Insight on Reaction Pathways of Photocatalytic CO₂ Conversion

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(12), P. 7300 - 7316

Published: June 3, 2022

Photocatalytic CO2 conversion to value-added chemicals is a promising solution mitigate the current energy and environmental issues but challenging process. The main obstacles include inertness of molecule, sluggish multi-electron process, unfavorable thermodynamics, selectivity control preferable products. Furthermore, lack fundamental understanding reaction pathways accounts for very moderate performance in field. Therefore, this Perspective, we attempt discuss possible mechanisms toward all C1 C2 products, taking into account experimental evidence theoretical calculation on surface adsorption, proton electron transfer, products desorption. Finally, remaining challenges field, including mechanistic understanding, reactor design, economic consideration, potential solutions, are critically discussed by us.

Language: Английский

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Shear Stress Triggers Ultrathin-Nanosheet Carbon Nitride Assembly for Photocatalytic H₂O₂ Production Coupled with Selective Alcohol Oxidation

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(38), P. 20837 - 20848

Published: Aug. 25, 2023

Coupled photocatalysis without cocatalysts can maximize the utilization of photons and atoms, which puts forward higher demands on photocatalysts. Polymeric carbon nitride (CN) has become most promising photocatalyst, but still suffers from major drawbacks insufficient catalytic sites low quantum efficiency. Herein, we report a fluid shear stress-assisted molecular assembly to prepare ultrathin-nanosheet-assembled acanthosphere-like CN (ASCN) with nitrogen vacancy (Nv) carbonyl modification. Shear stress breaks stacking interactions between layers cuts stacked structure into ultrathin layers, are further reassembled acanthosphere bundles driven by "centrifugal force". Benefitted greatly nature that provides more exposed active improves charge carrier separation, ASCN-3 exhibits 20-fold activity than bulk counterpart toward oxygen reduction H2O2 coupled 4-methoxybenzyl alcohol (4-MBA) oxidation anisaldehyde (AA), significantly increased turnover frequency (TOF) values (TOF: 1.69 h–1 for 1.02 AA). Significantly, 95.8% conversion 4-MBA nearly 100% selectivity. High apparent yields 11.7% 9.3% at 420 nm achieved photosynthesis oxidation. Mechanism studies suggest induces holes concentrated neighboring melem unit directly oxidize Cα–H bond produce radicals, Nv as adsorption site traps electrons form superoxide radical combines shed protons H2O2. This work presents simple physical method break layered stack creating hierarchical photocatalysis.

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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Facet‐specific Active Surface Regulation of Bi_xMO_y (M=Mo, V, W) Nanosheets for Boosted Photocatalytic CO₂ reduction

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(50)

Published: Oct. 19, 2022

Photocatalytic performance can be optimized via introduction of reactive sites. However, it is practically difficult to engineer these on specific photocatalyst surfaces, because limited understanding atomic-level structure-activity. Here we report a facile sonication-assisted chemical reduction for facets regulation oxygen deprivation Bi-based photocatalysts. The modified Bi2 MoO6 nanosheets exhibit 61.5 and 12.4 μmol g-1 CO CH4 production respectively, ≈3 times greater than pristine catalyst, together with excellent stability/reproducibility ≈20 h. By combining advanced characterizations simulation, confirm the reaction mechanism surface-regulated photocatalysts, namely, induced defects highly-active surface accelerate charge separation/transfer lower energy barrier CO2 adsorption/activation/reduction. Promisingly, this method appears generalizable wider range materials.

Language: Английский

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Recent Advances in Electrochemical, Photochemical, and Photoelectrochemical Reduction of CO₂ to C₂₊ Products

Small, Journal Year: 2023, Volume and Issue: 19(16)

Published: Jan. 2, 2023

Abstract Environmental problems such as global warming are one of the most prominent challenges. Researchers investigating various methods for decreasing CO 2 emissions. The reduction reaction via electrochemical, photochemical, and photoelectrochemical processes has been a popular research topic because energy it requires can be sourced from renewable sources. converts stable molecules into useful products CO, CH 4 , C H 5 OH. To obtain economic benefits these products, is important to convert them hydrocarbons above . Numerous investigations have demonstrated uniqueness CC coupling Cu‐based catalysts conversion electrocatalysis. Herein, principle semiconductors photocatalysis briefly introduced, followed by description obstacles 2+ production. This review presents an overview mechanism hydrocarbon formation along with advances in improvement, direction, comprehension processes.

Language: Английский

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Engineering the Charge Density on an In_2.77S₄/Porous Organic Polymer Hybrid Photocatalyst for CO₂-to-Ethylene Conversion Reaction

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 145(1), P. 422 - 435

Published: Dec. 20, 2022

The development of an efficient photocatalyst for C2 product formation from CO2 is urgent importance toward the deployment solar-fuel production. Here, we report a template-free, cost-effective synthetic strategy to develop carbazole-derived porous organic polymer (POP)-based composite catalyst. catalyst comprised In2.77S4 and (POP) held together by induced-polarity-driven electrostatic interaction. Utilizing synergy catalytically active In centers light-harvesting POPs, showed 98.9% selectivity generation C2H4, with rate 67.65 μmol g-1 h-1. Two different oxidation states spinel were exploited C-C coupling process, this was investigated X-ray photoelectron spectroscopy (XPS), absorption (XAS), density functional theory (DFT) calculations. role POP elucidated via several photophysical photoelectrochemical studies. electron transfer mapped correlated approaches, which assisted in establishing Z-scheme mechanism. Furthermore, mechanism C2H4 extensively using calculations multiple possible pathways.

Language: Английский

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Isolated Single-Atom Cobalt in the ZnIn₂S₄ Monolayer with Exposed Zn Sites for CO₂ Photofixation

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(12), P. 8317 - 8329

Published: June 7, 2023

Constructing highly active photocatalysts with rich reactive sites for photofixation of CO2 organic compounds implements an environmentally friendly route valorization and carbon neutralization. Herein, we report the isolated cobalt (Co) single-atom (SA)-decorated two-dimensional (2D) single-layer ZnIn2S4 (ZIS) nanosheet composites (Co-sZIS) dual centers Co Zn fixation epoxides under visible light. The unique ensemble Co-sZIS optimizes light harvesting, promotes charge carrier separation, enriches bifunctional efficient adsorption activation reactants CO2. Consequently, exhibits significantly improved CO2-epoxide cycloaddition performance compared to bulk ZIS. In addition, synergetic photoredox manner simultaneously exploiting photogenerated electrons holes efficiently facilitates epoxides, thereby further reducing energy barrier fixation. This work not only provides a paradigm rationally interfacial engineered SA-onto-2D semiconductors but also highlights structure–activity relationship by well-defined in this SA-based hybrid platform.

Language: Английский

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Band engineering of non-metal modified polymeric carbon nitride with broad spectral response for enhancing photocatalytic CO2 reduction

Chemical Engineering Journal, Journal Year: 2023, Volume and Issue: 461, P. 141841 - 141841

Published: Feb. 10, 2023

Language: Английский

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Renaissance of elemental phosphorus materials: properties, synthesis, and applications in sustainable energy and environment

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(16), P. 5388 - 5484

Published: Jan. 1, 2023

This review summarizes the advancements in elemental phosphorus materials, focusing on fundamental physicochemical properties, synthesis, and applications sustainable energy environment.

Language: Английский

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Electronic modulation of a single-atom-based tandem catalyst boosts CO₂ photoreduction to ethanol

Energy & Environmental Science, Journal Year: 2023, Volume and Issue: 16(12), P. 5956 - 5969

Published: Jan. 1, 2023

A single-atom-based tandem photocatalyst (In 2 O 3 /Cu–O ) is fabricated for efficient CO -to-ethanol conversion. The electronic interaction between Cu and In promotes C–C coupling of *CO (on site) *COH Cu–O to form OC–COH species.

Language: Английский

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