Tuning excited state electronic structure and charge transport in covalent organic frameworks for enhanced photocatalytic performance

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Фев. 27, 2023

Covalent organic frameworks (COFs) represent an emerging class of photocatalysts. However, their complicated structures lead to indeterminacy about photocatalytic active sites and reaction mechanisms. Herein, we use reticular chemistry construct a family isoreticular crystalline hydrazide-based COF photocatalysts, with the optoelectronic properties local pore characteristics COFs modulated using different linkers. The excited state electronic distribution transport pathways in are probed host experimental methods theoretical calculations at molecular level. One our developed (denoted as COF-4) exhibits remarkable electron utilization efficiency charge transfer properties, achieving record-high uranium extraction performance ~6.84 mg/g/day natural seawater among all techniques reported so far. This study brings new understanding operation COF-based guiding design improved photocatalysts for many applications.

Язык: Английский

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Uranium extraction from seawater by novel materials: A review

Separation and Purification Technology, Год журнала: 2023, Номер 320, С. 124204 - 124204

Опубликована: Май 27, 2023

Язык: Английский

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Recent progress of radionuclides separation by porous materials

Science China Chemistry, Год журнала: 2024, Номер 67(11), С. 3515 - 3577

Опубликована: Сен. 26, 2024

Язык: Английский

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Post-synthetic modifications of covalent organic frameworks (COFs) for diverse applications

Chemical Communications, Год журнала: 2023, Номер 59(78), С. 11631 - 11647

Опубликована: Янв. 1, 2023

Covalent organic frameworks (COFs) are porous and crystalline polymers, which have found usage in various fields. These tailorable through the introduction of diverse functionalities into platform. Indeed, functionality plays a key role their different applications. However, sometimes functional groups not compatible with reaction conditions or can compete interfere other monomers direct synthetic method. Also, pre-synthesis bulky moieties COFs negatively affect crystal formation. To avoid these problems post-synthetic modification (PSM) approach is helpful tactic. assistance this strategy size be tunable stability improved without considerable effect on crystallite. In addition, conductivity, hydrophobicity/ hydrophilicity, chirality among features that reformed review, types PSM strategies based recent articles been divided four categories: (i) post-functionalization, (ii) post-metalation, (iii) chemical locking, (iv) host-guest post-modifications. Post-functionalization locking methods covalent bond formation while post-metalation post-modifications, non-covalent bonds formed. potential post-modified energy storage conversion (lithium-sulfur batteries, hydrogen storage, proton-exchange membrane fuel cells, water splitting), heterogeneous catalysts, food safety evaluation, gas separation, environmental domains (greenhouse capture, radioactive element uptake, remediation), biological applications (drug delivery, biosensors, biomarker chiral column chromatography, solid-state smart nanochannels) discussed.

Язык: Английский

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Engineering the pore environment of antiparallel stacked covalent organic frameworks for capture of iodine pollutants

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Март 26, 2024

Abstract Radioiodine capture from nuclear fuel waste and contaminated water sources is of enormous environmental importance, but remains technically challenging. Herein, we demonstrate robust covalent organic frameworks (COFs) with antiparallel stacked structures, excellent radiation resistance, high binding affinities toward I 2 , CH 3 I, − under various conditions. A neutral framework (ACOF-1) achieves a affinity through the cooperative functions pyridine-N hydrazine groups stacking layers, resulting in capacity ~2.16 g/g for ~0.74 at 25 °C dynamic adsorption Subsequently, post-synthetic methylation ACOF-1 converted sites to cationic pyridinium moieties, yielding (namely ACOF-1R) enhanced triiodide ion water. ACOF-1R can rapidly decontaminate iodine polluted groundwater drinking levels uptake ~4.46 established column breakthrough tests. The specific moieties make promising adsorbents radioiodine pollutants treatment practical

Язык: Английский

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Uranium and lithium extraction from seawater: challenges and opportunities for a sustainable energy future

Journal of Materials Chemistry A, Год журнала: 2023, Номер 11(42), С. 22551 - 22589

Опубликована: Янв. 1, 2023

Our analysis of the current literature shows that advances in extractive technologies for U/Li recovery lie at intersection between molecular simulation, nanotechnology and materials science, electrochemistry, membrane engineering.

Язык: Английский

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Application of COFs in capture/conversion of CO2 and elimination of organic/inorganic pollutants

Environmental Functional Materials, Год журнала: 2023, Номер 2(1), С. 76 - 92

Опубликована: Март 1, 2023

Large amounts of various (in)organic pollutants and CO2 are released into the environment with fast development agriculture industry, which results in environmental pollution climate change, thereby causes great threat to human society. The efficient capture conversion critical against greenhouse effect, whereas elimination from is important health ecosystem. COFs (covalent organic frameworks) have attracted multidisciplinary research interests because their outstanding physicochemical properties such as high surface areas, tunable porous structures, abundant active sites functional groups. Herein application conversion, sorption-photocatalytic degradation pollutants, sorption-catalytic reduction-solidification heavy metals/radionuclides were reviewed compared. interaction mechanisms pollutant molecules discussed macroscopic sorption results, microscopic spectroscopy analysis, theoretical calculations. adsorption capacity was mainly related groups sites, photocatalytic activity dominated by •O2− •OH species. exhibited catalytic removal pollutants. However, there still some main challenges real applications: 1) selective low cost reusability; 2) visible light absorption for molecule degradation; 3) target selectivity 4) reduction ability in-situ solidification under complex conditions; 5) extraction radionuclides complicated solutions seawater or salt lake. In end, perspectives difficulties applications described.

Язык: Английский

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Modulating Anion Nanotraps via Halogenation for High-Efficiency ⁹⁹TcO₄^–/ReO₄^– Removal under Wide-Ranging pH Conditions

Environmental Science & Technology, Год журнала: 2023, Номер 57(29), С. 10870 - 10881

Опубликована: Июль 11, 2023

Efficient and sustainable methods for 99TcO4– removal from acidic nuclear waste streams, contaminated water, highly alkaline tank wastes are sought after. Herein, we demonstrate that ionic covalent organic polymers (iCOPs) possessing imidazolium-N+ nanotraps allow the selective adsorption of under wide-ranging pH conditions. In particular, show binding affinity cationic toward can be modulated by tuning local environment around through a halogenation strategy, thereby enabling universal removal. A parent iCOP-1 showed fast kinetics (reaching equilibrium in 1 min), high capacity (up to 1434.1 ± 24.6 mg/g), exceptional selectivity ReO4– (nonradioactive analogue 99TcO4–) water. By introducing F groups near nanotrap sites (iCOP-2), efficiency over 58% was achieved 60 min 3 M HNO3 solution. Further, introduction larger Br (iCOP-3) imparted pronounced steric effect, resulting performance super conditions low-activity streams at US legacy Hanford sites. The strategy reported herein guides task-specific design functional adsorbents other applications.

Язык: Английский

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Polyamidoxime‐Coated Coconut Haustorium Derived Magnetic Biochar Adsorbent with Photothermal Conversion for Highly Efficient Uranium Recovery from Nuclear Wastewater

Advanced Functional Materials, Год журнала: 2024, Номер unknown

Опубликована: Июнь 14, 2024

Abstract Efficient removal of uranium from uranium‐containing nuclear wastewater is great significance for utilizing resources and protecting the environment hazards. In this paper, a polyamidoxime‐coated coconut haustorium derived magnetic biochar (CHMBC‐PAO) composite adsorbent with excellent adsorption performance, magnetism, recyclability, photothermal conversion properties in complex environments prepared through simple soak‐gelation coating method efficient wastewater. The biochar, carbonized by sponge‐like organ inside sprouted coconut, can provide rich functional groups electronegative surface, which are conducive to loading materials uranyl, respectively. CHMBC‐PAO presents 2.4 emu g −1 saturation magnetization, making it be efficiently recovered recovery. It convert absorbed light into thermal energy molecular vibration non‐radiative relaxation process excitons. Enhanced effect, shows an extra high capacity 310.30 mg acidic within short period time, surpassing most reported materials. Meanwhile, also presented ion selectivity reusability. Therefore, considered as potential candidate treating radioactive

Язык: Английский

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All‐in‐One: Photo‐Responsive Lanthanide‐Organic Framework for Simultaneous Sensing, Adsorption, and Photocatalytic Reduction of Uranium

Advanced Functional Materials, Год журнала: 2024, Номер unknown

Опубликована: Май 7, 2024

Abstract The selective removal and immobilization of uranyl ions from aqueous solutions is essential for the sustainable development nuclear energy. Herein, a robust lanthanide‐organic framework material ( IHEP‐24 ) developed simultaneous fluorescence sensing, adsorption, photocatalytic reduction uranium, integrating three different functions in one material. confined space formed by coordination assembly viologen derivative ligands metal‐oxygen clusters can act as precise recognition sites uranyl, allowing to efficiently detect capture ions. In addition, presence viologen‐based radical ligand enables further adsorbed amorphous UO 2 . mechanisms adsorption photocatalysis are revealed batch experiments, photoelectrochemical characterizations, theoretical calculations. This study provides reference construction multi‐functional MOF materials also support deep radionuclides solution.

Язык: Английский

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