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The chemical binding between metal compounds and polysulfides provides a good solution to inhibit shuttle effect in Li‐S batteries. However, the Sabatier principle predicts that overly strong adsorption will commonly hinder the conversion of polysulfides, so building the synergetic effect mechanism between "strong adsorption" and "fast conversion" for polysulfides is a significant strategy. To realize this goal, in this study, the defect‐enriched Co9S8 hollow prisms (DHCPs) as both S host and catalyst material for Li‐S batteries are designed. Based on in situ UV–vis spectroscopy results, it is found that DHCPs can profitably promote the generation of S3·−${\rm{S}}_3^{\cdot{\bm{ - }}}$ radicals during the discharge process. In the case of the relatively high conversion barrier of "liquid–liquid" reaction, the generated S3·−${\rm{S}}_3^{\cdot{\bm{ - }}}$ radicals are responsible for the fast conversion reaction via a unique reaction pathway. When the sulfur loading is 4.63 mg cm−2, the cell with DHCP/S cathode delivers a high areal capacity of 4.75 mAh cm−2 at 0.1 C and keeps a high capacity of 2.99 mAh cm−2 after 100 cycles at 0.5 C. This study provides a positive attempt to achieve "strong adsorption" and "fast conversion" of polysulfides simultaneously, which will convincingly boost the development and practical process of Li‐S batteries. [ABSTRACT FROM AUTHOR]

In this study, poly(p‐phenylenediamine) (PPDA) was synthesized by an enzymatic polymerization method using p‐phenylenediamine as the monomer in the water phase. The PPDA structure was characterized by infrared (IR), gel permeation chromatography, and elemental analysis. The antioxidation behavior of the as‐synthesized PPDA in biodegradable castor oil was investigated using a rotary oxygen bomb test and pressurized differential scanning calorimetry. A theoretical calculation was conducted to investigate its antioxidation mechanism. PPDA was found to exhibit excellent oxidation resistance in castor oil at 150 °C, which effectively prolonged the oxidation induction time of the oil. The results obtained herein suggest that as with phenolic antioxidants, PPDA with a hindered structure effectively improves the antioxidation performance of the oil by enhancing the stability of nitrogen free radicals. [ABSTRACT FROM AUTHOR]

We report a general method for selective cross‐coupling of α,β‐unsaturated carboxylic acids with aryl tosylates enabled by versatile Pd(II) complexes. This method features the general cross‐coupling of ubiquitous α,β‐unsaturated carboxylic acids by decarboxylation. The transformation is characterized by its operational simplicity, the use of inexpensive, air‐stable Pd(II) catalysts, scalability and wide substrate scope. The reaction proceeds with high trans selectivity to furnish valuable (E)‐1,2‐diarylethenes. [ABSTRACT FROM AUTHOR]