Visible‐light‐driven photoreduction of CO2 to energy‐rich chemicals in the presence of H2O without any sacrifice reagent is of significance, but challenging. Herein, Eosin Y‐functionalized porous polymers (PEosinY‐N, N=1–3), with high surface areas up to 610 m2 g−1, are reported. They exhibit high activity for the photocatalytic reduction of CO2 to CO in the presence of gaseous H2O, without any photosensitizer or sacrifice reagent, and under visible‐light irradiation. Especially, PEosinY‐1 derived from coupling of Eosin Y with 1,4‐diethynylbenzene shows the best performance for the CO2 photoreduction, affording CO as the sole carbonaceous product with a production rate of 33 μmol g−1 h−1 and a selectivity of 92 %. This work provides new insight for designing and fabricating photocatalytically active polymers with high efficiency for solar‐energy conversion.

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Single-atom metal catalysts (SAMCs) have high catalytic activity, but mass production of SAMCs with high metal loading remains challenging. In this work, a two-step and one-pot strategy is presented to prepare mesoporous carbon nitride (CN)-based Cu single-atom catalysts (Cu–CN-x, where x refers to the metal loading in wt %) with ultrahigh metal loadings (e.g., up to 26.6 wt %), in which the mixture of urea and copper chloride is first heated at 180 °C and then calcined at 550 °C. Extended X-ray absorption fine structure analysis demonstrates that a Cu single atom is doped into the skeleton of CN via replacing one carbon atom and bonding with three nitrogen atoms. The resultant Cu–CN-x catalyst displays excellent performance and high stability for catalyzing the reaction of terminal alkynes with atmospheric carbon dioxide, much better than the best reported catalyst, synergistically attributed to both the isolated Cu single atom and porous structure of the support. Density functional theory calculation shows that the reaction between CO2 and deprotonated phenylacetylene is energetically exothermic on Cu–CN with a reaction energy of about −0.27 eV and an energy barrier of +0.85 eV. This synthetic strategy paves a universal way for mass production of SAMCs with high-density metal loadings.

A highly efficient Co-based catalytic system, composed of a commercially available Co salt, a tetradentate phosphine ligand P(CHCHPPh)(PP), and a base (denoted as [Co]/PP/base), is developed for the methylation of C(sp)-H and C(sp)-H bonds using methanol as a methylating reagent. The Co(BF)·6HO/PP/KCO catalytic system showed high catalytic activity for the methylation of C-H bonds in aryl alkyl ketones, aryl acetonitriles, and indoles, with wide substrate scope and good functional group tolerance, and methyl-substituted products were obtained in good to excellent yields at 100 °C. This cheap, readily available, and highly efficient Co-based catalytic system may have promising applications in methylation reaction using methanol.

The methylation of amines using methanol is a promising route to synthesize N-methylamines, and the development of cheap and efficient catalytic system for this reaction is of great significance. Herein, we reported a cobalt (Co)based catalytic system, which was in situ formed from commercially available Co precursor and a tetradentate phosphine ligand P(CH 2 CH 2 PPh 2 ) 3 combined with K 3 PO 4 . This catalystic system was very effective for the selective production of dimethylated products from aliphatic amines and monomethylated ones from aromatic amines. The reaction mechanism was further investigated by control and isotope labelling experiments.

Radical reaction: A convenient synthesis of hydroxyl isoindolones by a Pd-catalyzed CH activation/annulation reaction with near "click chemistry" efficiency is presented (see scheme; TBHP=tert-butyl hydrogen peroxide). This methodology features short reaction times (10-30 min), high atom economy, wide substrate scope (22 examples), and good reaction yields (up to 93 %).

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The biological pretreatment of lignocellulosic biomass is a low-cost and eco-friendly method for facilitating enzymatic hydrolysis. In this study, strains with lignin depletion capability were screened using a high-throughput screening method. Sixty-three strains were screened out and Myrothecium verrucaria secreted three lignin-degrading enzymes simultaneously during the bio-pretreatment process. The activity levels of laccase, lignin peroxidase and manganese peroxidase were 6.61, 0.78 and 1.31 U g−1 dry biomass. The content of lignin in corn stover decreased by 42.30% after bio-pretreatment, and the conversion rate increased by 123.84% during the subsequent saccharification process in comparison with the untreated corn stover. Furthermore, the effects of bio-pretreatment on the structure of corn stover were presented using a scanning electron microscope (SEM), Brunauer-Emmet-Teller (BET), X-ray diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR). The results showed that M.V. is a promising lignin-degrading fungus. This research demonstrated an efficient pretreatment approach for enhancing the enzymatic saccharification of corn stover.