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Cometabolic degradation is currently an effective and extensively way to remove high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs). Unfortunately, due to low bio-accessibility and high biotoxicity, the cometabolic degradation rate of HMW-PAHs is limited. Glycine-β-cyclodextrin (GCD) was obtained through amino modification of β-cyclodextrin (BCD) and added to cometabolic system of phenanthrene (PHE) and pyrene (PYR) to assist PYR biodegradation. Results show that the addition of GCD (100 mg/L) effectively improved the removal rate of PYR (20 mg/L) by 42.3%. GCD appeared to increase the bio-accessibility and reduce the biotoxicity of PHE and PYR, and then promoted the growth of Pseudomonas stutzeri DJP1 and stimulated the elevation of dehydrogenase (DHA) and catechol 12 dioxygenase (C12O) activities. The phthalate metabolic pathway was accelerated, which improved the cometabolic degradation. This study provided a new reference for the cometabolic degradation of HMW-PAHs. [ABSTRACT FROM AUTHOR]

At present, cometabolic degradation is an extensive method for the biological removal of high molecular weight polycyclic aromatic hydrocarbons (HMW-PAHs) in the marine environment. However, due to the refractory to degradation and high toxicity, there are few studies on pyrene (PYR) cometabolic degradation with phenanthrene (PHE) as substrate. In this study, a Pseudomonas stutzeri DJP1 strain isolated from sediments was used in the cometabolic system of PHE and PYR. The biomass and the activity of key enzymes such as dehydrogenase and catechol 12 dioxygenase of strain were improved, but the enhancement of biotoxicity resulted in the inhibition of cometabolism simultaneously. Seven metabolites were identified respectively in PYR, PHE degradation cultures. It was speculated that the cometabolism of PHE and PYR had a common phthalic acid pathway, and the degradation pathway of PHE was included in the downstream pathway of PYR. The functional genes such as PhdF, NidD and CatA involved in DJP1 degradation were revealed by Genome analysis. This study provides a reference for the biodegradation of PYR and PHE in real marine environment. [ABSTRACT FROM AUTHOR]

Electrocatalytic materials are a critical bottleneck for the development of new energy economics. This review summarizes the unique physicochemical properties of topological, magnetic, and rare earth materials and their applications in the functionalization of electrocatalysts. Topological materials have unique band structures and geometric structures, and the interface difference in charge transport structures can give rise to topological insulators, topological superconductors, and Dirac metals. Magnetic materials possess distinctive electron spin-splitting configurations, and varying spin strengths induce disparate impacts on the intermediate equilibrium adsorption capability. Rare earth materials have unique f-electron roaming properties, broad atomic radius, and f-orbital configurations, which typically confer notable advantages in oxygen reduction reactions. Furthermore, the catalytic performance exhibits significant differences under an external alternating electric, thermal, and magnetic field. These new materials show great potential in the re-functionalization of electrocatalytic materials and are expected to lead the development of the next generation of emerging energy materials. [ABSTRACT FROM AUTHOR]

Carbon monoxide electroreduction (COER) has been a key part of tandem electrolysis of carbon dioxide (CO2), in which searching for high catalytic performance COER electrocatalysts remains a great challenge. Herein, by means of density functional theory (DFT) computations, we explored the potential of a series of transition metal atoms anchored on N-doped γ-graphyne (TM@N-GY, TM from Ti to Au) as the COER electrocatalysts. We found that the final product selectivity of these single-atom catalysts depended on the position of the metal atom in the periodic table, with metals in the front and middle of each periodic period exhibiting high selectivity for CH4, while metals in the back producing CH3OH. Machine learning (ML) found that metal atomic number was intrinsic to the difference in COER performance of these single-atom catalysts (SACs). The free energy changes showed that Mn@N-GY and Ni@N-GY exhibited outstanding COER catalytic performance for producing CH4 and CH3OH, respectively. Our results provide theoretical and experimental guidance for designing efficient COER catalysts to generate C1 products. [ABSTRACT FROM AUTHOR]

Modulation of the surface electron distribution is a challenging problem that determines the adsorption ability of catalytic process. Here, we address this challenge by bridging the inner and outer layers of the core—shell structure through the bridge Br atom. Carbon shell wrapped copper bromide nanorods (CuBr@C) are constructed for the first time by chemical vapour deposition with hexabromobenzene (HBB). HBB pyrolysis provides both bridge Br atom and C shells. The C shell protects the stability of the internal halide structure, while the bridge Br atom triggers the rearrangement of the surface electrons and exhibits excellent electrocatalytic activity. Impressively, the hydrogen evolution reaction (HER) activity of CuBr@C is significantly better than that of commercial N-doped carbon nanotubes, surpassing commercial Pt/C at over 200 mA·cm−2. Density functional theory (DFT) calculations reveal that bridge Br atoms inspire aggregation of delocalized electrons on C-shell surfaces, leading to optimization of hydrogen adsorption energy. [ABSTRACT FROM AUTHOR]