Wearable electronics powered by flexible energy storage devices have captured global attention. Under low-temperature conditions, unfortunately, solidification of flexible hydrogel electrolyte and decreased pseudo-capacity of these devices largely hamper their practical use. In this study, photothermally-active Prussian blue (PB) was introduced onto poly(3,4-ethylenedioxythiophene)/polyacrylamide (PEDOT/PAM) networks to address the challenges of electrolyte solidification and degraded pseudo-capacitance for flexible all-in-one device at low temperatures. The as-constructed PB/PEDOT/PAM hydrogel device delivers stable electrochemical performance and remarkable mechanical property with 1652% elongation. Importantly, this hydrogel device well retains its flexibility in cold environment with a freezing point below −30 °C. The incorporation of PB extends the voltage range to 1.5 V as a single device, thus significantly enhancing the electrochemical performance as an all-in-one integrated device. Benefitting from the outstanding photo-to-thermal conversion ability of embedded PB nanocubes, the temperature of the assembled all-in-one PB/PEDOT/PAM device increased from −20 to 17.7 °C after solar-light irradiation for only 5 min. Moreover, the degraded pseudo-capacitance was subsequently boosted to 287.1% of its original capacitance at −20 °C. This study establishes a connection between flexible all-solid-state hydrogel devices and photothermally enhanced pseudo-capacitors in freezing environments, thereby expanding the potential applications of multi-functional pseudo-capacitors.

Chiral chemicals have attracted significant interest in the pharmaceutical industry, yet the separation methods to get pure enantiomers from racemic mixture are still challenging. To date, the separation of enantiomers still mainly depends on chromatography using high-cost chiral stationary phases. Herein, wood channels were used as the handheld integrated device, and enantiomer separation was simultaneously detected using an electrochemical detector. In this method, a chiral UIO-66 (L-UIO-66) modified enantiomer separation zone and carbonized wood based online detection zone are integrated along a single wood column. Based on the in situ separation results from the chronoamperometry data, the wood device shows excellent separation ability for a wide range of electrochemically active enantiomers, including 3,4-dihydroxyphenylalanine, amino acids, ascorbic acid, carnitine, and penicillamine with high chirality purity. The unbiased molecular dynamic simulations indicate that the excellent chiral recognition and separation are attributed to the different barriers from the bound states to the dissociated state of the enantiomers in the homochiral microenvironment of the framework. This integrated enantiomer separation-electrochemical detection device provides a novel, easy, and low-cost platform for the separation of pure enantiomer from racemic mixture.

Infectious diseases caused by bacteria are a global threat to the human health. Here, we propose a solvent "irrigation" technique to endow TiO₂ nanotubes (NTs) to precisely modify with functional nanomaterials, and apply them in constructing a near-infrared (NIR) light controlled drug-delivery system for rapid necrosis of bacteria. In this design, the NIR stimuli-responsive functional shell is located on the external tube wall of TiO₂ NT; the internal tube wall offers sufficient binding sites for drug loading. Using kanamycin as a model drug, we demonstrate that the reactive oxygen species generated in photocatalysis not only controllably release the loaded drug by scissoring the linked chains, but also effectively compromise bacteria membrane integrity by damaging the cell wall. Benefiting from the damages, antibiotics rapidly enter the bacteria and reach ≥99.9% reduction in Escherichia coli colony within only 2 h. Importantly, such a covalently conjugation-based delivery system can efficiently relieve radical-induced inflammation and cytotoxicity. This study provides an innovative design strategy for engineering delivery systems with tailorable components, enduring stimuli-response by multiple triggers.