artful design catalytic sites.

Language: Английский

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P and Cu Dual Sites on Graphitic Carbon Nitride for Photocatalytic CO₂Reduction to Hydrocarbon Fuels with High C₂H₆Evolution

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(40)

Published: Aug. 15, 2022

The light-driven CO2 reduction to multi-carbon products is especially meaningful, while the low efficiency of multi-electron transfer and sluggish C-C coupling greatly hinder its development. Herein, we report a photocatalyst comprising P Cu dual sites anchored on graphitic carbon nitride (P/Cu SAs@CN), which achieves high C2 H6 evolution rate 616.6 μmol g-1 h-1 in reducing hydrocarbons. detailed spectroscopic characterizations identify formation charge-enriched sites, where isolated atoms serve as hole capture during photocatalysis. Theoretical simulations combined with situ FTIR measurement reveal kinetically feasible process for intermediate (*OC-COH) confirm favorable production P/Cu SAs@CN photocatalyst. This work offers new insights into design atomic precision toward highly efficient photocatalytic conversion value-added products.

Language: Английский

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Carbon Nitride Photocatalysts with Integrated Oxidation and Reduction Atomic Active Centers for Improved CO₂Conversion

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(34)

Published: June 18, 2022

Single-atom active-site catalysts have attracted significant attention in the field of photocatalytic CO2 conversion. However, designing active sites for reduction and H2 O oxidation simultaneously on a photocatalyst combining corresponding half-reaction system is still difficult. Here, we synthesized bimetallic single-atom with two compatible centers Mn Co carbon nitride (Mn1 Co1 /CN). Our experimental results density functional theory calculations showed that center promotes by accumulating photogenerated holes. In addition, activation increasing bond length angle molecules. Benefiting from synergistic effect atomic centers, Mn1 /CN exhibited CO production rate 47 μmol g-1 h-1 , which significantly higher than single-metal photocatalyst.

Language: Английский

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Solar Energy Catalysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(29)

Published: April 26, 2022

When it comes to using solar energy promote catalytic reactions, photocatalysis technology is the first choice. However, sunlight can not only be directly converted into chemical through a photocatalytic process, also different energy-transfer pathways. Using as source, reactions proceed independently, and coupled with other technologies enhance overall efficiency. Therefore, sunlight-driven are diverse, need given specific definition. We propose timely perspective for driven by give them definition, namely "solar catalysis". The concept of types catalysis, such photocatalysis, photothermal cell powered electrocatalysis, pyroelectric highlighted. Finally, their limitations future research directions discussed.

Language: Английский

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Phosphorus Tailors thed‐Band Center of Copper Atomic Sites for Efficient CO₂Photoreduction under Visible‐Light Irradiation

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(38)

Published: July 8, 2022

Photoreduction of CO2 into solar fuels has received great interest, but suffers from low catalytic efficiency and poor selectivity. Herein, two single-Cu-atom catalysts with unique Cu configurations in phosphorus-doped carbon nitride (PCN), namely, Cu1 N3 @PCN P3 were fabricated via selective phosphidation, tested visible light-driven reduction by H2 O without sacrificial agents. was exclusively active for CO production a rate 49.8 μmolCO gcat-1 h-1 , outperforming most polymeric (C3 N4 ) based catalysts, while preferably yielded . Experimental theoretical analysis suggested that doping P C3 replacing corner C atom upshifted the d-band center close to Fermi level, which boosted adsorption activation on making efficiently convert CO. In contrast, much lower 3d electron energy exhibited negligible adsorption, thereby preferring formation photocatalytic splitting.

Language: Английский

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Atomically Dispersed Au-Assisted C–C Coupling on Red Phosphorus for CO₂ Photoreduction to C₂H₆

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(48), P. 22075 - 22082

Published: Nov. 22, 2022

Single-atom catalysts have exhibited great potential in the photocatalytic conversion of CO2 to C2 products, but generation gaseous multi-carbon hydrocarbon products is still challenging. Previously, supports a single atom consist multiple elements, making C-C coupling difficult because coordination environment single-atom sites diversified and control. Here, we steer by implanting an Au on red phosphorus (Au1/RP), support with uniform structure composed element, lower electronegativity, better ability absorb CO2. The electron-rich atoms near can function as active for activation. effectively reduce energy barrier coupling, boosting reaction kinetics formation C2H6. Notably, C2H6 selectivity turnover frequency Au1/RP reach 96% 7.39 h-1 without sacrificial agent, respectively, which almost represents best photocatalyst chemical synthesis date. This research will provide new ideas design high-efficiency photocatalysts products.

Language: Английский

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Single-Atom Cu Channel and N-Vacancy Engineering Enables Efficient Charge Separation and Transfer between C₃N₄ Interlayers for Boosting Photocatalytic Hydrogen Production

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(9), P. 6280 - 6288

Published: April 21, 2023

Polymeric carbon nitride (C3N4) has attracted great attention in photocatalysis due to its low-cost, visible-light response, and environment-friendly merits. However, the catalytic efficiency of pristine bulk C3N4 is severely limited by poor photoinduced electron/hole pair separation interlayer charge transport. Herein, single-atom Cu bridged into sheet interlayers through thermal condensation self-assembly supramolecules precursors melamine–cyanuric acid monomers. Simultaneously, N vacancies are engineered only gradient temperature. The bridges serve as electron channels promote experimental results calculations demonstrate that break symmetry C3N4, allowing more electrons pass delocalized π-conjugated network sites, which facilitates transfer between layers, resulting effective pairs, optimal distribution, lower hydrogen evolution barrier. As a result, photocatalyst at stationary point with 1 wt % Pt cocatalyst presents high photocatalytic production rate (11.23 mmol g–1 h–1), reaching apparent quantum yield 31.60% 420 nm. It noted still exhibits 605.15 μmol h–1 absence cocatalyst.

Language: Английский

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Improving CO2 photoconversion with ionic liquid and Co single atoms

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: March 16, 2023

Photocatalytic CO2 conversion promises an ideal route to store solar energy into chemical bonds. However, sluggish electron kinetics and unfavorable product selectivity remain unresolved challenges. Here, ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate, borate-anchored Co single atoms were separately loaded on ultrathin g-C3N4 nanosheets. The optimized nanocomposite photocatalyst produces CO CH4 from water under UV-vis light irradiation, exhibiting a 42-fold photoactivity enhancement compared with nearly 100% towards reduction. Experimental theoretical results reveal that the liquid extracts electrons facilitates reduction, whereas trap holes catalyze oxidation. More importantly, maximum transfer efficiency for photoreduction, as measured in-situ μs-transient absorption spectroscopy, is found be 35.3%, owing combined effect of atoms. This work offers feasible strategy efficiently converting valuable chemicals.

Language: Английский

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