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Owing to the easy over-oxidation, it is a promising yet challenging task to explore renewable carbon resources to control the sunlight-driven selective catalytic oxidation of biomass-derived 5-hydroxymethylfurfural (HMF), producing important chemical feedstocks, namely, less-oxidized 2,5-diformylfuran (DFF) and 5-hydroxymethyl-2-furancarboxylic acid (HMFCA). Herein, we have developed a photocatalyst by anchoring a Ru complex on CdS quantum dots, which achieves selective oxidation of HMF toward DFF or HMFCA with high conversion (81 %) and selectivity (90 %), based on the controllable generation of two oxygen radicals under different atmospheres. Such selective conversion can also work well outside the laboratory by using natural sunlight. In particular, the selective production of HMFCA through photocatalytic HMF oxidation is achieved for the first time. More importantly, our photocatalyst is applicable for the selective oxidation of other compounds with hydroxyl and aldehyde groups.

The effect of surface tensile strain on the photocatalysis is an open question. In this work, strain engineering has been demonstrated to promote the performance of photocatalysis by curved 2D mate...

Photocatalysis under mild conditions is an intriguing avenue for organic chemical manufacturing to confront the serious fossil energy crisis. Herein, we report a direct light-driven alkene production through alcohol dehydration, using nonstoichiometric tungsten oxide of W

The design of efficient and stable photocatalysts for robust CO2 reduction without sacrifice reagent or extra photosensitizer is still challenging. Herein, a single-atom catalyst of isolated single atom cobalt incorporated into Bi3O4Br atomic layers is successfully prepared. The cobalt single atoms in the Bi3O4Br favors the charge transition, carrier separation, CO2 adsorption and activation. It can lower the CO2 activation energy barrier through stabilizing the COOH* intermediates and tune the rate-limiting step from the formation of adsorbed intermediate COOH* to be CO* desorption. Taking advantage of cobalt single atoms and two-dimensional ultrathin Bi3O4Br atomic layers, the optimized catalyst can perform light-driven CO2 reduction with a selective CO formation rate of 107.1 µmol g−1 h−1, roughly 4 and 32 times higher than that of atomic layer Bi3O4Br and bulk Bi3O4Br, respectively.

Solar-driven reduction of CO2 , which converts inexhaustible solar energy into value-added fuels, has been recognized as a promising sustainable energy conversion technology. However, the overall conversion efficiency is significantly limited by the inefficient charge separation and sluggish interfacial reaction dynamics, which resulted from a lack of sufficient active sites. Herein, Bi12 O17 Cl2 superfine nanotubes with a bilayer thickness of the tube wall are designed to achieve structural distortion for the creation of surface oxygen defects, thus accelerating the carrier migration and facilitating CO2 activation. Without cocatalyst and sacrificing reagent, Bi12 O17 Cl2 nanotubes deliver high selectivity CO evolution rate of 48.6 μmol g-1 h-1 in water (16.8 times than of bulk Bi12 O17 Cl2 ), while maintaining stability even after 12 h of testing. This paves the way to design efficient photocatalysts with collaborative optimizing charge separation and CO2 activation towards CO2 photoreduction.

BACKGROUND Fusarium graminearum is the main pathogen of Fusarium Head Blight (FHB), a worldwide plant disease and one of the major wheat diseases in China. The control of the FHB is mainly dependent on the application of DMIs fungicides. Fungal sterol 14α-demethylase enzymes (CYP51) are the main target for DMIs fungicides. In order to investigate the binding mechanism between azoles and CYP51B in F.graminearum, the molecular modeling study and biological evaluation were performed. RESULTS Firstly, the homology model based on the crystal structure of Aspergillus fumigatus was built. Secondly, molecular docking and molecular dynamics (MD) simulation were used to identify the optimum binding mode between Propiconazole (PRP), Diniconazole (DIN), Triadimenol (TRL), Tebuconazole (TEC), and Triadimefon (TRN) with FgCYP51B. Furthermore, binding free energy of the five protein-inhibitor complexes was calculated by Molecular Mechanics Generalized Born Surface Area and Poisson–Boltzmann Surface Area (MM-GB/PBSA) methods. The key residues to the selective binding of azoles to FgCYP51B were recognized by per-residue free energy decomposition analysis. The five ligands have similar binding mode in the active pocket. Inhibitors PRP and TEC have more beneficial binding free energy to the enzyme than TRN, TRL and DIN. Furthermore, the Amino acid residues Phe511, Val136, Ile374, Ala308, Ser312 and Try137 of FgCYP51B are the key residues interacting with azoles fungicides. The EC50 value of PRP, TEC, DIN, TRL and TRN is 0.024, 0.047, 0.148, 0.154 and 0.474 mg/L according to the experimental evaluation, respectively. These five molecules exhibited potential inhibitory activity against CYP51B protein from the F. graminearum. CONCLUSION The results suggest that azoles fungicides for FgCYP51B should possess more hydrophobic groups interacting with residues Phe511, Val136, Ile374, Ala308, Ser312 and Tyr137. PRP and TEC should be preferred to control Fusarium Head Blight disease than DIN, TRL and TRN.

Photocatalytic CO2 reduction has been regarded as an appealing pathway for CO2 conversion to hydrocarbon fuels. To boost the CO2 photoreduction performance, developing suitable cocatalyst on the photocatalysts is an efficient strategy. Herein, Co2N is employed as novel noble-metal-free cocatalyst to promote the CO2 photoreduction performance of BiOBr ultrathin nanosheets. The optimal Co2N/BiOBr delivers a high selectivity CO formation rate of 67.8 µmol g−1 h−1 in pure water without sacrificial reagent or extra photosensitizer, roughly 6 times higher than BiOBr. Co2N can create strong electronic interactions with BiOBr, steering the electron transfer from BiOBr, across the interface to metallic Co2N and finally to the surface. Apart from the charge separation steering, the activation energy barrier can be lowered on Co2N surface via stabilize COOH* intermediates, tuning the rate-limiting step from the formation of COOH* on BiOBr to the formation of CO* on Co2N, jointly optimize the CO2 photoreduction activity. This strategy affords an accessible pathway for designing cocatalysts for efficient CO2 photoreduction.

Photocatalytic CO2 reduction suffers from the weakness of high energy barrier, low efficiency and poor selectivity. Exploring effective strategy to enhance the adsorption and activation behavior of CO2 molecules is an alternative approach to boost CO2 photoreduction performance. In this work, abundant oxygen vacancies (VO) are introduced onto Bi2Sn2O7 nanoparticles (NPs) by decreasing their size down to about 4 nm. The VO mediated NPs exhibit a tremendous 8.1 times enhanced performance than the bulk counterpart towards CO2-to−CO conversion in pure water. This is attributed to fast charge diffusion and abundant Vo for effective CO2 adsorption and activation in the ultra-small nanoparticles. The VO mediated Bi2Sn2O7 NPs have electron back donation nature and optimized electronic structure for effectively activating CO2, which were demonstrated by density functional theory calculations. During the reduction process, the Vo can effeciently stabilize the COOH* intermediates, and also lower the energy barrier of CO desorption determining step.

The design of efficient and stable photocatalysts for robust CO2 reduction without sacrifice reagent or extra photosensitizer is still challenging. Herein, a single-atom catalyst of isolated single atom cobalt incorporated into Bi3O4Br atomic layers is successfully prepared. The cobalt single atoms in the Bi3O4Br favors the charge transition, carrier separation, CO2 adsorption and activation. It can lower the CO2 activation energy barrier through stabilizing the COOH* intermediates and tune the rate-limiting step from the formation of adsorbed intermediate COOH* to be CO* desorption. Taking advantage of cobalt single atoms and two-dimensional ultrathin Bi3O4Br atomic layers, the optimized catalyst can perform light-driven CO2 reduction with a selective CO formation rate of 107.1 µmol g−1 h−1, roughly 4 and 32 times higher than that of atomic layer Bi3O4Br and bulk Bi3O4Br, respectively., While the conversion of CO2 to high-value products provides a promising means to remove and utilize atmospheric carbon, few materials can do so without wasteful, sacrificial reagents. Here, authors prepare single-atom Co on Bi3O4Br nanosheets as CO2 reduction catalysts using water and light.

Fusarium graminearum is the main pathogen of Fusarium head blight (FHB), a worldwide plant disease and a major disease of wheat in China. Control of FHB is mainly dependent on the application of demethylase inhibitor (DMI) fungicides. Fungal sterol 14α-demethylase enzymes (CYP51) are the main target for DMI fungicides. A molecular modeling study and biological evaluation were performed to investigate the binding mechanism between azoles and CYP51B in F. graminearum.A homology model based on the crystal structure of Aspergillus fumigatus was built. Molecular docking and molecular dynamics (MD) simulations were then used to identify the optimum binding mode of propiconazole (PRP), diniconazole (DIN), triadimenol (TRL), tebuconazole (TEC) and triadimefon (TRN) with FgCYP51B. Furthermore, the binding free energy of the five protein-inhibitor complexes was calculated using molecular mechanics generalized Born surface area and Poisson-Boltzmann surface area (MM-GB/PBSA) methods. Key residues in the selective binding of azoles to FgCYP51B were recognized by per-residue free energy decomposition analysis. The five ligands have a similar binding mode in the active pocket. The binding free energy to the enzyme for inhibitors PRP and TEC is more favorable than that of TRN, TRL and DIN. Furthermore, the amino acid residues Phe511, Val136, Ile374, Ala308, Ser312 and Try137 of FgCYP51B are key residues interacting with azoles fungicides. From the experimental evaluation, the 50% effective concentration (ECAzole fungicides for FgCYP51B should possess more hydrophobic groups interacting with residues Phe511, Val136, Ile374, Ala308, Ser312 and Tyr137. PRP and TEC are preferable for the control of FHB than DIN, TRL and TRN. © 2017 Society of Chemical Industry.