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Rational modulation of surface reconstruction in the oxygen evolution reaction (OER) utilizing defect engineering to form efficient catalytic activity centers is a topical interest in the field of catalysis. The introduction of point defects has been demonstrated to be an effective strategy to regulate the electronic configuration of electrocatalysts, but the influence of more complex planar defects (e.g., twins and stacking faults), on their intrinsic activity is still not fully understood. This study harnesses ultrasonic cavitation for rapid and controlled introduction of different types of defects in the FeCoNi/FeAl2O4 hybrid coating, optimizing OER catalytic activity. Theoretical calculations and experiments demonstrate that the different defects optimize the coordination environment and facilitate the activation of surface reconstruction into true catalytic activity centers at lower potentials. Moreover, it demonstrates exceptional durability, maintaining stable oxygen production at a high current density of 300 mA cm−2 for over 120 hours. This work not only presents a novel pathway for designing advanced electrocatalysts but also deepens our understanding of defect‐engineered catalytic mechanisms, showcasing the potential for rapid and efficient enhancement of electrocatalytic performance. [ABSTRACT FROM AUTHOR]

Waste plastics represent major environmental and economic burdens due to their ubiquity, slow breakdown rates, and inadequacy of current recycling routes. Polyethylenes are particularly problematic, because they lack robust recycling approaches despite being the most abundant plastics in use today. We report a novel chemical and biological approach for the rapid conversion of polyethylenes into structurally complex and pharmacologically active compounds. We present conditions for aerobic, catalytic digestion of polyethylenes collected from post‐consumer and oceanic waste streams, creating carboxylic diacids that can then be used as a carbon source by the fungus Aspergillus nidulans. As a proof of principle, we have engineered strains of A. nidulans to synthesize the fungal secondary metabolites asperbenzaldehyde, citreoviridin, and mutilin when grown on these digestion products. This hybrid approach considerably expands the range of products to which polyethylenes can be upcycled. [ABSTRACT FROM AUTHOR]

• The influences of electronic metal-support interactions (EMSI) on the catalytic hydrogenation of ethylene over Pd n /CeO2 (n = 4, 7, 10) have been studied. • The charge redistribution on the Pd cluster creates 2 typical sites: IF sites located at the interface between metal and support and T sites located at the topmost of the cluster. • IF sites show extremely higher activity for H 2 dissociation and T sites show better activity for ethylene hydrogenation. • At high H coverage, both the kinetics and thermodynamics of the hydrogenation reaction would be significantly promoted. • The two types of sites should collaborate synergically to promote the hydrogenation process. The catalytic activity of supported catalyst is closely related to the electronic metal-support interactions (EMSI). In this paper, first principles density functional theory study was conducted to understand the EMSI between Pd clusters (Pd 4 , Pd 7 , Pd 10) and CeO 2 substrate. When Pd was loaded on CeO 2 surface, the electrons of Pd would transfer to the CeO 2 substrate via Pd-O bonding interactions. Moreover, the charge redistribution on the Pd cluster leads to significant polarization of electron density. Consequently, the Pd atoms located at the metal-support interface (IF site) are positively charged, while the Pd atoms at the topmost (T site) are negatively charged. The H 2 dissociation and ethylene hydrogenation at these sites were calculated with both low and high hydrogen coverage. It was found that the two types of sites should collaborate synergically to promote the hydrogenation of ethylene. In particular, the IF sites exhibit relatively high activity for H 2 dissociation, while the T sites show superior catalytic efficiency for ethylene hydrogenation. Therefore, the EMSI induced charge polarization can tune the electronic structure and charge state of supported metal catalysts, which further determines the performance of different region on the catalyst. [Display omitted] [ABSTRACT FROM AUTHOR]

Cover Picture: Conversion of Polyethylenes into Fungal Secondary Metabolites (Angew. Polyethylenes are first cleaved into carboxylic diacids using catalytic oxidation. Polyethylenes are first cleaved into carboxylic diacids using catalytic oxidation. [Extracted from the article]

Keywords: Biosynthesis; Catalysis; Polyethylenes; Synthetic Biology; Upcycling EN Biosynthesis Catalysis Polyethylenes Synthetic Biology Upcycling 1 1 1 01/19/23 20230123 NES 230123 B A novel, two-step chemical-biological approach b converts post-consumer polyethylenes into structurally diverse and pharmacologically active fungal natural products, as reported by Travis J. Williams, Clay C. C. Wang et al. in their Research Article (e202214609). Polyethylenes are first cleaved into carboxylic diacids using catalytic oxidation. Polyethylenes are first cleaved into carboxylic diacids using catalytic oxidation. [Extracted from the article]