Regulating Benzene Ring Number as Connector in Covalent Organic Framework for Boosting Photosynthesis of HO from Seawater.

Photosynthesis of HO from seawater represents a promising pathway to acquire HO, but it is still restricted by the lack of a highly active photocatalyst. In this work, we propose a convenient strategy of regulating the number of benzene rings to boost the catalytic activity of materials. This is demonstrated by ECUT-COF-31 with adding two benzene rings as the connector, which can result in 1.

Ultra-selective uranium separation by in-situ formation of π-f conjugated 2D uranium-organic framework.

With the rapid development of nuclear energy, problems with uranium supply chain and nuclear waste accumulation have motivated researchers to improve uranium separation methods. Here we show a paradigm for such goal based on the in-situ formation of π-f conjugated two-dimensional uranium-organic framework. After screening five π-conjugated organic ligands, we find that 1,3,5-triformylphloroglucinol would be the best one to construct uranium-organic framework, thus resulting in 100% uranium removal from both high and low concentration with the residual concentration far below the WHO drinking water standard (15 ppb), and 97% uranium capture from natural seawater (3.

Direct Separation of UO by Coordination Sieve Effect via Spherical Coordination Traps.

Molecule sieve effect (MSE) can enable direct separation of target, thus overcoming two major scientific and industrial separation problems in traditional separation, coadsorption, and desorption. Inspired by this, herein, the concept of coordination sieve effect (CSE) for direct separation of UO , different from the previously established two-step separation method, adsorption plus desorption is reported. The used adsorbent, polyhedron-based hydrogen-bond framework (P-HOF-1), made from a metal-organic framework (MOF) precursor through a two-step postmodification approach, afforded high uptake capacity (close to theoretical value) towards monovalent Cs , divalent Sr , trivalent Eu , and tetravalent Th ions, but completely excluded UO ion, suggesting excellent CSE.

Classified Encapsulation of an Organic Dye and Metal-Organic Complex in Different Molecular Compartments for White-Light Emission and Selective Adsorption of CH over CO.

Encapsulating a certain guest molecule in an assigned molecular compartment and then endowing the corresponding potential remains a huge challenge for metal-organic frameworks. To this end, we demonstrate a good example, for the first time, based on an actinide-based MOF. The used MOF (namely, ) shows a unique uranyl-TPE anionic skeleton with three distinct cages, viz.

General Strategy to Fabricate Metal-Incorporated Pyrolysis-Free Covalent Organic Framework for Efficient Oxygen Evolution Reaction.

Because of the permission of the manipulations of modular construction on the atomic level, covalent organic frameworks (COFs) have attracted extensive attention in the electrocatalytic field. Owing to the lack of metal sites in pristine COFs constructed only by metal-free organic building units, it generally exhibits extremely low electrocatalytic activity. Thereby, linking metal sites on the backbone of pyrolysis-free COFs but not loading them on the surface to enhance the electrocatalytic activity is highly desirable but still remains a huge challenge.

Ammoniating Covalent Organic Framework (COF) for High-Performance and Selective Extraction of Toxic and Radioactive Uranium Ions.

An ideal porous adsorbent toward uranium with not only large adsorption capacity and high selectivity but also broad applicability even under rigorous conditions is highly desirable but still extremely scarce. In this work, a porous adsorbent, namely [NH][COF-SO ], prepared by ammoniating a SOH-decorated covalent organic framework (COF) enables remarkable performance for uranium extraction. Relative to the pristine SOH-decorated COF (COF-SOH) with uranium adsorption capacity of 360 mg g, the ammoniated counterpart of [NH][COF-SO ] affords ultrahigh uranium uptake up to 851 mg g, creating a 2.

Significant Enhancement of C H /C H Separation by a Photochromic Diarylethene Unit: A Temperature- and Light-Responsive Separation Switch.

A dual temperature- and light-responsive C H /C H separation switch in a diarylethene metal-organic framework (MOF) is presented. At 195 K and 100 kPa this MOF shows ultrahigh C H /C H selectivity of 47.1, which is almost 21.

Photoswitching adsorption selectivity in a diarylethene-azobenzene MOF.

The first MOF (metal-organic framework) built on both diarylethene and azobenzene photochromic units is reported here and displays distinct photoresponses for different guest molecules, thus creating an easy-to-use pathway to modulate the adsorption selectivity of MOF materials.

Reversible photo/thermoswitchable dual-color fluorescence through single-crystal-to-single-crystal transformation.

Reversible photo/thermoswitchable dual-color green-to-blue fluorescence is reported here, which is mainly due to a single-crystal-to-single-crystal (SCSC) transformation of the chromophore from a supramolecular aggregation to a covalently bonded polymer.

MOF catalysis of Fe(II)-to-Fe(III) reaction for an ultrafast and one-step generation of the Fe2O3@MOF composite and uranium(vi) reduction by iron(ii) under ambient conditions.

Herein, we demonstrate that Zn-MOF-74 enables the ultrafast and one-step generation of the Fe2O3@MOF composite once Zn-MOF-74 contacts with FeSO4 solution. This unique reaction can be further applied in catalysis of U(vi) reduction by Fe(ii) under ambient conditions. The results provide a highly renovated strategy for U(vi) reduction by Fe(ii) just under ambient conditions, which completely subvert all established methods about U(vi) reduction by Fe(ii) in which O2- and CO2-free conditions are absolutely required.

Coumarin-modified microporous-mesoporous Zn-MOF-74 showing ultra-high uptake capacity and photo-switched storage/release of U(VI) ions.

Driven by an energy crisis but consequently puzzled by various environmental problems, uranium, as the basic material of nuclear energy, is now receiving extensive attentions. In contrast to numerous sorbents applied in this field, metal-organic framework (MOFs), as a renovated material platform, has only recently been developed. How to improve the adsorption capacity of MOF materials towards U(VI) ions, as well as taking advantage of the nature of these MOFs to design photo-switched behaviour for photo-triggered storage/release of U(VI) ions are at present urgent problems and great challenges to be solved.

Novel azo-Metal-Organic Framework Showing a 10-Connected bct Net, Breathing Behavior, and Unique Photoswitching Behavior toward CO2.

Herein, we report a robust azo-metal-organic framework (MOF), namely, ECUT-15, which can be described as a 10-connected bct net built on trinuclear Co3 subunits. The activated samples of it perform a somewhat breathing behavior. Most importantly, under UV irradiation, this MOF performs outstanding photoswitching behavior toward CO2, giving great variation in the CO2 capture/release performance, for example, 45% under static conditions and 75% under dynamic measurements, as well as instantaneous release of up to 78%.