The development of novel electrolytes for next-generation high voltage lithium ion battery is of primary importance. In this work, a fluorinated phosphazene derivative, ethoxy-(pentafluoro)-cyclotriphosphazene (PFN), is proposed as a novel electrolyte additive for improving the electrochemical performance and safety of lithium nickel manganese oxide (LiNi 0.5 Mn 1.5 O 4) cathode. With the addition of PFN, the electrolyte can be preferentially oxidized and decomposed, thus producing some linear polymers, multi-ring polymers, LiNO 3 , RONO 2 Li (RONO 2 : nitrate ester functional group, with R standing for any organic residue), Li 3 PO 4 , and ROPO 3 Li (ROPO 3 : monoester phosphate) simultaneously. These as-generated materials form a dense, uniform, and thin protective layer on the surface of the cathode material, which suppresses the decomposition of electrolyte and electrode corrosion, correspondingly protecting the LiNi 0.5 Mn 1.5 O 4 from structural destruction. Due to the coverage by the protective film and corrosion suppression, charge and discharge tests demonstrate that PFN is effective for improving the cycling stability of LiNi 0.5 Mn 1.5 O 4. The discharge capacity of a battery with 5 wt% PFN is 124.4 mAh g −1 and 99.8 mAh g −1 after 100 cycles at the current rates of 0.2 C and 1 C, respectively, which is much better than the performance without PFN. Meanwhile, because of the combined structure of the nonflammable cyclophosphazene and fluorine, the PFN creates a highly synergistic flame retardant effect, and a low content of PFN can almost completely extinguish burning electrolyte, leading to excellent safety performance for the lithium ion battery.

A direct regeneration of cathode materials from spent LiFePO4 batteries using a solid phase sintering method has been proposed in this article.

A series of cubic CoO nanocrystals with various morphologies and sizes were obtained via the decomposition of cobalt(II) oleate complex at 280-320 °C in noncoordinating solvent octadecene containing dodecanol/ oleic acid. The morphology of CoO nanocrystals could be conveniently tuned by manipulating the decomposition rate of cobalt oleate with the introduction of activating reagent dodecanol or inhibiting reagent oleic acid into the reaction system. More specifically, the morphology of CoO nanostructures can be tuned from the simple isolated tetrahedral shape to the complex 3D flowerlike shape by increasing the concentration of oleic acid, while with increasing concentration of dodecanol, the morphology of the CoO structures can be tuned from the 3D nanoflower to isolated spheres. The structure and morphology of the obtained CoO nanocrystals were characterized by X-ray diffraction (XRD) and by standard and high-resolution transmission electron microscopy (TEM and HRTEM), and the structural evolution and formation mechanism were also illustrated.

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CdTe-coated magnetic polystyrene nanospheres (MPN) were prepared via a stepwise electrostatic self-assembly approach, and the conjugation of epidermal growth factor (EGF) to the MPN/CdTe core-shell nanocomposites was prepared by using 1-ethyl-3(3-dimethylamino propyl)-carbodiimide (EDC) as a cross-linking reagent. The MPN/CdTe and their bioconjugates yielded not only emitted bright fluorescence, but also exhibited superparamagnetism. The human breast cancer MDA-MB-435S cells could be labelled and rapidly separated by the MPN/CdTe-EGF bioconjugates. These magnetofluorescent nanospheres, consisting of magnetic spheres and quantum dots (QDs), may be of special interest for many biomedical applications.

Increasing accumulation and retention of nanomedicines within tumor tissue is a significant challenge, particularly in the case of brain tumors where access to the tumor through the vasculature is restricted by the blood−brain barrier (BBB). This makes the application of nanomedicines in neuro-oncology often considered unfeasible, with efficacy limited to regions of significant disease progression and compromised BBB. However, little is understood about how the evolving tumor−brain physiology during disease progression affects the permeability and retention of designer nanomedicines. We report here the development of a modular nanomedicine platform that, when used in conjunction with a unique model of how tumorigenesis affects BBB integrity, allows investigation of how nanomaterial properties affect uptake and retention in brain tissue. By combining different in vivo longitudinal imaging techniques (including positron emission tomography and magnetic resonance imaging), we have evaluated the retention of nanomedicines with predefined physicochemical properties (size and surface functionality) and established a relationship between structure and tissue accumulation as a function of a new parameter that measures BBB leakiness; this offers significant advancements in our ability to relate tumor accumulation of nanomedicines to more physiologically relevant parameters. Our data show that accumulation of nanomedicines in brain tumor tissue is better correlated with the leakiness of the BBB than actual tumor volume. This was evaluated by establishing brain tumors using a spontaneous and endogenously derived glioblastoma model providing a unique opportunity to assess these parameters individually and compare the results across multiple mice. We also quantitatively demonstrate that smaller nanomedicines (20 nm) can indeed cross the BBB and accumulate in tumors at earlier stages of the disease than larger analogues, therefore opening the possibility of developing patient-specific nanoparticle treatment interventions in earlier stages of the disease. Importantly, these results provide a more predictive approach for designing efficacious personalized nanomedicines based on a particular patient's condition.

Currently adding a suitable additive in the electrolyte is one of the most effective strategies to improve the electrochemical performance for a lithium-ion battery, especially under high temperature. In this work, N,Ndimethylformamide (DMF) as an electrolyte additive was introduced to improve the battery performance of LiFePO 4 at 60 °C. The addition of DMF can effectively increase the specific capacity, cycling performance, and rate performance of batteries using LiFePO 4 as cathode material. X-ray diffraction results reveal that for the electrode cycled in the electrolyte without additive, Fe 2 O 3 , FePO 4 , and other impurity peaks appear under high temperature. scanning electron microscopy/transmission electron microscopy results indicate that some deposits are generated on the electrode surface without additive under high temperature due to the decomposition of electrolyte in the reaction between electrolyte and electrode materials. The Fourier transform infrared spectroscopy/NMR/X-ray photoelectron spectroscopy results demonstrate that DMF as a lewis base can capture lewis acidic PF 5 from the decomposition of LiPF 6 as well as block the chain reaction of LiFePO 4 with hydrogen fluoride, which alleviates the electrolyte decomposition and electrode dissolution at high temperature.

Monodisperse tetrapod-shaped CoO nanocrystals were prepared via the alcoholysis of cobalt (III) oleate in dodecanol at high temperature. The coordinating solvent dodecanol also acts as a reducing and morphology controller reagent. The size of the obtained CoO nanotetrapods can be well tuned by variation of the amount of dodecanol used. The chemical composition, structure and morphology of the obtained nanocrystals were characterized by using energy-dispersive x-ray analysis, powder x-ray diffraction, and transmission electron microscopy.