Effects of Stephania hainanensis alkaloids on MSU-induced acute gouty arthritis in mice.

Background: Gout is initiated by the precipitation of monosodium urate (MSU) crystals within the joints and soft tissues, and it can eventually cause acute or chronic arthritis. MSU crystals trigger, amplify, and maintain a strong inflammatory response through promoting proinflammatory activity. In this study, the therapeutic effects of Stephania hainanensis (S.

Bioinspired metal complexes for energy-related photocatalytic small molecule transformation.

Bioinspired transformation of small-molecules to energy-related feedstocks is an attractive research area to overcome both the environmental issues and the depletion of fossil fuels. The highly effective metalloenzymes in nature provide blueprints for the utilization of bioinspired metal complexes for artificial photosynthesis. Through simpler structural and functional mimics, the representative herein is the pivotal development of several critical small molecule conversions catalyzed by metal complexes, e.

Thiol Activation toward Selective Thiolation of Aromatic C-H Bond.

Direct C-S bond coupling is an attractive way to construct aryl sulfur ether, a building block for a variety of biological active molecules. Herein, we disclose an effective model for regioselective thiolation of the aromatic C-H bond by thiol activation instead of arene activation. Strikingly, this method has been applied into anisole derivatives that are not available in the arene activation approach to forge a single thioether isomer with high reactivity.

Photoelectrochemical cell for P-H/C-H cross-coupling with hydrogen evolution.

Photoelectrochemistry enables the formation of a variety of active intermediates for organic synthesis in an environmentally friendly manner. Herein, a photoelectrochemical cell is fabricated to realize activation of P-H/C-H bonds for cross-coupling hydrogen evolution. As compared with an electrochemical cell, nearly 90% external bias input is saved to drive the C-P bond construction with good to excellent yields.

Regioselective Amination of an Aromatic C-H Bond by Trifluoroacetic Acid via Electrochemistry.

A trifluoroacetic acid-facilitated amination of alkoxyl arene has been established via anodic oxidation in an undivided cell. In the absence of any additional metal or oxidant reagents, a series of aromatic and heteroaromatic amine derivatives have been synthesized in good to excellent yields. Our findings reveal the possibility of achieving complete -selective amination of a simple arene, which emerges as an efficient route for facile and large-scale organic synthesis.

Semiconductor Quantum Dots: An Emerging Candidate for CO Photoreduction.

As one of the most critical approaches to resolve the energy crisis and environmental concerns, carbon dioxide (CO ) photoreduction into value-added chemicals and solar fuels (for example, CO, HCOOH, CH OH, CH ) has attracted more and more attention. In nature, photosynthetic organisms effectively convert CO and H O to carbohydrates and oxygen (O ) using sunlight, which has inspired the development of low-cost, stable, and effective artificial photocatalysts for CO photoreduction. Due to their low cost, facile synthesis, excellent light harvesting, multiple exciton generation, feasible charge-carrier regulation, and abundant surface sites, semiconductor quantum dots (QDs) have recently been identified as one of the most promising materials for establishing highly efficient artificial photosystems.

Recent Advances in Sensitized Photocathodes: From Molecular Dyes to Semiconducting Quantum Dots.

The increasing demand for sustainable and environmentally benign energy has stimulated intense research to establish highly efficient photo-electrochemical (PEC) cells for direct solar-to-fuel conversion via water splitting. Light absorption, as the initial step of the catalytic process, is regarded as the foundation of establishing highly efficient PEC systems. To make full use of visible light, sensitization on photoelectrodes using either molecular dyes or semiconducting quantum dots provides a promising method.

Eosin Y as a Direct Hydrogen-Atom Transfer Photocatalyst for the Functionalization of C-H Bonds.

Eosin Y, a well-known economical alternative to metal catalysts in visible-light-driven single-electron transfer-based organic transformations, can behave as an effective direct hydrogen-atom transfer catalyst for C-H activation. Using the alkylation of C-H bonds with electron-deficient alkenes as a model study revealed an extremely broad substrate scope, enabling easy access to a variety of important synthons. This eosin Y-based photocatalytic hydrogen-atom transfer strategy is promising for diverse functionalization of a wide range of native C-H bonds in a green and sustainable manner.

Self-assembled inorganic clusters of semiconducting quantum dots for effective solar hydrogen evolution.

Owing to promoted electron-hole separation, the catalytic activity of semiconducting quantum dots (QDs) towards solar hydrogen (H2) production has been significantly enhanced by forming self-assembled clusters with ZnSe QDs made ex situ. Taking advantage of the favored interparticle hole transfer to ZnSe QDs, the rate of solar H2 evolution of CdSe QDs can be increased to ∼30 000 μmol h-1 g-1 with ascorbic acid as the sacrificial reagent, ∼150-fold higher than that of bare CdSe QDs clusters under the same conditions.

Enhanced Charge Separation Efficiency Accelerates Hydrogen Evolution from Water of Carbon Nitride and 3,4,9,10-Perylene-tetracarboxylic Dianhydride Composite Photocatalyst.

The catalytic ability of graphitic carbon nitride is greatly affected by its intrinsic electronic properties. Although combination with chromophore has been demonstrated to be one of the promising approaches to improve the catalytic performance of carbon nitride, it is imperative to understand the key factors governing the whole process. Here, we report a composite photocatalyst CN-P by embedding perylene unit into the matrix of carbon nitride.

Three-Dimensional Graphene Networks with Abundant Sharp Edge Sites for Efficient Electrocatalytic Hydrogen Evolution.

To achieve sustainable production of hydrogen (H ) through water splitting, establishing efficient and earth-abundant electrocatalysts is of great necessity. Morphology engineering of graphene is now shown to modulate the electronic structure of carbon skeleton and in turn endow it with excellent ability of proton reduction. Three-dimensional (3D) graphene networks with a high density of sharp edge sites are synthesized.

Assembling metallic 1T-MoS nanosheets with inorganic-ligand stabilized quantum dots for exceptional solar hydrogen evolution.

Due to their enhanced light harvesting, favored interfacial charge transfer and excellent proton reduction activity, hybrid photocatalysts of metallic 1T-MoS nanosheets and inorganic-ligand stabilized CdSe/ZnS QDs obtained via a self-assembly approach can produce H gas with a rate of ∼155 ± 3.5 μmol h mg under visible-light irradiation (λ = 410 nm), the most exceptional performance of solar H evolution using MoS as a cocatalyst known to date.

Self-Assembled Framework Enhances Electronic Communication of Ultrasmall-Sized Nanoparticles for Exceptional Solar Hydrogen Evolution.

Colloidal quantum dots (QDs) have demonstrated great promise in artificial photosynthesis. However, the ultrasmall size hinders its controllable and effective interaction with cocatalysts. To improve the poor interparticle electronic communication between free QD and cocatalyst, we design here a self-assembled architecture of nanoparticles, QDs and Pt nanoparticles, simply jointed together by molecular polyacrylate to greatly enhance the rate and efficiency of interfacial electron transfer (ET).

Hole-Accepting-Ligand-Modified CdSe QDs for Dramatic Enhancement of Photocatalytic and Photoelectrochemical Hydrogen Evolution by Solar Energy.

can be significantly enhanced simply by introducing a suitable hole-accepting-ligand for achieving efficient hole extraction and transfer at the nanoscale interfaces, which opens an effective pathway for dissociation of excitons to generate long-lived charge separation, thus improving the solar-to-fuel conversion efficiency.

Secondary coordination sphere accelerates hole transfer for enhanced hydrogen photogeneration from [FeFe]-hydrogenase mimic and CdSe QDs in water.

Achieving highly efficient hydrogen (H2) evolution via artificial photosynthesis is a great ambition pursued by scientists in recent decades because H2 has high specific enthalpy of combustion and benign combustion product. [FeFe]-Hydrogenase ([FeFe]-H2ase) mimics have been demonstrated to be promising catalysts for H2 photoproduction. However, the efficient photocatalytic H2 generation system, consisting of PAA-g-Fe2S2, CdSe QDs and H2A, suffered from low stability, probably due to the hole accumulation induced photooxidation of CdSe QDs and the subsequent crash of [FeFe]-H2ase mimics.

Improved Photoelectrocatalytic Performance for Water Oxidation by Earth-Abundant Cobalt Molecular Porphyrin Complex-Integrated BiVO4 Photoanode.

An earth-abundant, low-cost cobalt porphyrin complex (CoTCPP) is designed as a molecular catalyst to work on three-dimensional BiVO4 film electrode for water oxidation for the first time. Under illumination of a 100 mW cm(-2) Xe lamp, the CoTCPP-functionalized BiVO4 photoanode exhibits a 2-fold enhancement in photocurrent density at 1.23 V vs RHE and nearly a 450 mV cathodic shift at 0.