Linkage Regulation of β-Ketoamine Covalent Organic Frameworks for Boosting Photocatalytic Overall Water Splitting.

Two dimensional β-ketoamine covalent organic frameworks (2D TP-COFs) are one category of promising metal-free catalysts for photocatalytic overall water splitting (OWS) because of their unusual stability and versatile electronic/optical properties. However, none of the currently reported TP-COFs can accomplish the hydrogen evolution (HER) and oxygen evolution reactions (OER) simultaneously without adding any sacrificial agents and cocatalysts. To address this challenging issue, we rationally designed 23 2D TP-COFs by regulating the linkage groups and comprehensively evaluated their OWS activity by using the first-principles method.

CdWO Sub-1 nm Nanowires for Visible-Light CO Photoreduction.

Quantum size effect usually causes energy level splitting and band broadening as material size decreases. However, this may change again by the surface adsorbents, doping and defects, which rarely attracts much attention. Herein, CdWO sub-1 nm nanowires (SNWs) with oleylamine adsorption, PO -doping and oxygen defects are synthesized by combining Cd(CHCOO), HPWO (PW) and oleylamine (abbreviated as PO -CdWO-X SNWs).

Relationship between Circulating 25-Hydroxyvitamin D and Metabolic Syndrome in Chinese Adults: A Large Nationwide Longitudinal Study.

Objective: This study investigated the association of circulating levels of 25-hydroxyvitamin D (25[OH]D) with the risk of metabolic syndrome (MetS) and its components in adults.

Methods: This nationwide cohort involved 23,810 Chinese adults attending annual health evaluations. Serum 25(OH)D levels, MetS status, and covariates were determined at each examination.

Tunable covalent benzo-heterocyclic rings constructed using two-dimensional conjugated polymers for visible-light-driven water splitting.

Developing highly efficient, stable, and cost-effective two-dimensional (2D) conjugated polymers (CPs) for overall water splitting (OWS) is critical for producing clean and renewable hydrogen energy, yet it remains a great challenge. Here, we designed eight 2D CPs through the topological assembly of diacetylene and benzene-derived molecular linkers that can offer active sites for hydrogen and oxygen evolution reactions, and explored their structural, electronic, optical, and photocatalytic OWS properties by performing first-principles computations. It is shown that incorporating benzo-heterocyclic rings into CPs can significantly modulate the electronic structures of CPs and broaden the spectral absorption, suitable for visible-light-driven OWS.

Predictors of successful endovascular recanalization in patients with symptomatic nonacute intracranial large artery occlusion.

Background: Endovascular recanalization in patients with symptomatic nonacute intracranial large artery occlusion (ILAO) has been reported to be feasible, but technically challenging. This study aimed to determine the predictors of successful endovascular recanalization in patients with symptomatic nonacute ILAO.

Methods: The outcomes of endovascular recanalization attempts performed in 70 consecutive patients showing symptomatic nonacute ILAO with hemodynamic cerebral ischemia between January 2016 to December 2022 were reviewed.

Coralloid WO@covalent organic frameworks S-scheme heterojunction for high efficiency photocatalytic aerobic oxidation.

Reasonably designing and constructing efficient artificial S-mechanism photocatalysts, expanding their application in the field of photocatalytic organic synthesis, have become a hot and challenging topic in the photocatalysis. Herein, a series of coral-like WO@TpPa-H (TpPa-H represents COFs generated by the reaction of 1,3,5-triformylphloroglucinol (Tp) and p-phenylenediamine (Pa-H)) composites were successfully prepared by using a simple in-situ encapsulation strategy. Given the internal electric field at the S-scheme interface, WO acts as an oxidative photocatalyst with sufficient positive valence band (VB) position and TpPa-H as a reductive one with enough negative conduction band (CB) position for the efficient amines oxidative coupling to imines.

Efficient Electrochemical Detection of Hydrogen Peroxide Based on Silver-Centered Preyssler-Type Polyoxometalate Hybrids.

Four polyoxometalate (POM)-based organic-inorganic hybrid compounds, namely, (Hbimb)H[((Mn(HO)(μ-bimb))(Mn(HO))(Mn(HO))(AgPWO))]·29HO (), [(Cu(Hbimb)(HO)(μ-bimb)Cu(Hbimb)(HO))(Cu(HO)(μ-bimb)Cu(HO))((Cu(HO))(μ-bimb)(Cu(HO)))H(AgPWO)]·12.5HO (), (Hbimb)H[(Zn(Hbimb)(HO)(Zn(Hbimb)(HO)))(AgPWO)]·12HO (), and (Hbimb)H[(Ag(HO))(Ag(Hbimb)Ag(Hbimb)(μ-bimb)Ag)(Ag(HO))(AgPWO)]·7HO () (bimb = 1,4-bis(1H-imidazol-1-yl)benzene), were hydrothermally synthesized using a silver-centered Preyssler-type POM K[AgPWO]·18HO (abbreviated as K-{AgPW}) as a precursor. In -, {AgPW} clusters integrating the merits of Ag and {PW} units are modified by different transition metal (TM)-organic fragments to extend the structures into three-dimensional frameworks.

Two-dimensional ultrathin surfactant-encapsulating polyoxometalate assemblies as carriers for monodispersing noble-metal nanoparticles with high catalytic activity and stability.

Noble metal nanoparticles (NMNPs) with excellent catalytic activity and stability play an important role in the field of environmental governance. A uniform distribution and a strong binding force with the carriers of the noble metal nanoparticles are important, but avoidance of the use of additional reducing agents is a promising direction of research. Herein, 2D ultrathin surfactant-encapsulating polyoxometalate (SEP) nanosheets constructed by the self-assembly of dodecyldimethylammonium bromide (DODA) and molybdophosphate (H3PMo12O40, PMo12) are designed to be versatile carriers for Ag nanoparticles.

Endovascular Treatment of Complex Vascular Diseases of the Internal Carotid Artery Using the Willis Covered Stent: Preliminary Experience and Technical Considerations.

The Willis covered stent (WCS) is used to treat complex vascular diseases of the internal carotid artery; however, its performance requires further investigation. This study aimed to present our single-center clinical results and experience of endovascular repair of complex vascular diseases of the internal carotid artery using the WCS. Patients who presented with complex vascular diseases of the internal carotid artery and who were treated with the WCS from December 2013 to September 2018 were retrospectively reviewed.

Construction of the 1D Covalent Organic Framework/2D g-CN Heterojunction with High Apparent Quantum Efficiency at 500 nm.

The reasonable construction of heterojunction photocatalysts with clear nanostructures and a good interface contact especially the one-dimensional/two-dimensional (1D/2D) composite heterojunction with unique morphology is considered one of the most effective strategies for designing highly efficient photocatalysts. Herein, a series of the 1D β-keto-enamine-based covalent organic framework (COF)/2D g-CN composite materials COF-CN (1:; where 1: represents the mass ratio of COF and g-CN, = 2.5, 5, 10, 15, 20) is prepared through the in situ reaction of 2,4,6-triformylphloroglucinol (Tp) and benzidine (BD) in stripped g-CN suspension.

Polyoxometalate-based electron transfer modulation for efficient electrocatalytic carbon dioxide reduction.

The electrocatalytic carbon dioxide (CO) reduction reaction (CORR) involves a variety of electron transfer pathways, resulting in poor reaction selectivity, limiting its use to meet future energy requirements. Polyoxometalates (POMs) can both store and release multiple electrons in the electrochemical process, and this is expected to be an ideal "electron switch" to match with catalytically active species, realize electron transfer modulation and promote the activity and selectivity of the electrocatalytic CORR. Herein, we report a series of new POM-based manganese-carbonyl (MnL) composite CO reduction electrocatalysts, whereby SiW-MnL exhibits the most remarkable activity and selectivity for CORR to CO, resulting in an increase in the faradaic efficiency (FE) from 65% (MnL) to a record-value of 95% in aqueous electrolyte.

Pt-O bond as an active site superior to Pt in hydrogen evolution reaction.

The oxidized platinum (Pt) can exhibit better electrocatalytic activity than metallic Pt in the hydrogen evolution reaction (HER), which has aroused great interest in exploring the role of oxygen in Pt-based catalysts. Herein, we select two structurally well-defined polyoxometalates Na[HPtWO] (PtWO) and NaK[Pt(WO)] (Pt(WO)) as the platinum oxide model to investigate the HER performance. Electrocatalytic experiments show the mass activities of PtWO/C and Pt(WO)/C are 20.

Reduced State of the Graphene Oxide@Polyoxometalate Nanocatalyst Achieving High-Efficiency Nitrogen Fixation under Light Driving Conditions.

The nitrogen (N) reduction to generate ammonia (NH) is a prerequisite for inputting fixed nitrogen (N) into a global biogeochemical cycle. Developing highly efficient photocatalysts for N fixation under mild conditions is still a challenge. Herein, we first report three kinds of reduction states of graphene oxide (GO)@polyoxometalate (POM) composite nanomaterials, which have outstanding photocatalytic N fixation activities in pure water without any other electronic sacrificial agents and cocatalysts at atmospheric pressure and room temperature.

Two-dimensional polyimide heterojunctions for the efficient removal of environmental pollutants under visible-light irradiation.

Two-dimensional (2D) heteromaterials with large interface contact and intimate interfacial charge transition have been considered to be an ideal model for constructing highly efficient photocatalysts. However, few studies have reported on these 2D heterojunctions. Herein, we report a series of new 2D heterojunctions comprising polyimide (PI) and perylene-3,4,9,10-tetracarboxylic dianhydride (TD).

Endovascular recanalization for symptomatic subacute and chronic intracranial large artery occlusion of the anterior circulation: initial experience and technical considerations.

Purpose: This study aimed to report the clinical findings and initial clinical experience of endovascular recanalization for symptomatic subacute/chronic intracranial large artery occlusion (ILAO) of the anterior circulation.

Methods: From October 2015 to December 2017, 13 patients with symptomatic subacute/chronic ILAO of the anterior circulation were enrolled in this study and underwent endovascular recanalization. We collected the initial procedural results, including the rate of successful recanalization and periprocedural complications, and data pertaining to angiographic and clinical follow-up.

A single-center experience in the endovascular treatment of carotid siphon aneurysms using the Willis covered stent: a retrospective analysis.

Objective: To report the clinical results and initial clinical experience of endovascular isolation with the Willis covered stent for carotid siphon aneurysms.

Methods: Between November 2013 and December 2016, a total of 57 patients who presented with carotid siphon aneurysms were treated with the Willis covered stent. Results of the procedures, technical events, and complications were recorded.

MoP/MoC@C: A New Combination of Electrocatalysts for Highly Efficient Hydrogen Evolution over the Entire pH Range.

During the exploration of highly efficient noble-metal-free electrocatalysts for the hydrogen evolution reaction (HER), a promising and challenging strategy is to fabricate composite nanocatalysts by finely tuning metal and/or nonmetal element components. Herein, we report a new HER electrocatalyst, which is composed of molybdenum phosphide and molybdenum carbide composite nanoparticles (NPs) coated by few-layer N-doped graphitic carbon shells (denoted as MoP/MoC@C). Such a new combination mode of electrocatalysts is realized by a one-step annealing route with the mixture of a Mo/P-based polyoxometalate (POM) and dicyandiamide.

Ag/AgHPMoO Nanowires with Enhanced Visible-Light-Driven Photocatalytic Performance.

Photocatalysis, a promising technology platform to address the environmental problems, has been attracting considerable attention. In this paper, Ag/AgHPMoO (simplified as Ag/AgHPMo) nanowires have been synthesized by a facile solid reaction route and in situ photodeposited method. The results of SEM and TEM indicate that the diameters of AgHPMo nanowires are about 45 ± 10 nm, and Ag nanoparticles with diameters in the range of 5-15 nm are uniformly anchored on the surface of AgHPMo nanowires.

Endovascular isolation of intracranial blood blister-like aneurysms with Willis covered stent.

Objective: Intracranial blood blister-like aneurysm (BBA) is a rare type of aneurysm that lacks all layers of the arterial wall. These fragile aneurysms have the propensity to rupture with minimal manipulation, which makes them hazardous and difficult to treat. The present study evaluated the safety and feasibility of endovascular treatment of BBAs with the Willis covered stent.

A Surfactant-Encapsulating Polyoxometalate Nanowire Assembly as a New Carrier for Nanoscale Noble-Metal Catalysts.

The loading of noble-metal nanoparticles (NMNPs) onto various carriers to obtain stable and highly efficient catalysts is currently an important strategy in the development of noble metal (NM)-based catalytic reactions and their applications. We herein report a nanowire supramolecular assembly constructed from the surfactant-encapsulating polyoxometalates (SEPs) CTAB-PW , which can act as new carriers for NMNPs. In this case, the Ag NPs are loaded onto the SEP nanowire assembly with a narrow size distribution from 5 to 20 nm in diameter; the average size is approximately 10 nm.

Highly Dispersed Polyoxometalate-Doped Porous Co O Water Oxidation Photocatalysts Derived from POM@MOF Crystalline Materials.

Rational design of earth-abundant photocatalysts is an important issue for solar energy conversion and storage. Polyoxometalate (POM)@Co O composites doped with highly dispersive molecular metal-oxo clusters, synthesized by loading a single Keggin-type POM cluster into each confined space of a metal-organic framework (MOF), exhibit significantly improved photocatalytic activity in water oxidation compared to the pure MOF-derived nanostructure. The systematic synthesis of these composite nanocrystals allows the conditions to be tuned, and their respective water oxidation catalytic performance can be efficiently adjusted by varying the thermal treatment temperature and the feeding amount of the POM.

Black-colored ZnO nanowires with enhanced photocatalytic hydrogen evolution.

Black-colored ZnO nanowires have been prepared in a metal-organic chemical vapor deposition system by employing a relatively low growth temperature and oxygen-deficient conditions. X-ray photoelectron spectroscopy reveals the incorporation of carbon into the nanowires. The photocatalytic hydrogen evolution activity of the black-colored ZnO nanowires is over 2.

Cationic Covalent Organic Frameworks: A Simple Platform of Anionic Exchange for Porosity Tuning and Proton Conduction.

Mimicking proton conduction mechanism of Nafion to construct novel proton-conducting materials with low cost and high proton conductivity is of wide interest. Herein, we have designed and synthesized a cationic covalent organic framework with high thermal and chemical stability by combining a cationic monomer, ethidium bromide (EB) (3,8-diamino-5-ethyl-6-phenylphenanthridinium bromide), with 1,3,5-triformylphloroglucinol (TFP) in Schiff base reactions. This is the first time that the stable cationic crystalline frameworks allowed for the fabrication of a series of charged COFs (EB-COF:X, X = F, Cl, Br, I) through ion exchange processes.

Hybrid Coordination Networks Constructed from ɛ-Keggin-Type Polyoxometalates and Rigid Imidazole-Based Bridging Ligands as New Carriers for Noble-Metal Catalysts.

Three hybrid coordination networks that were constructed from ɛ-Keggin polyoxometalate building units and imidazole-based bridging ligands were prepared under hydrothermal conditions, that is, H[(Hbimb)2 (bimb){Zn4 PMo(V8) Mo(VI) 4O40}]⋅6 H2O(1), [Zn(Hbimbp)(bimbp)3 {Zn4 PMo(V8) Mo(VI) 4O40}]⋅DMF⋅3.5 H2O(2), and H[Zn2 (timb)2 (bimba)2 Cl2 {Zn4 PMo(V8) Mo(VI) 4O40}]⋅7 H2O(3) (bimb=1,4-bis(1-imidazolyl)benzene, bimbp=4,4'-bis(imidazolyl)biphenyl, timb=1,3,5-tris(1-imidazolyl)benzene, bimba=3,5-bis(1-imidazolyl)benzenamine). All three compounds were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction.