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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. This journal is

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]

The purpose of this study was to investigate whether the bone tunnel impaction technique performed by dilators could dwindle the tibial tunnel enlargement after anterior cruciate ligament (ACL) reconstruction with hamstring tendon using both extracortical suspensory fixation devices at femoral and tibial site.

Electrochromic smart windows (ESWs) can significantly reduce energy consumption in buildings, but their cost-effective, large-scale production remains a challenge. In this study, the instability of black phosphorus is leveraged to induce the growth of the tungsten oxide film through its decomposition process, inspired by the 2D material-assisted in situ growth (TAIG) method. This approach results in the preparation of large-scale, high-performance WO 3-x ·nH 2 O (n < 2) films. Characterization techniques and DFT calculations confirm efficient regulation of structural water and oxygen vacancies during TAIG preparation. The WO 3-x ·nH 2 O films exhibit excellent electrochromic (EC) properties, including high transmittance modulation (74.2%@1100 nm), fast switching time (t c  = 5.5 s, t b  = 3.8 s), high coloration efficiency (124.7 cm 2  C -1 ), and superior cyclic stability (transmittance modulation retained 94.7% after 20 000 cycles). Ultra-large WO 3-x ·nH 2 O film are prepared via a simple immersion process, and fabricated into a large-area ESW under facile laboratory conditions, demonstrating the economic and practical feasibility of this approach in industrial-scale production. Operated by the intelligent control circuit,  the ESW exhibits remarkable EC properties and cyclic stability This research represents a milestone in improving the performance and industrial-scale production of ESWs, bridging the gap to the commercialization of EC technology., (© 2024 Wiley‐VCH GmbH.)