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The poor electrochemical stability window and low ionic conductivity in solid‐state electrolytes hinder the development of safe, high‐voltage, and energy‐dense lithium metal batteries. Herein, taking advantage of the unique electronic effect of nitrile groups, we designed a novel azanide‐based single‐ion covalent organic framework (CN−iCOF) structure that possesses effective Li+ transport and high‐voltage stability in lithium metal batteries. Density functional theory (DFT) calculations and molecular dynamics (MD) revealed that electron‐withdrawing nitrile groups not only resulted in an ultralow HOMO energy orbital but also enhanced Li+ dissociation through charge delocalization, leading to a high tLi+ of 0.93 and remarkable oxidative stability up to 5.6 V (vs. Li+/Li) simultaneously. Moreover, cyanation leveraging Strecker reaction transformed reversible imine‐linkage to a stable sp3‐carbon‐containing azanide anion, which facilitated contorted alignment of transport "ladders" along the one‐dimensional anionic channels and the ionic conductivity could reach 1.33×10−5 S cm−1 at ambient temperature without any additives. As a result, CN−iCOF allowed operation of solid‐state lithium metal batteries with high‐voltage cathodes such as LiNi0.8Mn0.1Co0.1O2 (NCM811), demonstrating stable lithium deposition up to 1,100 h and reversible battery cycling at ambient temperature up to 4.5 V, shedding light on the importance of discovering new functionality for forthcoming high‐performance batteries. [ABSTRACT FROM AUTHOR]

Alternating copolymers are crucial for diverse applications. While dispersity (Ð, also known as molecular weight distribution, MWD) influences the properties of polymers, achieving low dispersities in alternating copolymers poses a notable challenge via free radical polymerizations (FRPs). In this work, we demonstrated an unexpected discovery that dispersities are affected by the participation of charge transfer complexes (CTCs) formed between monomer pairs during free radical alternating copolymerization, which have inspired the successful synthesis of various alternating copolymers with low dispersities (>30 examples, Ð=1.13–1.39) under visible‐light irradiation. The synthetic method is compatible with binary, ternary and quaternary alternating copolymerizations and is expandable for both fluorinated and non‐fluorinated monomer pairs. DFT calculations combined with model experiments indicated that CTC‐absent reaction exhibits higher propagation rates and affords fewer radical terminations, which could contribute to low dispersities. Based on the integration of Monte Carlo simulation and Bayesian optimization, we established the relationship map between FRP parameter space and dispersity, further suggested the correlation between low dispersities and higher propagation rates. Our research sheds light on dispersity control via FRPs and creates a novel platform to investigate polymer dispersity through machine learning. [ABSTRACT FROM AUTHOR]

Controlled radical copolymerizations present attractive avenues to obtain polymers with complicated compositions and sequences. In this work, we report the development of a visible‐light‐driven organocatalyzed controlled copolymerization of fluoroalkenes and acyclic N‐vinylamides for the first time. The approach enables the on‐demand synthesis of a broad scope of amide‐functionalized main‐chain fluoropolymers via novel fluorinated thiocarbamates, facilitating regulations over chemical compositions and alternating fractions by rationally selecting comonomer pairs and ratios. This method allows temporally controlled chain‐growth by external light, and maintains high chain‐end fidelity that promotes facile preparation of block sequences. Notably, the obtained F/N hybrid polymers, upon hydrolysis, afford free amino‐substituted fluoropolymers versatile for post modifications toward various functionalities (e.g. amide, sulfonamide, carbamide, thiocarbamide). We further demonstrate the in situ formation of polymer networks with desirable properties as protective layers on lithium metal anodes, presenting a promising avenue for advancing lithium metal batteries. [ABSTRACT FROM AUTHOR]

Controlling the structure and chemistry of solid electrolyte interphase (SEI) underpins the stability of electrolyte‐electrode interface, and is crucial for advancing rechargeable lithium metal batteries (LMBs). Here, we utilized photo‐controlled copolymerization to achieve the on‐demand synthesis of fluorosulfonyl fluoropolymers as unprecedented artificial SEI layers on Li metal anodes. This work not only enables instant formation of a hybrid polymer‐inorganic interphase that consists of a polymer‐enriched top layer and a LiF‐fortified bottom layer, originating from a single polymeric component, but also imparts various desirable physical properties (e.g. good mechanical strength and flexibility, high ion conductivity, low overpotential) to SEI via a single‐to‐divergent strategy. Model reactions and structural characterizations supported the formation of a divergent fluorinated interphase, which furnished prolonged stabilization of Li deposition, high coulombic efficiency and improved cycling behavior in electrochemical experiments. This work highlights the great potential of exploring reactive polymers as versatile coatings to stabilize Li metal anodes, providing a promising avenue to solve electrode‐electrolyte interfacial problems for LMBs. [ABSTRACT FROM AUTHOR]

Ultrahigh‐molecular‐weight (UHMW) polymers with tailored structures are highly desirable for the outstanding properties. In this work, we developed a novel photoorganocatalyzed controlled radical alternating copolymerizations of fluoroalkyl maleimide and diverse vinyl comonomers, enabling efficient preparation of fluorinated copolymers of predetermined UHMWs and well‐defined structures at high conversions. Versatility of this method was demonstrated by expanding to controlled terpolymerization, which allows facial access toward fluorinated terpolymers of UHMWs and functional pendants. The obtained copolymers exhibited attractive physical properties and furnished thermoplastic, anticorrosive and (super)hydrophobic attributes as coatings on different substrates. Molecular simulations provided insights into the coating morphology, which unveiled a fluorous protective layer on the top surface with polar groups attached to the bottom substrate, resulting in good adhesion and hydrophobicity, simultaneously. This synthetic method and customized copolymers shed light on the design of high‐performance coatings by macromolecular engineering. [ABSTRACT FROM AUTHOR]

Fluorinated polymers are important materials that are widely used in many areas. Herein, we report the development of a metal-free photocontrolled radical polymerization of semifluorinated (meth)acrylates with a new visible-light-absorbing organocatalyst. This method enabled the production of a variety of semifluorinated polymers with narrow molar-weight distributions from semifluorinated trithiocarbonates or perfluoroalkyl iodides. The high performance of 'ON/OFF' control and chain-extension experiments further demonstrate the utility and reliability of this method. Furthermore, to streamline the preparation of semifluorinated polymers, a scalable continuous-flow approach has been developed. Given the broad interest in fluorinated materials and photopolymerization, we expect that this method will facilitate the development of advanced materials with unique properties. [ABSTRACT FROM AUTHOR]

A general, rapid, and efficient method for the copper-catalyzed Finkelstein reaction of (hetero)aromatics has been developed using continuous flow to generate a variety of aryl iodides. The described method can tolerate a broad spectrum of functional groups, including N-H and O-H groups. Additionally, in lieu of isolation, the aryl iodide solutions were used in two distinct multistep continuous-flow processes (amidation and Mg-I exchange/nucleophilic addition) to demonstrate the flexibility of this method. [ABSTRACT FROM AUTHOR]