Aerogel fibers with ultrahigh porosity, large specific surface area, and ultralow density have shown increasing interest due to being considered as the next generation thermal insulation fibers. However, it is still a great challenge to fabricate arbitrary aerogel fibers via the traditional wet-spinning approach due to the obvious conflict between the static sol–gel transition of the aerogel bulks and the dynamic wet-spinning process of aerogel fibers. Herein, a sol–gel confined transition (SGCT) strategy was developed for fabricating various mesoporous aerogel fibers, in which the aerogel precursor solution was first driven by the surface tension into the capillary tubes, then the gel fibers were easily formed in the confined space after static sol–gel process, and finally the mesoporous aerogel fibers were obtained via the supercritical CO2 drying process. As a typical case, the polyimide (PI) aerogel fiber prepared via the SGCT approach has exhibited a large specific surface area (up to 364 m2/g), outstanding mechanical property (with elastic modulus of 123 MPa), superior hydrophobicity (with contact angle of 153°), and excellent flexibility (with curvature radius of 200 μm). Therefore, the aerogel woven fabric made from PI aerogel fibers has possessed an excellent thermal insulation performance in a wide temperature window, even under the harsh environment. Besides, arbitrary kinds of aerogel fibers, including organic aerogel fibers, inorganic aerogel fibers, and organic–inorganic hybrid aerogel fibers, have been fabricated successfully, suggesting the universality of the SGCT strategy, which not only provides a way for developing aerogel fibers with different components but also plays an irreplaceable role in promoting the upgrading of the fiber fields.

A novel polyimide nanofibrous membrane with porous-layer-coated morphology has been successfully fabricated by an in situ self-bonding and micro-crosslinking technique.

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Nowadays, separators with superior properties have drawn widespread attention for the development of advanced and safe large-scale lithium-ion batteries (LIBs). Yet it is still a great challenge for improving overall the thermostability, flame endurance, wetting property, and ion-transport resistance of the polymer-based separators. Herein, a novel and green strategy is reported to address the aforementioned issue by means of the advanced nanostructured surface configuration design in which polyimide (PI) nanofibers are encapsulated by titania (TiO2) nanolayer via dipping in the titanium oxysulfate (TiOSO4) solution, which serves as the source of TiO2. Unlike conventional ceramics-coating methods, this distinctive TiO2@PI core–shell nanostructure is fabricated by the in situ hydrolysis deposition process, and the TiO2 nanoshell thickness can be controlled via simply changing the soaking time in TiOSO4 solution. After being encapsulated by the uniform TiO2 nanolayer, the PI-TiO2 core–shell separator manifests superior flame resistance, outstanding wettability for electrolyte, great thermal dimensional stability at 300 °C, higher glass transition temperature at 400 °C, and better ionic conductivity. Moreover, the cell installed in the PI-TiO2 core–shell separator displays brilliant cycling durability at 120 °C and high-rate property with as high as 82% capacity retention under 5 C (135 mAh g–1), which is superior to the cell using Celgard PP (60%, 90 mAh g–1) and PI nonwoven (75%, 123 mAh g–1). All the admirable features make PI-TiO2 nanofibrous membrane advanced and secure separator for large-scale power LIBs.

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Herein, an innovative polyimide (PI) nanofibrous membrane with unique bonding microstructures is fabricated for lithium‐ion battery (LIB) separator application via an elaborately designed dipping method using polyamic acid (PAA) glue as the joint binder. Furthermore, the bonding degree can be easily adjusted by simply varying the concentration of PAA glue. The introduction of bonding microstructures into the PI nanofibrous nonwoven membrane leads to the formation of tough 3D networks between PI nanofibers and turns the loose–weak nonwoven membrane to a compact–robust fabric membrane. The tensile strength of the PI nanofibrous membrane is consequently promoted from 5 to 36 MPa, which greatly improves the feasibility of the membrane for the LIB winding process and the safety of the LIB during long‐term running. The cells using the bonded PI nanofibrous separators exhibit an excellent cycling stability and rate capability, manifesting 80.3% capacity retention at 5 C (i.e., 128.5 mAh g−1) and can run stably at a high temperature of 120 °C. Herein, the prepared PI nanofibrous membranes with such bonding microstructures are demonstrated, which have the potential to be advanced separators for secure and high‐power LIBs.

A method for rapid identification and quantification of phthalate plasticizers in beverages was developed. A number of 15 phthalate plasticizers which covered all the phthalates concerned in the US Consumer Product Safety Improvement Act (CPSIA), European Union legislations and Chinese national standards (GB) were analyzed. By a combined solid-phase micro-extraction (SPME) and direct analysis in real time mass spectrometry (DART-MS) approach, phthalates at sub-ng•mL −1 levels can be qualitatively and quantitatively analyzed in a short time. The use of ultrahigh-resolving power and the accurate mass measurement capacity naturally provided by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) minimizes the matrix interferences and thus enables the evaluation of phthalates in a complex matrix without extensive sample handlings or preparations. The limits of quantification (LOQs) were estimated to be at 0.3-5.0 ng•mL −1 , lower than the Maximum Residue Limit (MRL) regulated by the European Union legislations (2007/19/EC) in foods, beverages, food packaging and toys (0.3-30 ng•mL −1 ). This rapid and easy-to-use SPME-DART-FT-ICR-MS method provided a relatively high-throughput and powerful analytical approach for quick testing and screening phthalates in beverages and water samples to ensure food safety.

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