Embedding Carbon Quantum Dots into Crystalline Polyimide Covalent Organic Frameworks to Enhance Water Oxidation for Achieving Dual-Channel Photocatalytic H₂O₂ Generation in a Wide pH Range

ACS Applied Materials & Interfaces, Journal Year: 2023, Volume and Issue: 15(37), P. 43799 - 43809

Published: Sept. 6, 2023

Photocatalytic technique is regarded as the cleanest approach for producing H2O2. Herein, two kinds of novel polyimide COFs decorated with CQDs (namely, MPa-COFs/CQDs and MNd-COFs/CQDs) were constructed by using one-pot hydrothermal method. Due to electron donor role CQDs, recombination photoinduced electrons holes was suppressed after combination CQDs. Importantly, introduction not only boosted absorbing ability toward visible light but also reduced impedance improved charge transfer efficiency. After embedded into COFs, surface hydrophilicity catalysts significantly improved, which provided convenience water oxidation reaction. Benefiting from donor-acceptor interaction between a step-by-step two-electron oxygen reduction reaction over enhanced. More interestingly, embedding can create direct pathway, played an important in photocatalytic H2O2 generation. Meanwhile, H+ generated be used form Under synergistic effects reduction, as-prepared MPa-COFs/CQDs-2 displayed excellent performance generation, its yield high 540 μmol/g within 60 min. In short, current work shared effective strategy improve production.

Language: Английский

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Carbon Catalysts Empowering Sustainable Chemical Synthesis via Electrochemical CO₂ Conversion and Two‐Electron Oxygen Reduction Reaction

Small, Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 2, 2024

Abstract Carbon materials hold significant promise in electrocatalysis, particularly electrochemical CO 2 reduction reaction (eCO RR) and two‐electron oxygen (2e − ORR). The pivotal factor achieving exceptional overall catalytic performance carbon catalysts is the strategic design of specific active sites nanostructures. This work presents a comprehensive overview recent developments electrocatalysts for eCO RR 2e ORR. creation through single/dual heteroatom doping, functional group decoration, topological defect, micro‐nano structuring, along with their synergistic effects, thoroughly examined. Elaboration on mechanisms structure‐activity relationships these provided. In addition to directly serving as electrocatalysts, this review explores role matrix support finely adjusting reactivity single‐atom molecular catalysts. Finally, addresses challenges prospects associated designing fabricating providing valuable insights into future trajectory dynamic field.

Language: Английский

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Incorporation of hydroxyl groups and π-rich electron domains into g-C3N4 framework for boosted sacrificial agent-free photocatalytic H2O2 production

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 155774 - 155774

Published: Sept. 1, 2024

Language: Английский

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Ce⁴⁺/Ce³⁺ Redox-Promoted Electron Transfer for Efficient Neutral H₂O₂ Electrosynthesis from Two-Electron Oxygen Reduction

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(9), P. 6842 - 6855

Published: April 18, 2024

Electrochemical production of H2O2 via a 2-electron oxygen reduction reaction (2e– ORR) provides clean alternative to the traditional industrial process. electrosynthesis in noncaustic neutral electrolytes is desirable for broader applications; however, it requires larger overpotentials compared those alkaline where high 2e– ORR activity can be achieved even with metal-free carbon electrocatalysts. Although ceria has been widely adopted as catalytic promoter thermo- and electrocatalytic reactions, its roles enhancing have seldom explored remain unclear. In this work, we prepared nanoparticles supported on nanotube (CeOx/CNT) composite catalysts investigated ceria's promotional effect ORR. The optimal CeOx/CNT catalyst demonstrated 1.5-fold increase CNT alone, selectivity over 87%. impedance spectroscopy indicated that improvement correlated an enhanced electron transfer (ET) rate. situ X-ray absorption near-edge structure analysis revealed counterintuitive decrease Ce3+/Ce4+ ratio applied potential was lowered. This finding suggested ET from Ce3+ O2, by further electrochemical measurements. addition, Raman participation electrocatalysis. combination tests spectroscopies proposes cascade pathway, O2 initially reduced subsequently adsorbed onto active sites.

Language: Английский

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Steering sp‐Carbon Content in Graphdiynes for Enhanced Two‐Electron Oxygen Reduction to Hydrogen Peroxide

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(23)

Published: April 9, 2024

Compared to sp

Language: Английский

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