Early Braking of Overwarmed Lithium-Ion Batteries by Shape-Memorized Current Collectors.

In the context of the constant impending energy crisis, the lithium-ion battery as a burgeoning energy storage means is showing extraordinary talents in many energy relevant investigations. However, fire and explosion would probably occur when the battery is encountered with overheating, at which the shrinking of the separator routinely causes an internal short circuit. Herein, we develop a kind of novel shape-memorized current collector (SMCC), which can successfully brake battery thermal runaway at the battery internal overheating status. Unlike traditional current collectors made of commercial copper foils, SMCC is made of a micropatterned shape memory micron-sized film with copper deposition. SMCC displays ideal conductivity at normal temperatures and turns to be insulative at overheating temperatures. Following this principle, the battery consisting of an SMCC can run normally at temperatures lower than 90 °C, while it quickly achieves self-shutdown before the occurrence of battery combustion and explosion.

Thermal Nociception of Ionic Skin: TRPV1 Ion Channel-Inspired Heat-Activated Dynamic Ionic Liquid.

The artificial reproduction of the tactile sensory function of natural skin is crucial for intelligent sensing, human-computer interaction, and medical health. Thermal nociception is an essential human tactile function to avoid noxious thermal stimuli, which depends on the specific heat-activation of the TRPV1 ion channel. Inspired by the TRPV1, a dynamic ionic liquid with heat-activation characteristics is designed and prepared, which can be activated at 45 °C, which is near the physiological noxious temperature, accompanied by a steep rise in electrical response signals. Its electrical behavior can be deemed to be the extreme version of temperature sensation similar to the natural thermal nociceptor. The heat-activation mechanism is confirmed as a feasible strategy to regulate the thermal response behavior of ions, and this reported dynamic ionic liquid has an unprecedented intrinsic temperature response sensitivity of up to 156.79%/°C. In consideration of the similarity between the heat-activated dynamic ionic liquid and the TRPV1 ion channel in terms of heat-activation characteristics, electrical output signal, and ultrathermal sensitivity, an all-liquid ionic skin with the ability of thermal nociception is further fabricated, which shows considerable potential to assist patients with tactile desensitization to avoid noxious thermal stimuli.

Solar activation of fungus coated in photothermal cloth.

Bioorthogonal reactions based on manipulating the physicochemical and biological behavior of natural cells have gained tremendous attention for meeting the demands for multifunctional microorganisms without decreasing cell viability. Described herein is a novel bioorthogonal method for microorganism (Aspergillus oryzae) modification which coats the microorganism with a photothermal conversion cloth for staying bioactive in cold environments. Two steps, including ferric ions primarily binding to the microorganism cell surface, followed by in situ polymerization of pyrrole, are adopted to actualize highly efficient polypyrrole modification on the microorganism surfaces. The production of α-amylase by Aspergillus oryzae and α-amylase catalytic ability are two representative indexes of cold adaptation as confirmed by a starch decomposition test. This strategy for coating microorganisms with photothermal cloth is biocompatible and cost-effective, and can achieve non-contact modulation, which also offers great promise for generating living cell-polymer hybrid structures based on other microorganism systems for low-temperature environmental adaptation.

Redox-Driven Spontaneous Double Emulsion.

The formation of spontaneous double emulsions is a peculiar phenomenon in emulsion systems. When compared to the traditional one-step and two-step methods for preparing double emulsions, spontaneous emulsification can not only steadily load uniform water droplets into an oil phase, but can also facilitate the preparation of emulsions with higher stability. However, the limited solubility of salts, which are typically used to modify osmotic pressure, in organic oils has inhibited the viability of this method for the preparation of W/O/W double emulsions. In this paper, a redox-driven spontaneous emulsification method is developed and investigated. Instead of employing oil-soluble salts, an oxidation reaction is implemented in the oil phase, which produces cation radicals and iodide counterions to generate osmotic pressure. Additionally, amphiphilic polymer chains are harnessed as stabilizers for the newly formed W/O interfaces. Various characterization methods have been used to elucidate the mechanism of both the oxidation reaction and the spontaneous formation of double emulsions.