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Upgrading liquid electrolytes with all-solid-state electrolytes (ASEs) or quasi-solid-state electrolytes (QSEs) for solid-state batteries (SBs) have emerged not only to address the intrinsic disadvantages of traditional liquid lithium ion batteries, but also to offer more possibilities for the development of new battery chemistries. In this work, a novel rambutan-like yolk–shell-structured porous γ-AlOOH microsphere with a large specific surface area of 262.92 m2 g−1 was firstly obtained by a simple hydrothermal synthesis route, which was then utilized as a robust framework to assemble QSE via encapsulating abundant liquid electrolyte (LE). The obtained γ-AlOOH-QSE exhibits a high ionic conductivity of 4.0 × 10−3 S cm−1, a large lithium ion transference number (tLi+) of 0.76, as well as a wide electrochemical window of 4.72 V vs. Li/Li+. Moreover, the assembled cell of LiFePO4/γ-AlOOH-QSE/Li could maintain a high specific capacity of 144.4 mA h g−1 even after 120 cycles with almost negligible capacity decay, which could be mainly attributed to the excellent interfacial compatibility, prominent performance in suppressing lithium dendrite growth upon cycling (rigid characteristic), as well as the high ionic conductivity of γ-AlOOH-QSE (intrinsic advantage). This work could not only expand the applications of QSE with cost-effective aluminum-based oxides with facile fabrication strategy, but also will shed light on the construction of SEs with more integrated QSEs and ASEs in the field of advanced energy storage.

A fluorescent probe composed of BODIPY and 2,4-dinitrophenylhydrazine was designed for the detection of ClO−. The oxidizing reaction between probe and ClO− resulted in a distinct fluorescence enhancement together with a color variation from pink to orange. This probe showed excellent selectivity to ClO− among various ions including common reactive oxygen species and high sensitivity with a detection limit of 228 nM. A fast response (7 min) was observed, which made the probe a promising method in real-time detection. Furthermore, this probe was successfully applied to monitor ClO− in real-life water and living cells.

Hypochlorite serves as a powerful antimicrobial agent in human immune system, the detection of which is of great significance. Herein a novel fluorescent probe based on BODIPY dye and diaminomaleonitrile has been synthesized and characterized to sense hypochlorite. The fluorescence of the system is dramatically enhanced by ClO− due to the removal of C=N isomerization effect in physiological pH condition. The complete reaction only needs a few seconds, which enables the probe to facilitate real-time detection. This probe also has satisfactory selectivity for ClO− even in the presence of other interferential ions and shows high sensitivity with a detection limit of 19.8 nM. Furthermore, Probe 1 has been successfully applied to detect ClO− in real water samples.

High voltage LiNi0.5Mn1.5O4 cathodes are of prime importance for the development of next generation lithium-ion batteries (LIBs) with high energy density. LiNi0.5Mn1.5O4, however, always was attacked by the generated HF from the electrolyte decomposition during cycling, leading to instable surface structure and poor Li+ diffusion kinetic property. In this regard, YF3 with good thermal stability and excellent structural stability in the HF containing electrolyte, is chosen as coating layer to modify the surface of LiNi0.5Mn1.5O4. Ex-situ electrochemical impedance spectroscopy study and inductively coupled plasma analysis indicate that YF3 coating layer on the surface of LiNi0.5Mn1.5O4 could act as protect medium to effectively suppress side reactions between the LiNi0.5Mn1.5O4 surface and electrolyte, and thus enhance its structural stability and kinetics properties during repeated electrochemical reactions. As a result, LiNi0.5Mn1.5O4 after YF3 modification shows the improved capacity retention of 84% after 100 cycles at 0.1C, and 78 mAh g−1 could be obtained at 2C, much higher than those of the pristine LiNi0.5Mn1.5O4 cathode (78%, 24 mAh g−1). Furthermore, differential scanning calorimetry result confirms the enhanced thermal stability of LiNi0.5Mn1.5O4 after YF3 coating. These findings open up chance to prepare high performance LiNi0.5Mn1.5O4 cathode and promote development of LIBs with high energy density.

Organic-inorganic composite solid state electrolytes (SSEs), as one of the most attractive candidates for next generation SSEs, combines the both advantages of flexibility (from organic polymer) and structure rigidity (from robust inorganic constituent). In this work, a high performance three-dimensional (3D) crosslinked electrolyte with polymer poly(vinylidene fluoride) (PVDF) and polyethylene oxide (PEO) matrices is further modified by dispersing submicron fast ion conductor Li1.4Al0.4Ti1.6(PO4)3 (LATP). The optimal 3D composite SSE PVDF@10PEO-5LATP-5LiPF6 (PPLL) shows high ionic conductivities of 5.24 × 10−4 S cm−1 at 25 °C and above 10−3 S cm−1 at 50 °C. Galvanostatic cycling test demonstrates that PPLL contributes to electrochemical performances, with high capacity retention of 93.95% after 500 cycles for LiFePO4 cathode. Further investigations indicate its more benefits including excellent flexibility and superior safety. Intensive explorations imply that the interaction between dual-matrix degrades the respective crystallization through generating weak bonding, and the recombination with LATP further enhances ionic conductivity as well as structural stability of composite electrolyte via strengthening interface reaction, and reducing the organic crystallinity. This composite SSE with high conductivity and stability may be applied in next generation energy storage devices, particularly in all-solid-state secondary batteries.