Pd-Catalyzed Carbonylative Synthesis of 4H-Benzo[d][1,3]Oxazin-4-Ones Using Benzene-1,3,5-Triyl Triformate as the CO Source.

A facile synthesis of 4H-benzo[d][1,3]oxazin-4-one derivatives by Pd-catalyzed carbonylative cross-coupling between N-(ortho-bromoaryl)amides and benzene-1,3,5-triyl triformate (TFBen) was developed. This procedure does not require the toxic and flammable gas CO as the carbonyl source and tolerates a wide scope of functional groups. Remarkably, 4H-benzo[d][1,3]oxazin-4-ones incorporated to natural products and drugs can be constructed by this method.

Highly Stable Layered Coordination Polymer Electrocatalyst toward Efficient CO2 -to-CH4 Conversion.

Cu2+ -based materials, a class of promising catalysts for the electrocatalytic carbon dioxide reduction reaction (CO2 RR) to value-added chemicals, usually undergo inevitable and uncontrollable reorganization processes during the reaction, resulting in catalyst deactivation or the new active sites formation and bringing great challenges to exploring their structure-performance relationships. Herein, a facile strategy is reported for constructing Cu2+ and 3, 4-ethylenedioxythiophene (EDOT) coordination to stabilize Cu2+ ions to prepare a novel layered coordination polymer (CuPEDOT). CuPEDOT enables selective reduction of CO2 to CH4 with 62.7% Faradaic efficiency at the current density of 354 mA cm-2 in a flow cell, and the catalyst is stable for at least 15 h. In situ spectroscopic characterization and theoretical calculations reveal that CuPEDOT catalyst can maintain the Cu2+ -EDOT coordination structurally stable in CO2 RR and significantly promote the further hydrogenation of *CO intermediates, favoring the formation of CH4 instead of dimerization to C2 products. The strong coordination between EDOT and Cu2+ prevents the reduction of Cu2+ ions during CO2 RR. The finding of this work provides a new perspective on designing molecularly stable, highly active catalysts for CO2 RR.

Ultra-fast synthesis of three-dimensional porous Cu/Zn heterostructures for enhanced carbon dioxide electroreduction.

The construction of metal hetero-interfaces has great potential in the application of electro-catalytic carbon dioxide reduction (ECR). Herein, we report a fast, efficient, and simple electrodeposition strategy for synthesizing three-dimensional (3D) porous Cu/Zn heterostructures using the hydrogen bubble template method. When the deposition was carried out at -1.0 A for 30 s, the obtained 3D porous Cu/Zn heterostructures on carbon paper (CP) demonstrated a nearly 100% CO faradaic efficiency (FE) with a high partial current density of 91.8 mA cm-2 at -2.1 V vs. Ag/Ag+ in the mixed electrolyte of ionic liquids/acetonitrile in an H-type cell. In particular, the partial current density of CO could reach 165.5 mA cm-2 and the FE of CO could remain as high as 94.3% at -2.5 V vs. Ag/Ag+. The current density is much higher than most reported to date in an H-type cell (Table S1). Experimental and density functional theory (DFT) calculations reveal that the outstanding electrocatalytic performance of the electrode can be ascribed to the formation of 3D porous Cu/Zn heterostructures, in which the porous and self-supported architecture facilitates diffusion and the Cu/Zn heterostructures can reduce the energy barrier for ECR to CO.

[Treatment Effects of Earthworm Constructed Wetlands in Different Working Conditions].

The feasibility of a new sludge treatment technology of earthworm constructed wetlands was tested by adding earthworm into the traditional sludge dying reed beds. The dewatering and stabilization effects of the upper layer sludge were tested under different sludge loading rates of 48, 65, 80 kg·(m2·a)-1, different earthworm stocking densities of 0, 0.43, 0.54, 0.65 kg·m-2 and different sludge loading frequencies. The results indicated that it was feasible to provide a shelter for earthworm during the loading period by setting a damper with a buried depth of 10 mm. The addition of earthworm could effectively improve the dewatering and stabilization effects of earthworm constructed wetlands, by lowering the DHA and decreasing the moisture content and VS of sludge by 15% and 10% respectively. The stabilization effects of earthworm constructed wetlands reached the best under the stocking density of 0.65 kg·m-2. With the increase of sludge loading rate and decrease of loading frequency, the running efficiency of earthworm constructed wetlands would be worse.