Designer Anions for Better Rechargeable Lithium Batteries and Beyond.

Non-aqueous electrolytes, generally consisting of metal salts and solvating media, are indispensable elements for building rechargeable batteries. As the major sources of ionic charges, the intrinsic characters of salt anions are of particular importance in determining the fundamental properties of bulk electrolyte, as well as the features of the resulting electrode-electrolyte interphases/interfaces. To cope with the increasing demand for better rechargeable batteries requested by emerging application domains, the structural design and modifications of salt anions are highly desired. Here, salt anions for lithium and other monovalent (e.g., sodium and potassium) and multivalent (e.g., magnesium, calcium, zinc, and aluminum) rechargeable batteries are outlined. Fundamental considerations on the design of salt anions are provided, particularly involving specific requirements imposed by different cell chemistries. Historical evolution and possible synthetic methodologies for metal salts with representative salt anions are reviewed. Recent advances in tailoring the anionic structures for rechargeable batteries are scrutinized, and due attention is paid to the paradigm shift from liquid to solid electrolytes, from intercalation to conversion/alloying-type electrodes, from lithium to other kinds of rechargeable batteries. The remaining challenges and key research directions in the development of robust salt anions are also discussed. This article is protected by copyright. All rights reserved.

Lithium Bis(fluorosulfonyl)imide for Stabilized Interphases on Conjugated Dicarboxylate Electrode.

Carbonyl-based negative electrodes have received considerable interest in the domain of rechargeable lithium batteries, owing to their superior feasibility in structural design, enhanced energy density, and good environmental sustainability. Among which, lithium terephthalate (LiTPA) has been intensively investigated as a negative electrode material in the past years, in light of its relatively stable discharge plateau at low potentials (ca. 1.0 V vs Li/Li+) and high specific capacity (ca. 290 mAh g-1). However, its cell performances are severely limited owing to the poor quality of the solid-electrolyte-interphase (SEI) layer generated therein. Here, we report the utilization of lithium bis(fluorosulfonyl)imide (LiFSI) as an electrolyte salt for forming a Li-ion permeable SEI layer on the LiTPA electrode and subsequently improving the cyclability and rate performance of the LiTPA-based cells. Our results show that, differing from the reference electrolyte containing the lithium hexafluorophosphate (LiPF6) salt, the electrochemical reductions of the FSI- anions occur prior to the lithiation processes of LiTPA electrode, which is capable of building an inorganic-rich SEI layer containing lithium fluoride (LiF) and lithium sulfate (Li2SO4). Consequently, the lithium metal (Li°)||LiTPA cell shows significantly improved cycling performance than the LiPF6-based reference cell. This work provides useful insight into the reductive processes of the FSI- anions on negative electrodes, which could spur the deployment of highly sustainable and high-energy rechargeable lithium batteries.

A reflection on polymer electrolytes for solid-state lithium metal batteries.

Before the debut of lithium-ion batteries (LIBs) in the commodity market, solid-state lithium metal batteries (SSLMBs) were considered promising high-energy electrochemical energy storage systems before being almost abandoned in the late 1980s because of safety concerns. However, after three decades of development, LIB technologies are now approaching their energy content and safety limits imposed by the rocking chair chemistry. These aspects are prompting the revival of research activities in SSLMB technologies at both academic and industrial levels. In this perspective article, we present a personal reflection on solid polymer electrolytes (SPEs), spanning from early development to their implementation in SSLMBs, highlighting key milestones. In particular, we discuss the SPEs' characteristics taking into account the concept of coupled and decoupled SPEs proposed by C. Austen Angell in the early 1990s. Possible remedies to improve the physicochemical and electrochemical properties of SPEs are also examined. With this article, we also aim to highlight the missing blocks in building ideal SSLMBs and stimulate research towards innovative electrolyte materials for future rechargeable high-energy batteries.

Anion Donicity of Liquid Electrolytes for Lithium Carbon Fluoride Batteries.

The increasing demand for high-energy powers have greatly incentivized the development of lithium carbon fluoride (Li||CFx ) cells. Five kinds of non-aqueous liquid electrolytes with various kinds of lithium salts (LiX, X=PF6 - , TFSI- , BF4 - , ClO4 - , and CF3 SO3 - ) were comparatively studied. Intriguingly, the LiBF4 -based electrolyte show relatively moderate ionic conductivities; yet, the corresponding Li||CFx cells deliver the highest discharge capacities among them. A combination of morphological and compositional analyses of the discharge CFx cathode suggest that the moderate donicity of BF4 - anion is accountable for favoring the breakdown of C-F bonds, and subsequently forming crystalline lithium fluoride as the main discharge products. This work brings not only fresh understanding on the role of salt anions for Li||CFx cells, but also inspire the electrolyte design for other conversion-type (sulfur and/or organosulfur) cathode materials desired for high-energy applications.

Effects of full-threaded headless cannulated compression screws and anatomical plates on the efficacy, safety, and prognosis of patients with triplane fractures of the distal tibia.

OBJECTIVE: To compare the clinical efficacy, safety, and prognosis of full-threaded headless cannulated compression screws (HCCSs) and anatomical plates (APs) in the treatment of triplane fractures of the distal tibia. METHODS: In this retrospective study, 74 patients with triplane fractures of the distal tibia treated in our hospital from April 2017 to March 2019 were selected as the research subjects. Among them, 38 patients receiving full-threaded HCCSs were assigned to the research group (RG), and the remaining 36 patients receiving APs were assigned to the control group (CG). The general indices, including operation, fracture healing, and ambulation times, efficacy, and complications were recorded and compared between the two groups. Visual analogue scale (VAS) was applied to assess pain, and a quality of life (QOL) survey was conducted at 6 months after surgery. RESULTS: Compared with the CG, the operation time, fracture healing time, and ambulation time of the RG were significantly shortened (P<0.05). The proportion of patients with excellent and good outcomes and Mazur Scores in the RG were higher than those in the CG (P<0.05). The frequency of complications in the RG was lower than that in the CG (P<0.05). The preoperative VAS score did not exhibit significant differences between the two groups (P<0.05), but the scores in the RG at T1 and T2 were significantly lower than those in the CG (P<0.001). The QOL score in the RG (76.17±8.57) was also significantly higher than in the CG (71.54±8.02) (P<0.05). CONCLUSION: Full-threaded HCCSs are more effective and safer than APs and can effectively improve the prognosis of patients with triplane fractures of the distal tibia.

Expression and anti-inflammatory role of activin receptor-interacting protein 2 in lipopolysaccharide-activated macrophages.

The bacterial endotoxin lipopolysaccharide (LPS), a key pathogenic stimulator, can induce the activation of macrophages. Activin receptor-interacting protein 2 (ARIP2), an intracellular signaling protein, has a wide histological distribution, however, whether ARIP2 is involved in regulation of activation of macrophages was not well characterized. Here, by immunocytochemical staining, we found that ARIP2 protein existed in monocyte-macrophage cell line RAW264.7 cells and peritoneal macrophages of mouse, and ARIP2 expression in RAW264.7 cells was up-regulated by LPS. Furthermore, the results revealed that ARIP2 overexpression in the LPS-activated RAW264.7 cells inhibited the productions of IL-1ß and TNFα, phagocytic activities and CD14 expression, whereas did not alter expressions of MyD88, TLR2 and TLR4. Additionally, in vivo ARIP2 overexpression also reduced the productions of IL-1ß and TNFα from the LPS-stimulated peritoneal macrophages of mouse. These data suggest that ARIP2 may play an anti-inflammatory role in macrophages via inhibiting CD14 expression.

The effects of activin A on the migration of human breast cancer cells and neutrophils and their migratory interaction.

Activin A belongs to the superfamily of transforming growth factor beta (TGFß) and is a critical regulatory cytokine in breast cancer and inflammation. However, the role of activin A in migration of breast cancer cells and immune cells was not well characterized. Here, a microfluidic device was used to examine the effect of activin A on the migration of human breast cancer cell line MDA-MB-231 cells and human blood neutrophils as well as their migratory interaction. We found that activin A promoted the basal migration but impaired epidermal growth factor (EGF)-induced migration of breast cancer cells. By contrast, activin A reduced neutrophil chemotaxis and transendothelial migration to N-Formyl-Met-Leu-Phe (fMLP). Finally, activin A promoted neutrophil chemotaxis to the supernatant from breast cancer cell culture. Collectively, our study revealed the different roles of activin A in regulating the migration of breast cancer cells and neutrophils and their migratory interaction. These findings suggested the potential of activin A as a therapeutic target for inflammation and breast cancers.

Selective Host-Guest Co-crystallization of Pyridine-Functionalized Tetraphenylethylenes with Phthalic Acids and Multicolor Emission of the Co-crystals.

Tetraphenylethylene (TPE) and its derivatives are the most typical and most widely studied organic compounds showing aggregation-induced emission (AIE). Due to their propeller-like structures, V-like clefts exist between the aryl rings, which make them promising host compounds. However, such a possibility is seldom explored. Herein, it is reported that TPE derivatives bearing two or four pyridine rings at the para positions of the phenyl rings (TPE-Pys) can selectively include triangular (Δ-like) m-phthalic acid from a mixture of o-, m-, and p-phthalic acids due to their shape complementary to form host-guest co-crystals, which showed redder emission than the TPE-Pys themselves. The emission of co-crystals 1-5 could be reversibly switched between yellow and red by alternating exposure to HCl and ammonia vapor. The host-guest co-crystals not only exhibited great potential for selectively recognizing and separating m-phthalic acid and as multicolor emission materials, but are also suitable for use as secret ink due to their reversible color change on varying the host-guest interactions.

Novel Li[(CF3SO2)(n-C4F9SO2)N]-Based Polymer Electrolytes for Solid-State Lithium Batteries with Superior Electrochemical Performance.

Solid polymer electrolytes (SPEs) would be promising candidates for application in high-energy rechargeable lithium (Li) batteries to replace the conventional organic liquid electrolytes, in terms of the enhanced safety and excellent design flexibility. Herein, we first report novel perfluorinated sulfonimide salt-based SPEs, composed of lithium (trifluoromethanesulfonyl)(n-nonafluorobutanesulfonyl)imide (Li[(CF3SO2)(n-C4F9SO2)N], LiTNFSI) and poly(ethylene oxide) (PEO), which exhibit relatively efficient ionic conductivity (e.g., 1.04 × 10-4 S cm-1 at 60 °C and 3.69 × 10-4 S cm-1 at 90 °C) and enough thermal stability (>350 °C), for rechargeable Li batteries. More importantly, the LiTNFSI-based SPEs could not only deliver the excellent interfacial compatibility with electrodes (e.g., Li-metal anode, LiFePO4 and sulfur composite cathodes), but also afford good cycling performances for the Li|LiFePO4 (>300 cycles at 1C) and Li-S cells (>500 cycles at 0.5C), in comparison with the conventional LiTFSI (Li[(CF3SO2)2N])-based SPEs. The interfacial impedance and morphology of the cycled Li-metal electrodes are also comparatively analyzed by electrochemical impedance spectra and scanning electron microscopy, respectively. These indicate that the LiTNFSI-based SPEs would be potential alternatives for application in high-energy solid-state Li batteries.

Single Lithium-Ion Conducting Polymer Electrolytes Based on a Super-Delocalized Polyanion.

A novel single lithium-ion (Li-ion) conducting polymer electrolyte is presented that is composed of the lithium salt of a polyanion, poly[(4-styrenesulfonyl)(trifluoromethyl(S-trifluoromethylsulfonylimino)sulfonyl)imide] (PSsTFSI(-)), and high-molecular-weight poly(ethylene oxide) (PEO). The neat LiPSsTFSI ionomer displays a low glass-transition temperature (44.3 °C; that is, strongly plasticizing effect). The complex of LiPSsTFSI/PEO exhibits a high Li-ion transference number (tLi (+) =0.91) and is thermally stable up to 300 °C. Meanwhile, it exhibits a Li-ion conductivity as high as 1.35×10(-4)  S cm(-1) at 90 °C, which is comparable to that for the classic ambipolar LiTFSI/PEO SPEs at the same temperature. These outstanding properties of the LiPSsTFSI/PEO blended polymer electrolyte would make it promising as solid polymer electrolytes for Li batteries.

Molecular modeling and biological effects of peptidomimetic inhibitors of TACE activity.

We investigated the molecular basis of specificity for the interaction between tumor necrosis factor-alpha converting enzyme (TACE) and peptidomimetic inhibitors. Four novel peptidomimetic TACE inhibitors (8a-d) were designed and synthesized by introducing a substituted sulfur group and a hydrophobic group to a novel matrix metalloprotease (MMP) inhibitor. Inhibition was determined by in vitro lipopolysaccharide (LPS) cytotoxicity tests in HL-60 cell lines and by measuring the expression of mTNF-alpha using FCM techniques and immunohistochemistry in vivo. We simulated the interaction of the inhibitors with the 3D structure of the TACE active site in the Brookhaven Protein Database (PDB). The four inhibitors (8a-d) inhibited activity by 9.1%, 54.5%, 27.3%, and 54.5%, respectively. 8b and 8d showed significant in vitro inhibition in cytotoxicity tests, which corresponded to the molecular docking results. 8d also showed inhibitory activity in vivo. We explored the interface between enzyme and substrate by combining bioinformatics with experimental observations to further the development of specific TACE inhibitors to reduce inflammatory responses.

Comparison of properties of tumor necrosis factor-alpha converting enzyme (TACE) and some matrix metalloproteases (MMPs) in catalytic domains.

The crystal structural data of TACE, MMP-1, MMP-2, MMP-3 and MMP-9 were obtained from PDB database, and then their catalytic domains' properties including conformation, molecular surface hydrophobicity and electrostatic potential were analyzed and compared by using Insight II molecular modeling software. It was found that the conformation and molecular surface hydrophobicity of catalytic domains of TACE and MMPs were not obviously different, but the molecular surface electrostatic potential of catalytic domain of TACE and MMPs had obvious differences. The findings are helpful in the Rational Drug Design of TACE selective inhibitor.

[The multiplex analysis of epigenetic markers and genetic markers by post-digestion mutagenically separated PCR].

OBJECTIVE: To establish a novel method for the multiplex analysis of the methylation and single nucleotide polymorphism (SNP). METHODS: The imprinted SNP rs220028 was chosen as a model. Genomic DNA, after being digested with methylation sensitive restriction enzyme, were typed by mutagenically separated PCR (MS-PCR). The polymorphism of restriction site was excluded by PCR-RFLP. RESULTS: By post-digestion MS-PCR, the methylated allele was detected selectively, the maternal origin of which was confirmed by pedigree analysis; A=0.5085, G=0.4915,PIC=0.3749. CONCLUSION: The multiplex analysis of methylation markers and SNP can be achieved by post-digestion MS-PCR. The imprinted SNP locus rs220028 is a potentially useful marker in screening Prader-Willi/Angelman syndrome.