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Reflective electrochromic devices (RECDs) based on polyaniline (PANI) have garnered significant attention due to their broad-band modulation capabilities. However, the inherent unstable molecular structure of PANI remains a major challenge, affecting both its cycling stability and modulation range. To address this issue, triphenylamine and m-phenylenediamine were introduced to prepare cross-linked PANI (CPANI) electrochromic thin films via a straightforward electrodeposition process in this paper. The thermal-infrared emissivity modulation range of the CPANI-based RECD (C-RECD) achieved great improvement in the atmospheric windows of 3–5 and 8–14 μm, with a maximum emissivity modulation range of 0.5 and 0.7, respectively. Remarkably, the C-RECD exhibits exceptional cycling stability, enduring up to 10 000 cycles, while maintaining a 70% average emissivity modulation range after cycling. The excellent modulation capability and cycling stability of the C-RECD break the record of the PANI-based RECDs. The theoretical calculations, in situ Raman spectroscopy, and emittance spectra were examined to gain insights into the crosslinking enhancement mechanism. Its distinctive cross-linked structure promotes electron delocalization within the PANI chain, which facilitates an increase in the number of polarons and hinders the formation of local quinoid over-oxidation units, thus effectively improving its emissivity modulation capability and cycling stability. The thermal-infrared images demonstrate the apparent temperature management effects at 7.2 °C and 13.3 °C when the C-RECD is integrated with human skin and a hot plate. This work provides promising opportunities for the production of long-term stable anti-reconnaissance and thermal management devices based on PANI-based RECDs. [ABSTRACT FROM AUTHOR]

To further broaden the applicable band of electrochromic devices, a counter electrode with electromagnetic wave absorption function was developed. A ferrosoferric oxide (Fe3O4)@Polyaniline (PANI) composite material with a core–shell structure was prepared by oxidative polymerization. The relative content of PANI and Fe3O4 and its impact on the electromagnetic wave absorption performance of the Fe3O4@PANI composite material were analyzed. The absorption bandwidth of the electromagnetic wave absorption counter electrode based on Fe3O4@PANI/polyvinylidene difluoride (PVDF) reached 3.5 GHz (14.5–18.0 GHz, RL < −10 dB), and it can provide a sufficient amount of counter ions to balance the charge of the electrochromic layer. The visible-infrared (VIS-IR) electrochromic device with an electromagnetic wave absorption function on the counter electrode exhibits color changes to yellow, green, and dark green on the side of the electrochromic layer, and has an emissivity change of 0.43 in the thermal infrared band wavelength range of 2.5–15 μm. The coloring and fading response times of the device are 5.9 s and 4.4 s, respectively, and the device maintains 95.7% of the initial current intensity after 1000 cycles. [ABSTRACT FROM AUTHOR]

Electrochromic smart windows (ESWs) hold great promise in improving energy efficiency in buildings. However, the production of large-scale ESWs still faces significant challenges due to equipment limitations and associated costs. This paper presents a simple, cost-effective, and environmentally friendly method for preparing Prussian blue (PB) films using a two-dimensional-material assisted in situ growth (TAIG) method. The growth mechanism of PB films prepared through the TAIG method was elucidated using SEM, TEM, and XPS characterization techniques. The PB films fabricated using the TAIG method demonstrate exceptional electrochromic properties, including multi-color modulation capabilities (colorless, blue, green, and yellow), a high optical modulation of 65.89% at 713 nm, fast switching times (5.9 s for coloring and 5.4 s for bleaching), and a high coloring efficiency of 81.73 cm2 C−1. Importantly, after 10 000 cycles, there was virtually no degradation of optical modulation of PB films. The electrochromic enhancement mechanism was elaborated in this paper. A comparison between PB films prepared via the TAIG method and the electrodeposition method was conducted using TG and GIWAXS tests. The PB films prepared through the TAIG method exhibit a low structural water content and a polycrystalline structure. DTF theoretical calculations were further carried out to confirm the lower band gap and great electron transition. Additionally, the successful fabrication of large-scale ESWs measuring 100 × 70 cm2 using the TAIG method demonstrates its practicality for industrial-scale production. Simulation studies of solar irradiation confirm the shielding capabilities of ESWs and their effectiveness in regulating indoor temperatures. In conclusion, this study represents a significant step towards the performance promotion and industrial-scale production of ESWs, contributing to the development of energy-efficient building solutions. [ABSTRACT FROM AUTHOR]

Hydrogels have been widely studied as promising materials in several applications, such as wearable devices, electronic skin, soft robot, artificial muscle and articular cartilage, due to their numerous prominent performances. However, the inferior mechanical property, especially difficult for hydrogels to simultaneously obtain high tensile strength and elongation, limits their further clinical application. Thus, here we used the multilayer and single layer graphene (MG and SG) as reinforcement fillers to improve the mechanical performances of neat polyvinyl alcohol (PVA) hydrogels. Our results showed that the high tensile strength and fracture elongation were simultaneously obtained from PVA/0.20wt%MG hydrogel, which were higher than those of PVA/SG hydrogel. Further, the elastic modulus of PVA/graphene composites was measured by calculating the effective modulus of SG and MG within PVA matrix from the Raman shift of D peak for the PVA/SG and PVA/MG composite hydrogel, respectively. The findings demonstrate the possibility of in situ exfoliation of MG in hydrogels under large tensile strain. [ABSTRACT FROM AUTHOR]

Quinoidal–aromatic conjugated polymers hold great application potential in organic field-effect transistors (OFETs). However, the development of high mobility quinoidal–aromatic conjugated polymers still lags behind the more popular donor–acceptor (D–A) conjugated polymers, mainly owing to the lack of a rational design strategy and efficient building block. Herein, a novel quinoid–donor–acceptor (Q–D–A) strategy is demonstrated to modulate the energy-level and boost the charge carrier transport mobility of conjugated polymers as opposed to the D–A system. On the basis of this strategy, a quinoidal–aromatic conjugated polymer, namely PAQM-BT, is designed and synthesized. With the combined use of quinoid, donor and acceptor units in the backbone, the resulting Q–D–A polymer PAQM-BT displays the narrowest bandgap with the deepest-lying lowest unoccupied molecular orbital (LUMO) energy level, highest backbone coplanarity, enhanced thin-film crystallinity and smallest effective hole mass in comparison with the corresponding D–A polymer PT3B1 and quinoid–donor (Q–D) polymer PAQM-3T. Benefitting from the more effective intra- and inter-chain charge transport, as corroborated by experiment and theoretical calculations, OFET devices based on PAQM-BT exhibit a highly boosted hole mobility of up to 5.10 cm2 V−1 s−1, which is one and four orders of magnitude higher than that of PAQM-3T and PT3B1, respectively, and is among the highest for quinoidal–aromatic conjugated polymers. The potent Q–D–A strategy not only allows the energy level to be modulated but also leads to effective charge carrier transport, opening up possibilities to the development of high mobility quinoidal–aromatic conjugated polymers based on a variety of quinoids, donors, and acceptors. [ABSTRACT FROM AUTHOR]

Flexible/wearable electrochromic zinc-ion battery (EC-ZIB) is considered to be promising smart multifunctional energy storage devices that monitor energy storage on the basis of their color variation. Herein, a self-doped PANI (SPANI) electrode has been prepared by a facile electrochemical copolymerization process. The prepared SPANI film exhibits a novel actiniae-like morphology, which is beneficial for electrolyte infiltration due to short ion diffusion pathways and fast electrochemical kinetics that ensure enhanced specific capacity. In a full all-in-one EC-ZIB device, the SPANI cathode provides a high specific capacitance of 180.5 mA h g−1 at 0.5 A g−1, excellent rate capability of 75.3% capacity retention even at a 20-fold current-density increase. The EC-ZIB possesses high energy and power densities (181.1 W h kg−1 @ 501.8 W kg−1 and 124.7 W h kg−1 @ 9148.6 W kg−1). At the same time, another positive is that the EC-ZIB has excellent electrochromic properties (light yellow, green and dark green) from 0.5 to 1.6 V. Therefore, its energy storage can be conveniently monitored according to color variation. The EC-ZIB efficiently combines multiple smart features, promoting the development of flexible intelligent energy storage devices. [ABSTRACT FROM AUTHOR]

Rotator cuff tears (RCTs), the most common tendon injury, are always accompanied by muscle atrophy, which is characterized by excessive protein degradation. Autophagy–lysosome systems are the crucial proteolytic pathways and are activated in atrophying muscle. Thus, inhibition of the autophagy–lysosome pathway might be an alternative way to minimize skeletal muscle atrophy. In this present study, combined with a tendon transection-induced rat model of massive rotator cuff tears, HE staining and transmission electron microscopy methods, we found leucine supplementation effectively prevented muscle atrophy, muscle injury and autophagosome formation. Utilizing immunoblotting, we discovered that leucine supplementation is able to inhibit the rise in autophagy-related protein expression (including LC3, Atrogin-1, MuRF1, Bnip3 and FoxO3) driven by tendon transection. The PI3K/AKT/mTOR pathway that was essential in autophagosome formation and autophagy was blocked in atrophying muscle and reactivated in the presence of leucine. Once administrated with LY294002 (PI3K inhibitor) and Rapamycin (mTOR inhibitor), leucine mediated by the anti-atrophic effects was nearly blunted. These results suggest that leucine potentially attenuates tendon transection-induced muscle atrophy through autophagy inhibition via activating the PI3K/AKT/mTOR pathway. [ABSTRACT FROM AUTHOR]

Chronic osteomyelitis is primarily caused by infection with Staphylococcus aureus (S. aureus). Antibiotics are commonly administered; however, it is a challenge to promote bone healing. The aim of this study was to investigate the in vitro effects of alkaloids from the herbal remedy Sophora flavescens (ASF) on rat calvarial osteoblasts (ROBs) infected with S. aureus and healthy osteoclasts. Cell proliferation and alkaline phosphatase, interleukin-6, and tumour necrosis factor-α activity was measured in infected ROBs; tartrate-resistant acid phosphatase was evaluated in osteoclasts via enzyme-linked immunosorbent assay. The mRNA and protein expression levels of bone morphogenetic protein 2, runt-related transcription factor 2, osteoprotegerin, and receptor activator of nuclear factor kappa-B ligand were assessed in infected ROBs through reverse transcription-polymerase chain reaction and western blotting analysis, respectively. Results indicated that ASF increased the viability of uninfected ROBs and infected ROBs treated with vancomycin via regulation of bone morphogenetic protein 2, runt-related transcription factor, osteoprotegerin, and receptor activator of nuclear factor kappa-B ligand mRNA and protein expression levels. In addition, the secretion of the inflammatory factor tumour necrosis factor-α was decreased and alkaline phosphatase activity was increased, inhibiting the viability of osteoclasts and tartrate-resistant acid phosphatase activity. Therefore, the herbal remedy ASF has potential as a new treatment for chronic osteomyelitis. [ABSTRACT FROM AUTHOR]

Flavonoids are the active component of the Herba Epimedii (H. Epimedii), which is commonly used in Asia. This study is to investigate the effect of H. Epimedii on bone repair after anti-infection treatment in vivo. The bioactive-composition group of H. Epimedii (BCGE) contained four flavonoids with the total content of 43.34%. Rabbits with chronic osteomyelitis in response to injection with Staphylococcus aureus were treated with BCGE of 242.70 mg/kg/day intragastrically after vancomycin-calcium sulphate treatment. Micro-computerd tomography (CT), morphology, blood biochemistry and osteocalcin levels were assessed for effect evaluation. In addition, the rat calvarial osteoblasts infected with S. aureus were treated with vancomycin and BCGE. Cell viability, alkaline phosphatase activity, bone morphogenetic protein 2, Runt-related transcription factor 2, osteoprotegerin, receptor activator of nuclear factor-κB ligand mRNA levels and protein expression were assessed. Our results indicated that BCGE promoted bone repair via increasing the bone mass, the volume of bone, promoting osteocalcin secretion after vancomycin-calcium sulfate treatment. BCGE enhanced the cell proliferation, by regulating bone morphogenetic protein 2, runt-related transcription factor 2, and osteoprotegerin/receptor activator of nuclear factor κ-B ligand mRNA and protein expression to maintain the balance between bone formation and bone resorption. Therefore, BCGE is a potential adjuvant herbal remedy for the post-infection treatment of chronic osteomyelitis. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]