Covalent organic frameworks (COFs) with their porous structures that are accommodative of Li salts are considered to be potential candidates for solid-state fast Li conductors. However, Li salts simply infiltrated in the pores of solid-state COFs tend to be present in closely associate ion pairs, resulting in slow ionic diffusion dynamics. Here we incorporate cationic skeleton into the COF structure to split the Li salt ion pair through stronger dielectric screening. It is observed that the concentration of free Li ions in the resulting material is drastically increased, leading to a significantly improved Li conductivity in the absence of any solvent (up to 2.09 × 10 S cm at 70 °C).

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In this study, we demonstrate a facile method to fabricate novel Ni3S2 nano-triangular pyramid (NTP) arrays on Ni foam through a hydrothermal process and build unique Ni3S2@CoS core-shell NTP arrays by electro-deposition. The obtained Ni3S2@CoS material displays twice the specific capacitance of the pure Ni3S2 material in both a three-electrode system (4.89 F cm(-2) at 4 mA cm(-2)) and asymmetric supercapacitor device (0.69 F cm(-2) at 1.43 mA cm(-2)). In addition, the asymmetric supercapacitor demonstrates the outstanding energy density of 28.24 W h kg(-1) at a power density of 134.46 W kg(-1), with a stable cycle life (98.83% retained after 2000 cycles). The unique structure of the Ni3S2@CoS core-shell NTP arrays, which provides an ultra-thin CoS shell to enlarge efficient areas, introduces good conductivity, and short transportation lengths for both ions and electrons, contributes most to its excellent performance. Moreover, the bare Ni3S2 NTP arrays can be used as a new template to build other potential electrode materials.

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Highly toxic reactive oxygen species levels were enhanced via iron oxide core–shell mesoporous silica nanocarrier-mediated Fenton reactions for cancer therapy.

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Lithium-ion batteries dominate the battery field, particularly for electric and hybrid vehicles. Monoclinic Li 3 V 2 (PO 4) 3 has emerged as one of the most promising candidates for the cathode in lithium-ion batteries, offering better environmental safety and lower cost than competing materials. We have used in situ X-ray absorption spectroscopy to characterize the evolution of the vanadium in a Li 3 V 2 (PO 4) 3 cathode as it is cycled electrochemically. These data demonstrate the presence of significant kinetic effects such that the measured electrochemical behavior does not represent the bulk vanadium. When the cell is cycled between 3 and 4.5 V, there are two distinct vanadium species. When the potential is raised above 4.5 V, a third species is observed, consistent with formation of V 5+. XANES data for the cathode after 3−4.8 V cycling are consistent with a severely distorted vanadium site, suggesting that lithium−vanadium antisite mixing may be responsible for the electrochemical irreversibility that is seen above 4.5 V.

On-line remaining-useful-life (RUL) prognosis is still a problem for satellite Lithium-ion (Li-ion) batteries. Meanwhile, capacity, widely used as a health indicator of a battery (HI), is inconvenient or even impossible to measure. Aiming at practical and precise prediction of the RUL of satellite Li-ion batteries, a dynamic long short-term memory (DLSTM) neural-network-based indirect RUL prognosis is proposed in this paper. Firstly, an indirect HI based on the Spearman correlation analysis method is extracted from the battery discharge voltages, and the relationship between the indirect HI indices and battery capacity is established using a polynomial fitting method. Then, by integrating the Adam method, L2 regularization method, and incremental learning, a DLSTM method is proposed and applied for Li-ion battery RUL prognosis. Finally, verification of the results on NASA #5 battery data sets demonstrates that the proposed method has better dynamic performance and higher accuracy than the three other popular methods.