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The design of heterogeneous catalysts generally involves optimizing the reactivity descriptor of adsorption energy, which is inevitably governed by the structure of surface-active sites. A prerequisite for understanding the structure–properties relationship is the precise identification of real surface-active site structures, rather than relying on conceived structures derived from bulk alloy properties. However, it remains a formidable challenge due to the dynamic nature of nanoalloys during catalytic reactions and the lack of accurate and efficient interatomic potentials for simulations. Herein, a generalizable deep-learning potential for the Ag–Pd–F system is developed based on a dataset encompassing the bulk, surface, nanocluster, amorphous, and point defected configurations with diverse compositions to achieve a comprehensive description of interatomic interactions, facilitating precise prediction of adsorption energy, surface energy, formation energy, and diffusion energy barrier and is utilized to investigate the structural evolutions of AgPd nanoalloys during fluorination. The structural evolutions involve the inward diffusion of F, the outward diffusion of Ag in Ag@Pd nanoalloys, the formation of surface AgFx species in mixed and Janus AgPd nanoalloys, and the shape deformation from cuboctahedron to sphere in Ag and Pd@Ag nanoalloys. Moreover, the effects of atomic diffusion and dislocation formation and migration on the reconstructing pathway of nanoalloys are highlighted. It is demonstrated that the stress relaxation upon F adsorption serves as the intrinsic driving factor governing the surface reconstruction of AgPd nanoalloys. [ABSTRACT FROM AUTHOR]

Studies on the transformations of some functionalized cycloalkene derivatives through their ring olefin-bond aziridination/aziridine opening with fluoride are presented. The selected model compounds submitted to fluorinative functionalization were an amino ester and diesters with a cyclohexene skeleton as well as a cyclopentene-fused β-lactam. Functionalization proceeded across a substrate-directed diastereoselective olefin-bond aziridination, followed by fluoride-mediated aziridine opening or intramolecular lactonization giving some fluorinated amino ester or amino lactone derivatives. [ABSTRACT FROM AUTHOR]

We present here a high-efficiency, eco-friendly method for synthesizing alkyl fluorides (15 min, 50–89% yields) through halogen exchange, utilizing simple and readily available alkyl halides as starting materials. This catalyst-free method employs AgF as the fluorine source, operates under ball milling conditions, demonstrates broad functional group compatibility, and has found application in the synthesis of key intermediates for the marketed drug ledipasvir. [ABSTRACT FROM AUTHOR]

A simple mechanochemical protocol for solid-state aromatic nucleophilic fluorination using potassium fluoride (KF) and quaternary ammonium salts was developed. This solid-state fluorination is fast and a variety of N-heteroaryl halides can be efficiently fluorinated within 1 h. Notably, highly polar and high-boiling solvents, which are often toxic and difficult to remove during purification, are not required for this protocol. Moreover, all the synthetic operations can be carried out under ambient conditions without complicated setups involving inert gases. The practical advantages of this mechanochemical protocol suggest potentially widespread applications for the preparation of valuable fluorine-containing molecules in a more efficient, cost-effective, and environmentally friendly manner than existing solution-based protocols. [ABSTRACT FROM AUTHOR]

The development of a nucleophilic fluorination protocol using hydrofluoric acid as the fluoride source represents a long-sought goal in the field of organofluorine chemistry. We report herein the realization of such a reaction that employed alkyl-substituted sulfonium ylides as the substrates. The key to the success of the protocol was attributed to two factors: First, as a Brønsted base, the ylide was able to be protonated by HFaq, thus serving as a phase-transfer shuttle generated in situ to bring F− from aqueous phase to the organic phase promoting desolvation of fluoride ion. Second, after protonation, a sulfonium salt, a good leaving group, was generated and subsequent attacked by the fluoride to afford the alkyl fluoride. Mechanistic investigation indicates that the reaction occurs via an SN1 pathway. Because of the nature of the cationic intermediate in the reaction, two attractive rearrangement-fluorination approaches including 1,2-aryl migration fluorination and ring-expansion fluorination were disclosed. [ABSTRACT FROM AUTHOR]

Abstract\nHIGHLIGHTSFacile synthetic protocol has been designed for the topical corticosteroid Amcinonide. Topical corticosteroids are a group of mainly synthetic steroids utilized as anti-inflammatory and antipruritic agents. Amcinonide works by diminishing or blocking the actions of certain chemicals in the body that lead to inflammation, redness, and swelling. Current synthesis methods for Amcinonide are often complex and utilize hazardous materials. The innovative approach designed for synthesizing Amcinonide from tetraene acetate (3TR) involves three steps: oxidation, one-pot ketal-epoxide formation via bromohydrin, and fluorination. Present protocol offers several important benefits, including ease of operation, improved atom economy, reduced reaction time, and the incorporation of in-situ reaction.A novel protocol has been designed for the topical corticosteroid, Amcinonide.Present investigation offers many advantages over reported protocols such as Inexpensive, one-pot, step economy, and high percentage yield.Novel approach developed for synthesis of Amcinonide from tetraene acetate (3TR) which includes three steps oxidation, one-pot ketal-epoxide formation via bromohydrin, and fluorination.Present method:A novel protocol has been designed for the topical corticosteroid, Amcinonide.Present investigation offers many advantages over reported protocols such as Inexpensive, one-pot, step economy, and high percentage yield.Novel approach developed for synthesis of Amcinonide from tetraene acetate (3TR) which includes three steps oxidation, one-pot ketal-epoxide formation via bromohydrin, and fluorination.Present method: [ABSTRACT FROM AUTHOR]

Fluorinated ether‐based electrolytes are commonly employed in lithium metal batteries (LMBs) to attenuate the coordination ability of ether solvents with Li+ and induce inorganic‐rich interphase, whereas fluorination inevitably introduces exorbitant production expenses and environmental anxieties. Herein, a non‐fluorinated molecular design strategy has been conceptualized by incorporating methoxy as an electron‐donating group to generate a quasi‐conjugate effect for tuning the affinity of Li+‐solvent, thereby enabling the cyclic ether solvent 2‐methoxy‐1,3‐dioxolane with weak solvation ability and exceptional Li metal‐compatibility. Accordingly, the optimized electrolyte exhibits anion‐dominant solvation structure for inorganic‐rich interphase and fulfills an impressive Li plating/stripping Coulombic efficiency of 99.6 %. As‐fabricated Li||LiFePO4 full cells with limited Li (N/P=2.5) showcase a high capacity retention of 83 % after 150 cycles, indicating excellent cycling stability. Moreover, the full LMBs demonstrate exceptional tolerance towards a wide temperature range from −20 °C to 60 °C, displaying a remarkable capacity retention of 90 % after 110 cycles at −20 °C. Such a molecular design strategy offers a promising avenue for electrolyte engineering beyond fluorination in order to cultivate high‐performance LMBs. [ABSTRACT FROM AUTHOR]

Boron (B) is desirable for energetic applications due to high gravimetric and volumetric energy densities. However, their use is limited because the native oxide shells on their surfaces limit oxidation and heat release by acting as a diffusion barrier and dead weight that does not contribute to heat release during oxidation. This paper reports a facile and efficient method of blending B with perfluoro additives to obtain materials with augmented heat release. We use polytetrafluoroethylene (PTFE) as a fluorine source that reacts with the oxide layer exothermally and use thermochemical analysis to identify the optimum composition of PTFE to extract high energy from B as a result of synergistic oxidation and fluorination reactions. The reduction in ignition temperatures of B is also observed due to its blending with PTFE. In this work, we determined B/PTFE blends with lower ignition temperature and higher oxidative heat release. These effects are due to the gasification of native surface oxide by fluorine via exothermic reactions that facilitate the enhanced reactions in the exposed metal core by eliminating the kinetic/thermodynamic barrier in the diffusion of the oxidizer to the B particle core. The study demonstrates the optimized formulation of highly energetic blends of B/PTFE for energetic applications.

[Display omitted] • LaF 3 @SiO 2 yolk-shell heterostructure nanofibers are designed and facilely prepared. • LaF 3 @SiO 2 YSHNFs are firstly used as interlayer to obtain long-cycling Li-S battery. • "3 + 1" mode anchoring (quadruplex anchoring) is advanced to inhibit LiPSs shuttling. • "3 + 1" mode catalysis (quadruplex catalysis) is proposed to boost conversion of LiPSs. • Cavity of yolk-shell serves as a nanoreactor to promote conversion reaction of LiPSs. High-energy–density lithium–sulfur (Li–S) cells are identified as one of the most prospective next-generation energy storage appliances owing to their numerous advantages. Nonetheless, their widespread applications are restricted by the unwanted shuttling effect and tardy conversion reaction kinetics of lithium polysulfides (LiPSs). To address these puzzles, we present an innovative strategy for the one-pot synthesis of LaF 3 @SiO 2 yolk–shell heterostructure nanofibers (YSHNFs) through a straightforward uniaxial electrospinning process coupled with fluorination, avoiding the complexities of traditional methods. The specially designed LaF 3 @SiO 2 YSHNFs are utilized as an interlayer to modify a polypropylene (PP) film, creating a LaF 3 @SiO 2 /PP separator for long-cycle Li–S batteries. Peculiar "3 + 1" mode anchoring (quadruplex anchoring) and "3 + 1" mode catalysis (quadruplex catalysis) are present in the LaF 3 @SiO 2 YSHNFs, effectively inhibiting the LiPSs shuttling and enhancing their conversion reaction kinetics. Furthermore, the yolk–shell cavity acts as a nanoreactor, advancing the conversion of LiPSs on the LaF 3 @SiO 2 heterostructure. Owing to the strategic design of components and the distinctive structure of LaF 3 @SiO 2 YSHNFs, the combination of the quadruplex anchoring, the quadruplex catalysis, and the nanoreactor collectively contributes to a long-cyclic Li–S battery with high performances. The bare sulfur cathode using the LaF 3 @SiO 2 /PP separator exhibits an impressive incipient discharge capacity of 1514 mAh g−1 at 0.2 C and displays a decay rate of only 0.034 % per cycle at 2 C over 600 cycles with a distinguished stability. Density functional theory calculations offer insights into the mechanisms of quadruplex anchoring and catalytic conversion reactions involving the LaF 3 @SiO 2 heterostructure for LiPSs redox process. The strategies for interlayer design, concepts and techniques proposed in this study provide valuable guidance for developing yolk–shell structured materials for advanced long-cyclic Li–S batteries. [ABSTRACT FROM AUTHOR]

High nickel layered oxides provide high energy densities as cathodes for next‐generation batteries. However, critical issues such as capacity fading and voltage decay, which derive from labile surface reactivity and phase transition, especially under high‐rate high‐voltage conditions, prevent their commercialization. Here we propose a fluorination strategy to simultaneously introduce F atoms into oxygen layer and create a F aggregated interface. Substitution F for O stabilizes the layered ionic framework as the F ions can anchor the internal transition metal ions through strong TM−F bonding interaction, alleviating anisotropic lattice strain accumulation and release during the cycle, and promoting the Li+ dynamics diffusion. Meanwhile, the fluorinated interface induces the formation of a thin and stable CEI, ameliorating the detrimental issues like oxygen vacancy formation, the HF attacks and metal dissolution. The resultant fluorinated cathode delivers a high reversible capacity of 192.9 mAh g−1 at 10 C within the voltage range of 2.7–4.5 V. This fluorination strategy approach provides design concepts for the advanced cathodes that can meet the demands of high‐rate and high‐voltage applications in next‐generation batteries. [ABSTRACT FROM AUTHOR]

The fluorination of the peri‐substituted acenaphthyl scaffolds 5‐PhE‐Ace‐6‐PPh2 (1E, E=O, S, Se, Te) using XeF2 afforded the difluorinated products 5‐PhE‐Ace‐6‐PF2Ph2 (2E, E=O, S, Se, Te) and tetrafluorinated products 5‐PhEF2‐Ace‐6‐PF2Ph2 (3E, E=Se, Te) depending on the stoichiometry applied. Fluoride abstraction of 2E using Me3SiOTf gave rise to the chalcogenide supported fluorophosphonium ions [5‐PhE‐Ace‐6‐P(F)Ph2](OTf) (4O and 5E, E=S, Se, Te). The molecular structure of 4O features a tetrahedral P atom, whereas those of the heavier analogues (5E, E=S, Se) contain trigonal bipyramidal P atoms that arise from intramolecular LP(E)→σ*(P−F) interactions. [ABSTRACT FROM AUTHOR]

Using fluorinated mono‐alcohols, in particular hexafluoro‐isopropanol (HFIP), as a solvent can enhance chemical reaction rates in a spectacular manner. Previous work has shown evidence that this enhancement is related to the hydrogen‐bond structure of these liquids. Here, we investigate the hydrogen‐bond dynamics of HFIP and compare it to that of its non‐fluorinated analog, isopropanol. Ultrafast infrared spectroscopy experiments show that the dynamics of individual hydrogen‐bonds is about twice as slow in HFIP as in isopropanol. Surprisingly, from dielectric spectroscopy we find the opposite behavior for the dynamics of hydrogen‐bonded clusters: collective rearrangements are 3 times faster in HFIP than in isopropanol. This difference indicates that the hydrogen‐bonded clusters in HFIP are smaller than in isopropanol. The differences in cluster size can be traced to changes in the hydrogen‐bond donor and acceptor strengths upon fluorination. The smaller cluster size can boost reaction rates in HFIP by increasing the concentration of reactive, terminal OH‐groups of the clusters, whereas the fast collective dynamics can increase the rate of formation of hydrogen‐bonds with the reactants. The longer lifetime of the individual hydrogen‐bonds in HFIP can enhance the stability of the hydrogen‐bonded clusters, and so increase the probability of reactant‐solvent hydrogen‐bonding. [ABSTRACT FROM AUTHOR]

Rapid performance degradation in alkaline hydrogen evolution catalysts, attributed to low intrinsic activity and bubble‐shielding effects under high current densities, poses a significant obstacle to achieving industrial hydrogen production. In response, a novel phosphorus‐doped activated carbon‐loaded ruthenium cobalt fluoride‐based heterostructured catalyst (Ru‐CoF2@PAC) is developed. Acting as an "electron trader", this catalyst leverages the exceptional electron‐donating capability of fluoride anions bound to cobalt, effectively bringing the d‐band center of the Ru site close to the Fermi level. This optimizes the adsorption energy of the H intermediate (Ru‐H) in the Vomer step, subsequently facilitating rapid H conversion (H→H*). Moreover, the incorporated fluorine enhances catalyst hydrophilicity, significantly improving bubble diffusion kinetics at the catalyst surface and catalytic stability when operated under high current density. Remarkably, the Ru‐CoF2@PAC catalyst loaded with 1.1 wt.% Ru requires only 27 mV to achieve the 10 mA cm−2 current density needed to split water under alkaline conditions. Furthermore, the catalyst exhibits exceptional stability during at least 140 h of operation at 1200 mA cm−2 with negligible degradation. This study provides valuable insights for guiding the development of durable catalysts suitable for large‐scale industrial hydrogen production. [ABSTRACT FROM AUTHOR]

In recent years, there have been increasing efforts in the development of methodologies for incorporating fluorine-containing functional groups into organic scaffolds. Modern techniques have made fluorinated molecules more accessible than ever before, but many fluorination reactions still have limitations in their generality, predictability, sustainability, and cost-effectiveness. The methodological progress has a significant impact on drug discovery and materials science research. Photoredox catalysis has enabled the discovery of effective methods, providing access to druglike molecules. Photochemical methods paired with C–H functionalization provide powerful tools for property-driven research. Herein, we examine recent developments at the interface of photoredox catalysis and C–H functionalization. 1 Introduction 2 Fluorinations 3 Fluoroalkylations 4 Fluoroalkoxylations 5 Conclusion [ABSTRACT FROM AUTHOR]

A one pot room temperature synthesis of thionyl tetrafluoride (SOF4) from elemental fluorine (F2) and thionyl fluoride (SOF2) is reported. The selective decagram scale process (100 mmol) allows a quantitative preparation of SOF4 with high purity. The solid‐state structure has also been elucidated and compared with the reported gas phase one. The use of this reagent for the formation of the emerging pentafluorooxosulfate [cat][OSF5] anions led to the preparation of multiple ion‐pairs (cat=Ag, NEt3Me, PPN, PPh4) in different organic solvents. The SuFEx reservoir ability of this anion was studied and by tuning the solvent system, the reactivity of pure thionyl tetrafluoride was observed using Ag[OSF5] in THF and acetone. [ABSTRACT FROM AUTHOR]

Fluorination is an efficient strategy for improving organic solar cells (OSCs) efficiency, particularly by fluorinating the end group of emerging nonfullerene acceptors. Here, the fluorination effect was investigated by using small molecule donors with fluorine‐free (SBz) and fluorinated (SBz‐F) end groups, paired with the emerging nonfullerene acceptor Y6. Interestingly and unexpectedly, fluorination of the end group negatively affects OSCs efficiency, with fluorine‐free SBz:Y6 OSCs achieving a higher power conversion efficiency (PCE) of 11.05 % compared to the fluorine‐containing SBz‐F:Y6 blends (PCE=9.61 %). Analysis of space‐charge limited currents reveals lower and unbalanced hole/electron mobility in SBz‐F:Y6 compared to the SBz:Y6 blends. These findings are further supported by charge recombination dynamics and donor‐acceptor miscibility analyses. [ABSTRACT FROM AUTHOR]

Polymeric carbon nitride has attracted significant interest in heterogeneous photocatalysis due to its activity under visible‐light irradiation. Herein, we report on using carbon nitride‐coated NMR tubes for in situ studies of photocatalytic reaction mechanisms. In a first step, we exploited carbon nitride‐coated crimp vials as batch photoreactors for visible photocatalytic fluorinations of unactivated C(sp3)−H bonds, with moderate to excellent yields and reusability over multiple cycles. Eventually, carbon nitride‐coated NMR tubes were used as a photoreactor by coupling them with optical fiber irradiation directly inside the spectrometer. This enabled us to follow the reaction with in situ NMR spectroscopy identifying reactive intermediates otherwise elusive in conventional analyses. The method provides advantages for the study of photocatalytic mechanisms of complex reactions and substantially reduces the need of comparative tests for depicting reaction intermediates and conversion pathways. [ABSTRACT FROM AUTHOR]

Enamines are versatile building blocks for the synthesis of biologically active compounds. Nevertheless, only a limited number of strategies have been reported for preparing trisubstituted enamines in a regio‐ and stereoselective manner. Herein, we report a regiocontrolled 6‐endo and 5‐exo tethered carboamination of propargylic alcohols for the synthesis of trisubstituted enamines. High regioselectivity was achieved through fine‐tuning of the amine protecting group during the Pd‐catalyzed carboamination. The introduced trifluoromethylated tether enables further stereoselective functionalizations, such as hydrogenation and fluorination. [ABSTRACT FROM AUTHOR]

As the simplest oligomeric acceptors, dimerized acceptors (DAs) are easier to synthesize, and more importantly, they can retain good intermolecular interaction and photovoltaic properties of their parent small‐molecule acceptors (SMAs). Nevertheless, currently most efficient DAs are derived from banana‐shaped acceptors and they might suffer from inferior device stability with high diffusion coefficients. Herein, we design and synthesize two planar DAs (DMT‐FH and DMT‐HF) by bridging two linear‐shaped M‐series SMAs with a thiophene unit. The effects of fluorination position on the diffusion coefficients, power conversion efficiencies (PCEs) and stability of the DAs are systematically studied. Our results suggest that DMT‐HF with fluorination on the ending indanone groups shows enhanced intermolecular interactions, improved PCE and stability compared with the counterpart (DMT‐FH) with fluorination on the central indanone groups. Further optimization on the DMT‐HF‐based devices yields an outstanding PCE of 17.17 %, which is the highest among all linear‐shaped SMA‐based DAs. Notably, with the low diffusion coefficient (3.36×10−24 cm2 s−1) of DMT‐HF, the resulting device retains over 93 % of the initial PCE after 5000 h of continuous heating at 85 °C, suggesting its excellent thermal stability. The results highlight the importance of intermolecular interaction and fluorination for achieving efficient and stable polymer solar cells. [ABSTRACT FROM AUTHOR]

Efficient fluorination reactions are key in the late‐stage functionalization of complex molecules in medicinal chemistry, in upgrading chemical feedstocks, and in materials science. Radical C(sp3)−H fluorinations using Selectfluor® – one of the most popular fluorination agents – allow to directly engage unactivated precursors under mild photochemical or thermal catalytic conditions. However, H−TEDA(BF4)2 to date is overlooked and discarded as waste, despite comprising 95% of the molecular weight of Selectfluor®. We demonstrate that the addition of H−TEDA(BF4)2 at the start of fluorination reactions markedly promotes their rates and accesses higher overall yields of fluorinated products (~3.3 × higher on average across the cases studied) than unpromoted reactions. Several case studies showcase generality of the promotor, for photochemical, photocatalytic and thermal radical fluorination reactions. Detailed mechanistic investigations reveal the key importance of aggregation changes in Selectfluor® and H−TEDA(BF4)2 to fill gaps of understanding in how radical C(sp3)−H fluorination reactions work. This study exemplifies an overlooked reaction waste product being upcycled for a useful application. [ABSTRACT FROM AUTHOR]

Unlike the well-established fluoroalkylation, the direct incorporation of multiple fluorine atoms into small molecules via iterative fluorinations has been much less investigated. Herein, we report a hypervalent iodine catalytically selective multi-fluorination in which the fluorination degree is controlled by the delicate balance between the HF/amine ratios. The pros and cons of hypervalent iodine catalysis and the previously established electrochemical approach in the iterative multi-fluorinations are also provided. [ABSTRACT FROM AUTHOR]

Two new partially fluorinated dehydrobenzannulenes have been prepared by inter‐ and intramolecular oxidative homocoupling of diyne precursors. These systems contain fluorinated and nonfluorinated arene rings in a desymmetrized non‐alternant arrangement. Both macrocycles are roughly planar and organize into extended columns in the solid state. The assembly of these columns is mediated by the combination of dispersion interactions, slipped [π⋅⋅⋅π] stacking interactions of the perfluorinated rings with each other, and their association with the nonfluorinated rings in the molecules of the neighboring macrocycles. These results suggest that partial fluorination of dehydrobenzannulenes can serve as a versatile motif for their assembly into columnar superstructures. [ABSTRACT FROM AUTHOR]

A one-carbon difluorocyclopropanation/ring-expansion has been developed for the chiral synthon Cyrene, which is obtained via cellulose pyrolysis. The ring-enlargement was achieved by converting Cyrene (dihydrolevoglucosenone) into an enamine, reacting it with an in situ-generated difluorocarbene, and then heating it to ring-open the cyclopropane. Access to the product provides access to fluorinated analogues of this valuable chiral biomass derivative. [ABSTRACT FROM AUTHOR]

Borates have emerged as a significant resource for exploring birefringent materials in the UV frequency region. The π‐conjugated planar anions, such as the [BO3], [B2O5], and [B3O6] units, exhibiting strong polarizability anisotropy, are traditionally good structural models. Both fluorination and hydroxylation have been proven effective strategies to modulate the optical properties of the planar anions. Controlling the ratio between F and OH is the key to realizing a balanced performance between birefringence and bandgap. Based on a fluorination mechanism proposed recently, a novel hydroxyfluorooxoborate (C3N2H5)B3O3F2(OH)2 with an optimal F/OH ratio of 1/1 is synthesized. During the synthesis, another strategy known as "cation activation" is also employed, which further increases birefringence by introducing active cation units. With its superior performance, this compound exhibits a short UV cutoff edge at 214 nm and a substantial birefringence of 0.205 at 546 nm, surpassing the commercial birefringent crystal α‐BBO (0.122@532 nm). The synergy between F/OH‐ratio optimization and cation activation offers a practical methodology for developing UV birefringent materials. [ABSTRACT FROM AUTHOR]

The applications of fluorinated molecules in chemical biology are rapidly expanding driven by the unique properties of C−F bonds, leading to increased interest in methodologies for controlled introduction of this atom. In this study, we present the first method for late‐stage fluorination of tyrosine residues in proteins. Our results demonstrate that electrophilic fluorination using Selectfluor, a stable and non‐toxic reagent, offers a straightforward and cost‐effective method for labeling Cyanovirin‐N (CVN), a 101‐amino‐acid lectin with effective antiviral activity. Uni‐ and bidimensional 1H, 13C and 19F NMR analyses, along with mass spectrometry, revealed chemoselective fluorination of the three tyrosine residues in CVN without affecting its overall structure or mannose‐binding affinity. Additionally, we observed that other aromatic amino acids, such as tryptophan, phenylalanine, and histidine, are not fluorinated using this method. These findings advance our understanding of protein fluorination and its applications in studying structure, dynamics, and interactions, as well as other biological utilities. [ABSTRACT FROM AUTHOR]

We conducted a mechanistic and experimental study on zinc fluoride roasting for the recovery of NdFeB waste to address the difficulties faced during this pyrometallurgical recovery process, such as the high dependence on the quality of raw materials, the high energy consumption involved in roasting transformations, and the low added value of mixed rare earth products. Thermodynamic calculations showed the feasibility of fluorinating rare earths in NdFeB waste, and one-factor experiments were performed. The results showed that at a roasting temperature of 850 °C, a reaction time of 90 min, and 100% ZnF2 addition, the fluorination rate of rare earths could reach 95.69%. In addition, after analyzing the mesophase composition of a clinker under different roasting temperature conditions, it was found that, when the roasting temperature exceeded 850 °C, the fluorination rate of rare earths was reduced, which was consistent with the thermodynamic results. On this basis, response surface methodology (RSM) was used to carry out experiments to investigate in depth the effects of various factors and their interactions on the fluorination rate of rare earths, which provides a sufficient experimental basis for the recovery of NdFeB waste via fluorination roasting. The results of this study show that ZnF2 addition had the greatest influence on the rare earth fluorination reaction, followed by roasting temperature and roasting time. According to the optimization results of the model, the optimal roasting conditions were determined as follows: 119% ZnF2 addition at 828 °C, a roasting time of 91 min, and a rare earth element fluorination rate of 97.29%. The purity of the mixed fluorinated rare earths was as high as 98.92% after leaching the roasted clinker with 9 M hydrochloric acid at a leaching temperature of 80 °C, a liquid–solid ratio of 4 mL/g, and a leaching time of 2.5 h. This study will lay the foundation for promoting the application of pyrometallurgical technology in the recycling of NdFeB waste. [ABSTRACT FROM AUTHOR]

Birefringent materials play indispensable roles in modulating the polarization of light and are vital in laser science and technology. Units with π‐conjugation are regarded as potential functional modules for large optical anisotropy, such as planar [BO3]3−, [B3O6]3−, and [B3O3(OH)3]. However, the discovery of deep‐ultraviolet (DUV, λ ≤200 nm) birefringent materials still faces a serious challenge due to the limited band gap. Replacing hydroxyl anions [OH]− with fluorine anions F− in borates can cause the blueshift of the ultraviolet (UV) cutoff edge, however, the effect of this replacement on π‐conjugation units has not been systematically studied. Herein, based on template materials metaboric acid α‐B3O3(OH)3 with planar [B3O3(OH)3] units, we proposed an OH/F substitution strategy designing potential DUV birefringent materials. The designed B3O3(OH)2F, B3O3(OH)F2, and B3O3F3 exhibit large birefringence from 0.123 to 0.146 at 546 nm with DUV transparency based on first‐principles calculations, exceeding the performance of traditional α‐BaB2O4. Further electronic structure analysis reveals the band edge and bonding difference between [OH]− and F−, indicating the corresponding designed novel [BO2F], [B3O3(OH)2F], [B3O3(OH)F2] and [B3O3F3] units can act as potential DUV birefringent‐active functional modules with large structure anisotropy. This work offers the chemical difference of F− and [OH]− anions, and design‐strategy of new DUV birefringent materials. [ABSTRACT FROM AUTHOR]

The effect of fluorination of boron nitride fullerene B12N12 on its activity towards the favipiravir molecule (a drug against the COVID-19 virus) is studied by the density functional theory. Two types of fullerene fluorination are considered: external doping with the formation of the B12N12F2 structure and endohedral doping with the formation of the F–@B12N12 complex. It is shown that fluorinated clusters can attach favipiravir by the same mechanism as initial fullerene. It is found that the interaction between the drug and the endohedral complex is too weak, while external doping by fluorine increases the binding energy between the cluster and the drug. [ABSTRACT FROM AUTHOR]

The transformation of the Raman spectra from titanium foils after their fluorination in gas mixtures was experimentally studied. It was found that fluorination leads to a strong increase in the intensity of scattering bands from the initial components of the nanocoating of titanium foils. A new strong band at 905 ± 5 cm–1 and a wide continuum with a maximum at ~1700 cm–1 also appear and increase in intensity after fluorination. [ABSTRACT FROM AUTHOR]

Fluorination of two-dimensional (2D) antimonene hexagons synthesized through a colloidal bottom-up approach has been explored using microwave-induced plasma and reactive ion etching fluorination strategies through the generation of CF4. The stability of the fluorine bond has been corroborated through DFT calculations. This work paves the way for further halogen-derivative modifications of heavy 2D pnictogens. [ABSTRACT FROM AUTHOR]

The present study involves the synthesis of two energetic compounds that were synthesized by substitution reactions with 5-aminotetrazole. Notably, the representative energetic 2-fluoro-4,6-dinitro-N1,N3-di(1 h-tetrazol-5-yl)benzene-1,3-diamine (ZXC-91) exhibits good density (296 K, 1.807 g cm−3) and good detonation properties (D = 8490 ms−1, p = 31.0 GPa). Additionally, considering other advantages such as simple preparation, cheap raw material, good thermostability (Td = 262.2 °C), and insensitivity (IS = 15 J, FS= 144 N), compound ZXC-91 is an ideal insensitive high energy density materials (HEDMs) candidate. The present study involves the synthesis of two energetic compounds through substitution reactions with 5-aminotetrazole. Today, there is an emerging trend among scientists to incorporate tetrazole rings into energetic compounds. Similarly, the present study involves the synthesis of two energetic compounds that were also synthesized by substitution reactions with 5-aminotetrazole. Notably, the representative energetic 2-fluoro-4,6-dinitro-N1,N3-di(1 h-tetrazol-5-yl)benzene-1,3-diamine (ZXC-91) exhibits good density (296 K, 1.807 g cm−3) and excellent detonation properties (D = 8490 ms−1, p = 31.0 GPa). Additionally, considering other advantages such as simple preparation, cost-effective raw materials, excellent thermostability (Td = 262.2 °C), and insensitivity (IS = 15 J, FS= 144 N), compound ZXC-91 is an ideal insensitive high energy density materials (HEDMs) candidate. [ABSTRACT FROM AUTHOR]

In this work, three isomeric fluorinated bipyridyldicarboxamides were studied to evaluate the impact of the fluorine atom position on the structure, stability, Am(III)/Ln(III) separation, and photophysical properties of their complexes. The complexes of the fluorinated amides have a metal-to-ligand composition of 1:1, which is independent of the fluorine atom position or lanthanide metal. The bipyridyl fragments in the fluorinated complexes are flattened compared with those in unsubstituted ones. Ln-to-heteroatom distances are more affected by steric hindrance in the ligand and further by lanthanide ion radius contraction. This leads to significant effectivity of heavy lanthanide extraction compared with the light ones, particularly for 4F diamide. Fluorination leads to a slight variation in the excited triplet state of the complexes, and hence, the effectiveness of luminescence increases for Eu, Sm, and Tb complexes. Moreover, fluorination significantly affects the CIE chromaticity coordinates for the complexes. [ABSTRACT FROM AUTHOR]

Three non-fullerene acceptors (NFAs) with varying alkyl chain sizes and lengths but constant fluorine atoms were synthesized. BO-17F and HD-17F, with optimal fluorination, exhibit improved molecular packing and morphology, achieving efficiencies of 14.2% and 14.4%. This work highlights the importance of fine-tuning alkyl chains and fluorination levels in organic solar cells. [ABSTRACT FROM AUTHOR]