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In this study, H4Ti5O12@CNT ion sieves with an encapsulated structure were fabricated by combining pretreated carbon nanotubes (CNTs) as a template and carbon source, C16H36O4Ti as a titanium source, and CH3COOLi as a lithium source. By characterizing and analyzing the pretreated and untreated CNTs, numerous COOH and OH functional groups were introduced into the pretreated CNTs, which improved their dispersion in aqueous solutions and ethanol and facilitated the adsorption of lithium ions. The ion sieves prepared with the precursor roasted at 700 °C showed the best adsorption performance. Moreover, the structural integrity of the ion sieves was not affected by acid washing. For the first adsorption cycle, the ion sieves had a lithium‐ion saturated adsorption capacity of 32.32 mg/g. After five adsorption–desorption cycles, the adsorption capacity only decreased by 5.1% to 30.68 mg/g, which shows that they had good cycling stability. [ABSTRACT FROM AUTHOR]

In this study, bisphenol A epoxy resin, 1,6‐Hexanediol diacrylate (HDDA), and 2,4,6‐Trimethylbenzoyl‐diphenylphosphine oxide (TPO) were utilized as a prepolymer, diluent, and photoinitiator, respectively, to prepare a light curing system with different amount of phosphor, which was used in place of conventional inorganic fillers. Phosphor was utilized to improve the precision of the material molded parts during the light curing process and enhance the mechanical properties of the molded parts owing to the ultraviolet (UV) absorption properties of phosphor, which prevented UV damage to the material, thus improving the light aging resistance and stability of the molded parts. Results revealed that the addition of 3% phosphor optimized the mechanical properties of the material (a maximum tensile strength of 42.43 MPa). Additionally, the material achieved the lowest linear (4.1%) and volumetric (0.58%) shrinkage at a phosphor content of 6%. This study provides a new insight into three‐dimensional (3D) printing resin for stereolithography and provides a reference for the improvement of 3D printing products. [ABSTRACT FROM AUTHOR]

Flexible and bio‐integrated electronics have attracted great attention due to their enormous contributions to personalized medical devices. Power sources, serving as one of the most important components, have been suffering from many problems, including deficient biocompatibility, poor stretchability, and unstable electrical outputs under deformed conditions, which limits the practical applications in flexible and bio‐integrated electronics. Here, we reported a fully stretchable magnesium (Mg)–air battery based on dual‐ions‐conducting hydrogels (SDICH). The high‐performance battery enables long‐term operation with lighting 120 lighting emitting diodes (LEDs) for over 5 h. Benefiting from the advanced materials and mechanical designs, the battery exhibits stability electrical outputs under stretching, which allows to operate ordinarily under various mechanical deformations without performance decay. Furthermore, the great biocompatibility of the battery offers great opportunity for biomedical applications, which is demonstrated by a self‐adaption wound dressing system. The in vitro and in vivo results prove that the self‐adaption wound dressing can effectively prevent wound inflammation and promote wound healing. By exploiting thermal feedback mechanics, the system can adjust antibiotic release rate and dosage spontaneously according to the real‐time wound conditions. The proposed fully stretchable Mg–air battery and self‐adaption wound dressing display great potential in skin‐integrated electronics and personalized medicine. [ABSTRACT FROM AUTHOR]

Multimodal force identification by electronic skin (E‐skin) provides comprehensive and precise tactile information that can enhance elaborated functions of fine tactile discrimination, robotic manipulation, and gesture recognition. However, it remains a great challenge to realize such complicated functions from a highly simplified E‐skin sensing system. Here, mimicking the multi‐mechanoreceptor synergistic effect in human skin, a simple, thin, soft, intelligent tactile sensor composed of an asymmetrically arrangement of strain sensing units array for multimodal tactile information decoding is reported. The E‐skin type tactile sensor exhibits good performance with excellent sensitivity for shear force (2.5 N–1), vertical force (0.11 kPa–1), that enables 3D force refactoring, as well as accurate recognition of sliding force for direction tracking. Another unique feature of the E‐skin type tactile sensor is the side force screen effect, that allows the tactile sensor to yield great accuracy and a gauge factor of 1492 in strain measuring. Furthermore, integration of the sensors into E‐skin array offers the capability of capturing dynamic and real‐time stress distribution on the hand in various conditions. This work provides a new route for complex force‐sensing from the simple structure and shows great potential in robotics, human‐machine interface, and virtual reality/augmented reality (VR/AR). [ABSTRACT FROM AUTHOR]

MXenes have received tremendous attention for flexible electronics owing to their excellent conductivity, water dispersibility, and mechanical flexibility. However, the sediment from the MXene production process is usually discarded as trash, resulting in low utilization. Here, we present a flexible pressure sensor that enables micro‐force sensing and efficient utilization of MXene by confining MXene trash among structured MXene electrodes. Benefiting from the synergistic effect of both the confined micro‐conical structure and easily changeable space of MXene trash, the as‐designed device can detect extremely subtle pressure of 2.9 Pa, deliver a high sensitivity over 4.08 kPa−1, and exhibit a remarkably fast response time (7 ms). These properties make it suitable for monitoring weak force signals from human wrist pulse and even for detecting dynamic responses associated with acoustic waves. This work provides a reference for the versatile and efficient application of MXene in the same device, showing great potential for sustainable production of next‐generation wearable smart electronics. [ABSTRACT FROM AUTHOR]

Drug release devices of small molecules are widely used in cell stimulation, drug delivery, and microenvironment regulation. Herein, a flexible drug release device (FDRD) powered by a triboelectric nanogenerator (TENG) is demonstrated, that has the superiority of low power consumption, flexible structure, and controllable release. In the self‐powered FDRD, the TENG can effectively harvest and transfer biomechanical energy into electricity. With a power management module, the TENG can provide a steady voltage supply for sustainable drug release, and the unique switchable wettability of poly(3‐hexylthiophene) films in Na2SO4 aqueous solutions can be regulated. The UV–vis absorption spectra of small molecules including methylene blue, fluorescein sodium, and rhodamine 6G released from the FDRD can be observed and recorded in real time. Furthermore, the releasing rate of conventional salicylic acid with the effect of removing cutin, sterilizing, and diminishing inflammation is also recorded in Na2SO4 aqueous solution. With the advantages of flexible structure, and controllable and sustainable release, the self‐powered FDRD is expected to find great potential in wearable medical devices, drug controllable release, and self‐powered therapy. [ABSTRACT FROM AUTHOR]

Multifunctional micro‐force sensing in one device is an urgent need for the higher integration of the smaller flexible electronic device toward wearable health‐monitoring equipment, intelligent robotics, and efficient human–machine interface. Herein, a novel microchannel‐confined MXene‐based flexible piezoresistive sensor is demonstrated to simultaneously achieve multi‐types micro‐force sensing of pressure, sound, and acceleration. Benefiting from the synergistically confined effect of the fingerprint‐microstructured channel and the accordion‐microstructured MXene materials, the as‐designed sensor remarkably endows a low detection limit of 9 Pa, a high sensitivity of 99.5 kPa−1, and a fast response time of 4 ms, as well as non‐attenuating durability over 10 000 cycles. Moreover, the fabricated sensor is multifunctionally capable of sensing sounds, micromotion, and acceleration in one device. Evidently, such a multifunctional sensing characteristic can highlight the bright prospect of the microchannel‐confined MXene‐based micro‐force sensor for the higher integration of flexible electronics. [ABSTRACT FROM AUTHOR]

A series of 2-substituted benzothiazoles (III) and (V) (28 examples in all) is readily prepared by a KI-catalyzed oxidative arylation of benzothiazoles (I) with corresponding aldehydes (II) and (IV), respectively. [ABSTRACT FROM AUTHOR]