Constructing a Polyoxometalate-Based Metal–Organic Framework for Photocatalytic Oxidation of Thioethers to Sulfoxides Utilizing In Situ-Generated Superoxide Radicals

Inorganic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 15, 2025

Developing new photocatalysts for the selective oxidation of thioethers to high-value-added sulfoxides under low-oxygen mild conditions is a promising but challenging strategy. Here, polyoxometalate-based metal–organic framework (POMOF), CoBW12–TPT, was successfully synthesized, wherein continuous π···π stacking interactions and direct coordination bonds not only strengthen framework's stability also accelerate electron transfer. A series experiments theoretical studies, including control experiments, kinetic electrochemical spectroscopic analyses, paramagnetic resonance, revealed synergistic catalytic effect among Co(II) metal centers, BW12O405–, photosensitizer TPT. CoBW12–TPT applied in photocatalytic sulfoxides. Under irradiation, photoinduced transfer POMOF leads generation superoxide radicals from O2, which controls sulfoxide compounds desulfurization reaction shows good activity. In particular, it can be construction some drug molecules such as Modafinil Albendazole Oxide.

Language: Английский

---

Integrating Multipolar Structures and Carboxyl Groups in sp2‐Carbon Conjugated Covalent Organic Frameworks for Overall Photocatalytic Hydrogen Peroxide Production

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(41)

Published: July 23, 2024

Abstract The direct production of hydrogen peroxide (H 2 O ) through photocatalytic reaction via H and is considered as an ideal approach. However, the efficiency generation generally limited by insufficient charge mass transfer. Covalent organic framework (COFs) offer a promising platform metal‐free photocatalyst for due to their potential rational design at molecular level. Herein, we integrated multipolar structures carboxyl groups into COFs enhance in pure water without any sacrificial agents. introduction octupolar quadrupolar structures, along with increase planarity, created efficient oxygen reduction (ORR) sites. Meanwhile, could not only boost movement enhancement pore hydrophilicity, but also promote proton conduction, enabling conversion from ⋅O − , which crucial intermediate product photocatalysis. Overall, demonstrate that TACOF‐1‐COOH, consisting optimal enrichment sites (carboxyl groups), exhibited yield rate 3542 μmol h 1 g −1 solar‐to‐chemical (SCC) 0.55 %. This work provides valuable insights designing photocatalysts production.

Language: Английский

---

Advances of functionalized bipyridine-based covalent-organic frameworks for boosting photocatalysis

Coordination Chemistry Reviews, Journal Year: 2024, Volume and Issue: 516, P. 215997 - 215997

Published: June 5, 2024

Language: Английский

---

Robust Covalent Organic Frameworks for Photosynthesis of H₂O₂: Advancements, Challenges and Strategies

Small, Journal Year: 2024, Volume and Issue: 20(44)

Published: July 6, 2024

Abstract Since 2020, covalent organic frameworks (COFs) are emerging as robust catalysts for the photosynthesis of hydrogen peroxide (H 2 O ), benefiting from their distinct advantages. However, current efficiency H production and solar‐to‐chemical energy conversion (SCC) remain suboptimal due to various constraints in reaction mechanism. Therefore, there is an imperative propose improvement strategies accelerate development this system. This comprehensive review delineates recent advances, challenges, utilizing COFs photocatalytic production. It explores fundamentals challenges (e.g., oxygen (O ) mass transfer rate, adsorption capacity, response sunlight, electron‐hole separation efficiency, charge selectivity, desorption) associated with process, well advantages, applications, classification, preparation purpose. Various enhance performance highlighted. The aims stimulate further advancements discusses potential prospects, application areas field.

Language: Английский

---

Atomically Precise Regulation of the N-Heterocyclic Microenvironment in Triazine Covalent Organic Frameworks for Coenzyme Photocatalytic Regeneration

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(30), P. 21025 - 21033

Published: July 18, 2024

Artificial photosynthesis represents a sustainable strategy for accessing high-value chemicals; however, the conversion efficiency is significantly limited by its difficulty in cycle of coenzymes such as NADH. In this study, we report series isostructural triazine covalent organic frameworks (COFs) and explore their N-substituted microenvironment-dependent photocatalytic activity NADH regeneration. We discovered that rational alteration N-heterocyclic species, which are linked to center through an imine linkage, can regulate both electron band structure planarity COF layer. This results different separation efficiencies photoinduced electron-hole pairs transfer behavior within between individual layers. The optimal catalyst herein achieves regeneration capacity 89% 20 min, outperforming most reported nanomaterial photocatalysts. Based on this, artificial system constructed green synthesis compound,

Language: Английский

---

Bi₄O₅Br₂/COF S-Scheme Heterojunctions for Boosting H₂O₂ Photoproduction under Air and Pure Water

ACS Materials Letters, Journal Year: 2024, Volume and Issue: 6(9), P. 3932 - 3940

Published: July 26, 2024

Photosynthesizing H2O2 by the oxygen reduction reaction (ORR) and water oxidation (WOR) is a promising green avenue for generation but limited charge carrier recombination rate sluggish kinetics. Herein, Bi4O5Br2/COF step-scheme (S-scheme) heterojunction (named BIT) created first time covalent organic frameworks (TTD-COF) Bi4O5Br2, with an increased separation efficiency photosynthetic activity. Under air pure water, BIT6 exhibits highest production of 5221 μmol g–1 h–1, which 20 1.7 times greater than that individual Bi4O5Br2 TTD-COF. Subsequent mechanism analysis reveals photosynthesizes through overpowering indirect 2e– ORR paths (O2–O2• ––H2O2 O2–O2• ––O21–H2O2) weak direct WOR pathways. Moreover, in situ photogeneration process can be accompanied degradation antibiotics. This study offers in-depth insights into COF-based S-scheme heterojunctions enhanced photoproduction.

Language: Английский

---

Insights into Substituent Effects on the Fundamental Photocatalytic Processes of Covalent Organic Frameworks toward H₂ Evolution and H₂O₂ Production Reactions

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(15), P. 11262 - 11272

Published: July 13, 2024

Language: Английский

---

Facile Transformation of Imine Linkages and Functionalization of Aldehyde in the Covalent Organic Frameworks for Stable and Enhanced Photocatalytic Hydrogen Peroxide Production

ACS Applied Materials & Interfaces, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Imine-based covalent organic frameworks (COFs) have been widely applied in photocatalytic hydrogen peroxide (H2O2) production because of their highly crystalline properties and tunable chemical structures. However, the inherent polarization C═N linkage brings a high energy barrier for π-electron delocalization, impeding in-plane photoelectron transfer process, which leads to an inadequate efficiency H2O2 photosynthesis. In addition, stability most imine-COFs remains insufficient due reversible nature imine linkage. Herein, quinoline-linked COF (Ald-TTB-TTA) bearing polar aldehyde groups was constructed by postsynthetic conversion (TTB-TTA). The expanded conjugate planes facilitate charge transfer, accelerating proton-coupled electron oxygen reduction reaction (ORR) process. As expected, Ald-TTB-TTA achieves considerable rate 3169 μmol g–1 h–1 without sacrificial agent, surpassing its imine-linked counterpart (1944 h–1). Therefore, this work provides facile strategy designing functional COFs is expected aid construction high-performance catalysts photosynthesis H2O2.

Language: Английский

---

Linkage Microenvironment Modulation in Triazine‐Based Covalent Organic Frameworks for Enhanced Photocatalytic Hydrogen Peroxide Production

Small, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 26, 2025

Abstract Covalent organic frameworks (COFs), known for the precise tunability of molecular structures, hold significant promise photocatalytic hydrogen peroxide (H 2 O ) production. Herein, by systematically altering quinoline (QN) linkages in triazine (TA)‐based COFs via multi‐component reactions, six R‐QN‐TA‐COFs are synthesized with identical skeletons but different substituents. The fine‐tuning optoelectronic properties and local microenvironment is allowed, thereby optimizing charge separation improving interactions dissolved oxygen. Consequently, MeO‐QN‐TA‐COF customized to achieve an impressive rate H production up 7384 µmol g⁻ 1 h⁻ under air atmosphere water without any sacrificial agents, surpassing most reported COF photocatalysts. Its high stability demonstrated through five consecutive recycling experiments characterization recovered COF. reaction mechanism further investigated using a suite quenching experiments, situ spectroscopic analysis, theoretical calculations. enhanced over 2e⁻ oxygen reduction oxidation pathways. Overall, crucial role linkage modulation design solar‐driven effective

Language: Английский

---

Promoting Proton Donation through Hydrogen Bond Breaking on Carbon Nitride for Enhanced H₂O₂ Photosynthesis

ACS Nano, Journal Year: 2024, Volume and Issue: 18(31), P. 20435 - 20448

Published: July 26, 2024

Photocatalytic H2O2 production has attracted much attention as an alternative way to the industrial anthraquinone oxidation process but is limited by weak interaction between catalysts and reactants well inefficient proton transfer. Herein, we report on a hydrogen-bond-broken strategy in carbon nitride for enhancement of photosynthesis without any sacrificial agent. The promoted hydrogen bond formation exposed N atoms H2O molecules, which enhances proton-coupled electron transfer therefore photocatalytic activity. serve buffering sites from molecules nitride. also enhanced through adsorption reduction O2 gas toward because nitrogen vacancies (NVs) cyano groups after intralayer breaking A high light-to-chemical conversion efficiency (LCCE) value 3.85% achieved. are found undergo one-step two-electron pathway photogenerated hot electrons four-electron produce gas, respectively. Density functional theory (DFT) calculations validate reaction pathways. This study elucidates significance catalyst reactants, greatly increases tunneling dynamics.

Language: Английский

---