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This paper describes the preparation and properties of PVDF/P(hexafluorobutyl methacrylate-copoly(ethyleneglycol)methacrylate)(P(HFBMA-co-PEGMA)) blend gel polymer electrolyte (GPE) for highperformance lithium-ion batteries. The fluorinated amphiphilic copolymer, P(HFBMA-co-PEGMA), was synthesized by simple radical polymerization and then blended into poly(vinylidene fluoride) (PVDF) matrix via immersion phase inversion process. The composition, morphologies, liquid electrolyte uptake of the blend membranes and electrochemical properties of the corresponding GPEs were systematically investigated. It is found that the introduction of P(HFBMA-co-PEGMA) results in a slight increase in porosity, a reduction in crystallinity and better affinity with liquid electrolyte, which consequently lead to a substantial increase in liquid electrolyte uptake and ion conductivity. For the membrane with P(HFBMA-co-PEGMA)/PVDF mass ratio in 1.7/10, the liquid electrolyte uptake and ionic conductivity reach to 387% and 3.19 mS cm À1 , respectively. In addition, the resulting GPE is electrochemically stable up to about 4.5 V (vs. Li + /Li).

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Engineering hierarchical structures of electrode materials is a powerful strategy for optimizing the electrochemical performance of an anode material for lithium-ion batteries (LIBs). Herein, we report the fabrication of hierarchical TiO2/C nanocomposite monoliths by mediated mineralization and carbonization using bacterial cellulose (BC) as a scaffolding template as well as a carbon source. TiO2/C has a robust scaffolding architecture, a mesopore-macropore network and TiO2-C heterostructure. TiO2/C-500, obtained by calcination at 500 °C in nitrogen, contains an anatase TiO2-C heterostructure with a specific surface area of 66.5 m(2) g(-1). When evaluated as an anode material at 0.5 C, TiO2/C-500 exhibits a high and reversible lithium storage capacity of 188 mA h g(-1), an excellent initial capacity of 283 mA h g(-1), a long cycle life with a 94% coulombic efficiency preserved after 200 cycles, and a very low charge transfer resistance. The superior electrochemical performance of TiO2/C-500 is attributed to the synergistic effect of high electrical conductivity, anatase TiO2-C heterostructure, mesopore-macropore network and robust scaffolding architecture. The current material strategy affords a general approach for the design of complex inorganic nanocomposites with structural stability, and tunable and interconnected hierarchical porosity that may lead to the next generation of electrochemical supercapacitors with high energy efficiency and superior power density.

Circularly polarized room‐temperature phosphorescence (CPRTP) is of paramount importance for applications in information encoding, bioimaging, and optoelectronic devices, however, it remains challenging to organize highly efficient CPRTP materials with controlled handedness and long afterglow. Herein, as an outstanding novel finding, it is diclosed that ultralong CPRTP with on‐demand chiroptical properties is simple to realize using the earth‐abundant cellulose and silica. It is shown that left‐handed chiral nematic nanoporous silica films featuring defect photoluminescence enable ultralong CPRTP with an unprecedented control of the handedness. This work presents that the chiral nematic nanoporous silica films display right‐handed CPRTP and left‐handed CPRTP with the phosphorescence dissymmetry factors up to −0.130 and 0.093 as well as the afterglow lifetimes of 1.094 and 0.949 s, respectively. The potential of the transparent chiral nematic nanoporous silica films, capable of ultralong CPRTP and selective reflection of left‐handed circularly polarized light, for the development of anticounterfeiting optical labels is showcased. This work presents a versatile strategy and a step toward the development of ultralong CPRTP materials with on‐demand chiroptical properties from readily available defect phosphors for photonic applications.