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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. KEYWORDS fluorescent resin, phosphor, photocurable resin, stereolithography 3D printing, 1 | INTRODUCTION Three-dimensional (3D) printing technology [1-6] is a flexible and powerful advanced manufacturing technology that emerged in recent years. This technology has been widely used in numerous countries [...]

Herein, the performance of silicone-modified 3D printing photosensitive resin was examined. Bisphenol-A epoxy acrylate (EA) was used as the substrate and isophorone diisocyanate, hydroxy-silicone oil, and hydroxyethyl acrylate were used as the raw materials. A silicone intermediate was synthesized to modify the substrate to prepare the 3D printing photosensitive material. The as-synthesized materials were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. The tensile fracture morphology was also analyzed. The effects of the addition of silicone intermediates on the mechanical properties, thermal stability, and shrinkage of the prepared 3D printing photosensitive resins were investigated. The results showed that an organosilicone group was successfully introduced into the side chain of EA. When the ratio of n(silicone):n(EA) is 0.3:1, the material has a high impact strength of 19.4 kJ·m−2, which is 32.8% higher than that of the pure resin; in addition, the elongation at break is 8.65% (compared to 6.56% of the pure resin). The maximum thermal weight loss temperature is 430.33°C, which is 6°C higher than that of the pure resin.

Removal of Cu2+ ions from contaminated water is an important but challenging task. This study reports the synthesis of a composite hydrogel from two natural polysaccharides, namely, sodium alginate and chitosan, using inexpensive kaolin as a raw material and polyacrylamide as a modifier. The hydrogel had a high adsorption capacity and selectivity for Cu2+. The composite hydrogel was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. The pseudo-second-order kinetic model was the most suitable model for the kinetic results, and the Langmuir isotherm model was the most representative of the sorption system. The results revealed that the adsorption process was mainly controlled by chemisorption. The maximum adsorption capacity of the adsorbent was 106.4 mg·g−1. Therefore, this study presents a new perspective on the application of composite hydrogels as Cu2+ adsorbents.

Olfaction feedback systems could be utilized to stimulate human emotion, increase alertness, provide clinical therapy, and establish immersive virtual environments. Currently, the reported olfaction feedback technologies still face a host of formidable challenges, including human perceivable delay in odor manipulation, unwieldy dimensions, and limited number of odor supplies. Herein, we report a general strategy to solve these problems, which associates with a wearable, high-performance olfactory interface based on miniaturized odor generators (OGs) with advanced artificial intelligence (AI) algorithms. The OGs serve as the core technology of the intelligent olfactory interface, which exhibit milestone advances in millisecond-level response time, milliwatt-scale power consumption, and the miniaturized size. Empowered by robust AI algorithms, the olfactory interface shows its great potentials in latency-free mixed reality (MR) and fast olfaction enhancement, thereby establishing a bridge between electronics and users for broad applications ranging from entertainment, to education, to medical treatment, and to human machine interfaces.Liu et al. developed AI-driven, wearable olfactory interfaces with odor generators for realizing latency-free mixed-reality and fast olfaction recovery. This technology enables personalized olfactory feedback and enhanced virtual environments for various applications including education, and clinical treatment. [ABSTRACT FROM AUTHOR]

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]

The increased global demand for lithium is rapidly depleting the lithium ore reserves. Therefore, attention has turned to the recovery of lithium from aqueous solutions, such as lithium-containing brine. Compared with other methods of lithium recovery, adsorption is energy efficient and simple to implement, increasing demand for selective lithium adsorbents. In this study, a selective lithium-ion adsorbent, H4Ti5– x La x O12, was synthesized via the sol–gel method, followed by heat treatment and acid washing. The effects of the temperature and degree of lanthanum doping (x) on the crystalline phase, morphology, lithium-ion adsorption capacity, and lithium-ion selectivity of the ion sieve were investigated, and the optimal synthetic conditions were determined. We found that doping with La3+ cations (x = 0.01) increased the lithium-ion adsorption capacity (23.96 mg g−1 at 25 °C at pH = 12; 8.2% higher than before doping), rate, and selectivity. In addition, the ion sieve could be used over multiple adsorption–desorption cycles with only a minor reduction in the lithium-ion adsorption capacity (22.88 mg g−1). Overall, these results suggest that doping with La3+ cations stabilized the H4Ti5– x La x O12 crystal structure, alleviated particle agglomeration, expanded the lithium-ion channels, and decreased the resistance to lithium-ion migration, thus improving adsorption performance. The findings suggest that the proposed ion sieve has practical applications in the selective recovery of lithium from aqueous solutions containing a mixture of metal ions. [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]

Thin, soft, skin electronics have attracted great attention for their use in the fields of healthcare monitoring and human–machine interfaces. The power supply is always one of the key issues in skin electronics, as it provides electrical energy to sensors, wireless communication modules, chips, and so on. However, traditional batteries generally have limitations such as rigid formats, large volume, or even potential safety issues by hazard materials, which might not be applicable for skin electronics. Herein, we present an ultra-thin, soft and biocompatible sweat-activated battery, combining bio-inspired microfluidics with flexible electronic technologies. The sweat-activated battery can collect the human sweat in seconds and yield a power density up to 122 mW cm−2 and a discharge capacity of 8.33 mA h. The sweat-activated battery can provide sufficient power to drive the state-of-the-art wearable electronics for real-time monitoring physiological signals (including heart rate, blood oxygen and skin temperature) and wireless transmission to smartphones via Bluetooth. [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]

Here, the poly (l-lactic acid) (PLLA) membrane with multi-structured networks (MSN) is successfully prepared by electrospinning technology for the first time. It is composed of micron-sized ribbon-structured fibers and ultrafine nanofibers with a diameter of tens of nanometers, and they are connected to form the new network structure. Thanks to the special fiber morphology and structure, the interception and electrostatic adsorption ability for against atmospheric particulate matter (PM) are significantly enhanced, and the resistance to airflow is reduced due to the "slip effect" caused by ultrafine nanofibers. The PLLA MSN membrane shows excellent filtration performance with ultra-high filtration efficiency (>99.9% for PM 2.5 and >99.5% for PM 0.3 ) and ultra-low pressure drop (≈20 Pa). It has demonstrated filtration performance that even exceeds current non-biodegradable polymer materials, laying the foundation for future applications of biodegradable PLLA in the field of air filtration. In addition, this new structure also provides a new idea for optimizing the performance of other polymer materials., (© 2024 Wiley‐VCH GmbH.)