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Alkynes generally serve as C2 synthons in transition‐metal‐catalyzed C−H annulations, herein, exploiting electron‐deficient alkynes as unconventional C1 synthons, the chemo‐ and regiospecific synthesis of functionalized 1H‐imidazo[1,5‐a]indol‐3(2H)‐ones via a redox‐neutral rhodium(III)‐catalyzed [4+1] annulation of N‐carbamoyl indoles has been achieved. This process is characterized by high chemo‐ and regioselectivity, broad substrate scope, good tolerance of functional groups, moderate to high yields and mild redox‐neutral conditions, thus affording a robust approach to access valuable 1H‐imidazo[1,5‐a]indol‐3(2H)‐ones. [ABSTRACT FROM AUTHOR]

The development of metallic lithium anode is restrained by lithium dendrite growth during cycling. The solid polymer electrolyte with high mechanical strength and lithium ion conductivity could be applied to inhibit lithium dendrite growth. To prepare the high‐performance solid polymer electrolyte, the environment‐friendly and cheap bacterial cellulose (BC) is used as filler incorporating with PEO‐based electrolyte owing to good mechanical properties and Li salts compatibility. PEO/LiTFSI/BC composite solid polymer electrolytes (CSPE) are prepared easily by aqueous mixing in water. The lithium ion transference number of PEO/LiTFSI/BC CSPE is 0.57, which is higher than PEO/LiTFSI solid polymer electrolyte (SPE) (0.409). The PEO/LiTFSI/BC CSPE exhibits larger tensile strength (4.43 MPa) than PEO/LiTFSI SPE (1.34 MPa). The electrochemical window of composite electrolyte is widened 1.43 V by adding BC. Density functional theory calculations indicate that flex of PEO chains around Li atoms is suppressed, suggesting the enhanced lithium ion conductivity. Frontier molecular orbitals results suggest that an unfavorable intermolecular charge transfer lead to achieve higher potential for BC composite electrolyte. All solid‐state Li metal battery with PEO/LiTFSI/BC CSPE delivers longer cycle life for 600 cycles than PEO/LiTFSI SPE battery (50 cycles). Li symmetrical battery using PEO/LiTFSI/BC CSPE could be stable for 1160 h. [ABSTRACT FROM AUTHOR]

Developing effective electrocatalyst and deciphering its mechanism in modulating sulfur‐species‐conversion is still an important but challenging part for lithium sulfur (Li‐S) batteries. Here, a "spontaneous formed" strategy is presented to construct hierarchical CNT@ surface oxidized TiN nanoparticles (CNT@TiON) and the detailed interfaces mediation mechanism of Mott‐Schottky effect is disclosed on Li‐S chemistries. The results indicate the redistribution of local electron density in TiON is critical to enhancing the sulfur‐species utilization, lowering the energy barriers of intermediate step, and facilitating the conversion of PS. As a result, CNT@TiON‐S cathodes deliver significantly improved electrochemical performance, including low polarization, fleet reaction kinetics, and lasting cycle stability. This work embraces the local electronic state at heterojunction interface and paves a new way toward the design and understanding of efficient catalysts for Li‐S batteries. [ABSTRACT FROM AUTHOR]

Phase engineering of nanomaterials (PEN) is critically important for the preparation of nanomaterials with new phases, which are key for the investigation of phase‐dependent physicochemical properties and applications. This essay presents the state‐of‐the‐art development of PEN for the unique properties of nanomaterials with unconventional phases and their applications in energy storage and conversion and catalytic reactions. Finally, personal perspectives on the challenges and future opportunities of PEN in various applications are also provided. [ABSTRACT FROM AUTHOR]

It is of vital importance to develop novel, low-cost, and high-efficiency electrocatalysts for the oxygen reduction reaction (ORR), which have a considerable impact on electrochemical energy conversion and storage devices, such as fuel cells and metal−air batteries. In this work, we demonstrate highly active nitrogen-doped carbons with uniform hierarchical structures through sulfonated polystyrene (SPS), regulating the distribution of the PANI covering on carbon nanotubes (CNTs), prepared by using a reliable and controllable route. The as-prepared electrocatalyst shows outstanding activity towards the ORR in alkaline media, manifesting comparable or even better performance compared to commercial Pt/C. The optimized nitrogen-doped CNTs exhibit an onset potential ( Eonset) of 0.94 V (vs. reversible hydrogen electrode (RHE)) and half-wave potential ( E 1/2) of 0.83 V (vs. RHE) in 0.1 M KOH with superior stability, durability, and methanol tolerance, suggesting their promising applications in fuel cells and metal−air batteries. The significantly improved electrochemical properties demonstrate that the unique SPS layer anchoring on the surface of CNTs in the as-designed PANI@CNTs-SPS contributes to a uniform distribution of nitrogen sites throughout the catalyst. [ABSTRACT FROM AUTHOR]

Levodopa (L-dopa) is widely considered as one of the most effective drug constituents in the treatment of Parkinson's disease ( PD), but the blood-brain barrier ( BBB) permeability of L-dopa is <5%, which causes low efficacy. Neuroprotective effects of β-asarone on 6-hydroxydopamine (6- OHDA)-induced PD rats were demonstrated by our previous studies. Co-administration of β-asarone and L-dopa has not been explored until being investigated on PD rats in this study. PD rats were divided into four groups: untreated, L-dopa-treated, β-asarone-treated and co-administered-treated groups. All of the treatments were administered to the rats twice per day for 30 days. The L-dopa, dopamine ( DA), 3,4-dihydroxyphenylacetic acid ( DOPAC) and homovanillic acid ( HVA), S100 β and neuron-specific enolase ( NSE) levels were subsequently determined. The P-glycoprotein (P-gp), zonula occludens-1 ( ZO-1), claudin-5, occludin and actin expression was also assessed in cortex. Changes in BBB ultrastructure were observed using transmission electron microscopy. Our results showed that the co-administered treatment increased levels of L-dopa, DA, DOPAC and HVA in striatum, and S100 β in plasma, but down-regulated NSE, P-gp, ZO-1, occludin, actin and claudin-5 in cortex. Crevices were observed between capillary endothelial cells at intercellular tight junction of the striatum in co-administered-treated group, while the endothelial cells in untreated group were tightly jointing each other. In addition, the correlations of L-dopa or DA and P-gp or tight junction proteins respectively were significantly negative in co-administered- and β-asarone-treated groups. These findings suggest that co-administered treatment may enhance the L-dopa BBB permeability and attenuate brain injury, which may be beneficial to PD treatment. [ABSTRACT FROM AUTHOR]

Mott-Schottky Electrocatalyst: Spontaneously Formed Mott-Schottky Electrocatalyst for Lithium-Sulfur Batteries (Adv. Keywords: electrocatalysis; interfacial charge field; lithium sulfur-batteries; Mott-Schottky effect; spontaneous oxidation EN electrocatalysis interfacial charge field lithium sulfur-batteries Mott-Schottky effect spontaneous oxidation 1 1 1 11/23/20 20201119 NES 201119 Enhancing the catalytic activity of electrocatalyst in lithium sulfur electrochemistry by a facile method is important and challenging. In article number 1902092, Guoxin Gao, Shujiang Ding, and co-workers propose a spontaneous oxidation strategy to build Mott-Schottky electrocatalyst in lithium sulfur batteries. [Extracted from the article]