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Aprotic Li‐CO2 batteries suffer from sluggish solid‐solid co‐oxidation kinetics of C and Li2CO3, requiring extremely high charging potentials and leading to serious side reactions and poor energy efficiency. Herein, we introduce a novel approach to address these challenges by modulating the reaction pathway with tailored Pt d‐electrons and develop an aprotic Li‐CO2 battery with CO and Li2CO3 as the main discharge products. Note that the gas‐solid co‐oxidation reaction between CO and Li2CO3 is both kinetically and thermodynamically more favorable. Consequently, the Li‐CO2 batteries with CoPt alloy‐supported on nitrogen‐doped carbon nanofiber (CoPt@NCNF) cathode exhibit a charging potential of 2.89 V at 50 μA cm−2, which is the lowest charging potential to date. Moreover, the CoPt@NCNF cathode also shows exceptional cycling stability (218 cycles at 50 μA cm−2) and high energy efficiency up to 74.6 %. Comprehensive experiments and theoretical calculations reveal that the lowered d‐band center of CoPt alloy effectively promotes CO desorption and inhibits further CO reduction to C. This work provides promising insights into developing efficient and CO‐selective Li‐CO2 batteries. [ABSTRACT FROM AUTHOR]

Converting CO2 into valuable chemicals has become a widely used research method for CO2 conversion. In this work, the catalytic performance of pyramidal-4Ni catalysts supported on rare earth metal-doped CeO2 toward CO2 reduction reaction (CO2RR) was investigated by using density-functional theory calculations. For rare earth metal-doped CeO2, 2Ce is substituted by 2 trivalent cations and at the same time one oxygen vacancy is created to make charge compensation. We investigated the oxygen vacancy nearest (VO,N) and next-nearest (VO,NN) to 4Ni, and found releasing CO and CO2 dissociation are the rate-determining steps, respectively, via the path of VO,N and VO,NN. Among the studied dopants (Ga, Sb, Lu, Gd, Pr, La, Bi), Gd is identified as the best dopant for catalyzing the reduction of CO2 at 823 K, with the turn-over frequency (TOF) of 104 times as large as that over 4Ni supported on pure CeO2. This exploration pro-vides theoretical support and guidance for the research and application of rare earth metaldoped CeO2-loaded Ni catalysts in the field of CO2 reduction. [ABSTRACT FROM AUTHOR]

The instability of the solid electrolyte interface (SEI) is a critical challenge for the zinc metal anodes, leading to an erratic electrode/electrolyte interface and hydrogen evolution reaction (HER), ultimately resulting in anode failure. This study uncovers that the fluorine species dissolution is the root cause of SEI instability. To effectively suppress the F− dissolution, an introduction of a low‐polarity molecule, 1,4‐thioxane (TX), is proposed, which reinforces the stability of the fluorine‐rich SEI. Moreover, the TX molecule has a strong affinity for coordinating with Zn2+ and adsorbing at the electrode/electrolyte interface, thereby diminishing the activity of local water and consequently impeding SEI dissolution. The robust fluorine‐rich SEI layer promotes the high durability of the zinc anode in repeated plating/stripping cycles, while concurrently suppressing HER and enhancing Coulombic efficiency. Notably, the symmetric cell with TX demonstrates exceptional electrochemical performance, sustaining over 500 hours at 20 mA cm−2 with 10 mAh cm−2. Furthermore, the Zn||KVOH full cell exhibits excellent capacity retention, averaging 6.8 mAh cm−2 with 98 % retention after 400 cycles, even at high loading with a lean electrolyte. This work offers a novel perspective on SEI dissolution as a key factor in anode failure, providing valuable insights for the electrolyte design in energy storage devices. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER) is an essential process for hydrogen production through water splitting. Atom-doped carbon nanotubes (CNTs) exhibit significant potential in promoting the electrocatalytic HER. By performing density functional theory (DFT) calculations, we have screened HER performance over a series of single atom transition metals (TM = Mo, Rh, Fe, Cr, Co, Zn, Mn, Cu, Ni, Pd) anchored on CNTs (n, n) (n = 5, 10) and graphene (seen as a CNT with the smallest curvature), and found the volcano curves between the adsorption free energy of H* (ΔGH*) and the current density for the HER, yielding the RhN4 catalyst at the peak of the volcano and even with a current density higher than that of Pt when the curvature is smaller than (10, 10). Then, more detailed DFT calculations were conducted to investigate the effect of curvature of CNTs on tuning the HER activity of RhN4@CNT (n, n) (n = 5–10) catalysts, where ΔGH* decreased with the decrease of the curvature, suggesting CNT-supported single atom catalysts having curvature-switched HER activity. The improved HER activity at a higher curvature arose from the more upshifted d-band center. Creating one single vacancy (5-1DB defect) could further enhance the HER activity of RhN4@CNTs. Our work provides a novel approach to designing HER catalysts with tunable activity and stability. [ABSTRACT FROM AUTHOR]

Controlling lithium (Li) electrocrystallization with preferred orientation is a promising strategy to realize highly reversible Li metal batteries (LMBs) but lack of facile regulation methods. Herein, we report a high‐flux solid electrolyte interphase (SEI) strategy to direct (110) preferred Li deposition even on (200)‐orientated Li substrate. Bravais rule and Curie‐Wulff principle are expanded in Li electrocrystallization process to decouple the relationship between SEI engineering and preferred crystal orientation. Multi‐spectroscopic techniques combined with dynamics analysis reveal that the high‐flux CF3Si(CH3)3 (F3) induced SEI (F3‐SEI) with high LiF and −Si(CH3)3 contents can ingeniously accelerate Li+ transport dynamics and ensure the sufficient Li+ concentration below SEI to direct Li (110) orientation. The induced Li (110) can in turn further promote the surface migration of Li atoms to avoid tip aggregation, resulting in a planar, dendrite‐free morphology of Li. As a result, our F3‐SEI enables ultra‐long stability of Li||Li symmetrical cells for more than 336 days. Furthermore, F3‐SEI modified Li can significantly enhance the cycle life of Li||LiFePO4 and Li||NCM811 coin and pouch full cells in practical conditions. Our crystallographic strategy for Li dendrite suppression paves a path to achieve reliable LMBs and may provide guidance for the preferred orientation of other metal crystals. [ABSTRACT FROM AUTHOR]

Ag exhibits high selectivity of electrochemical CO 2 reduction (CO 2 R) toward C 1 products, while the hydrogenation involving the concerted proton-electron transfer (CPET) or sequential electron-proton transfer (SEPT) mechanism is still in debate. Toward a better understanding of the Ag-catalyzed electrochemical CO 2 R, we employed a microkinetic model based on the Marcus electron transfer theory to thoroughly investigate the selectivity of C 1 products of electrochemical CO 2 R over the Ag(111) surface. We found that at an acidic condition of pH = 1.94, formate is the main product when U < -0.94 V via the CPET mechanism, whereas CO becomes the primary product when U > -0.94 V via the SEPT mechanism. Conversely, at an alkaline condition of pH = 13.95, formate is the main product following the SEPT mechanism. Our findings provide novel insights into the influence of external factors (applied potential and pH) on the product selectivity and hydrogenation mechanism of electrochemical CO 2 R.

The chemical engineering of natural extracts has emerged as an effective strategy for the production of diverse libraries of chemicals, making it integral to drug discovery. A chemical engineering strategy based on the epoxidation and ring-opening reactions was used to prepare diversity-enhanced extracts of Chaetomium madrasense 375. Eleven unnatural cytochalasan derivatives ( 1-11 ) with unique functional groups, such as amine and isoxazole, were isolated and characterized from these chemically engineered extracts of C. madrasense 375. The identification of these new structures was accomplished through comprehensive spectroscopic analysis, supplemented by synthetic considerations. Notably, compounds 5 and 13 - 16 displayed potent phytotoxic effects on Arabidopsis thaliana , while compounds 1 , 2 , 5 , 10 , and 12 demonstrated inhibitory activities on LPS-induced NO production in RAW264.7 cells. Among them, compound 1 was found to be able to inhibit the upregulated expression of the inducible nitric oxide synthase (iNOS) protein induced by LPS, while also decreasing the production of pro-inflammatory cytokines (IL-6) and influencing the phosphorylation of p38, ERK1/2, and JNK at 100 μM. Our findings demonstrate that the chemical engineering of natural product extracts can be an efficient technique for the generation of novel bioactive molecules., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Guo, Shen, Wang, Shi, Ren, Li, Yin, Zhang, Yang, Wang, Ding and Chen.)

We herein report a phosphine-catalyzed (3 + 2) annulation of cyclopropenones with a wide variety of electrophilic π systems, including aldehydes, ketoesters, imines, isocyanates, and carbodiimides, offering products of butenolides, butyrolactams, maleimides, and iminomaleimides, respectively, in high yields with broad substrate scope. An α-ketenyl phosphorous ylide is validated as the key intermediate, which undergoes preferential catalytic cyclization with aldehydes rather than stoichiometric Wittig olefinations. This phosphine-catalyzed activation of cyclopropenones thus supplies a versatile C 3 synthon for formal cycloadditon reactions., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)