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Stretchable electrodes are critical to the development of advanced technologies such as human–machine interaction, flexible sensing, and wearable power supply, making them of significant research value. However, the current preparation methods for high‐performance stretchable electrodes are complex and inefficient, posing challenges for their large‐scale application in the realm of flexible wearables. To address this need, a straightforward and efficient embedding strategy is reported for fabricating stretchable silver nanowire/thermoplastic elastomer composite electrodes (referred to as Strem‐AT) utilizing the viscoelasticity and outstanding mechanical properties of polymer elastomers to achieve outstanding extensibility, conductivity, and a smooth surface. These electrodes exhibit excellent tensile behavior, low surface roughness, and stable electrical properties, enabling their successful integration into stretchable sensors and intrinsically stretchable organic photovoltaic cells (IS‐OPV). When applied to human skin joints for motion detection, the sensor demonstrates remarkable stretchability and stable signal output. Importantly, the all‐polymer IS‐OPV exhibits a top‐notch power conversion efficiency (PCE) of >12.5% and a PCE80% strain exceeding 50%. Furthermore, even after subjecting high‐strain stretching at 50% for 1000 cycles, the IS‐OPV can retain 76% of the initial PCE. This study presents a multifunctional stretchable electrode with high repeatability and easy‐to‐scale fabrication in wearable sensors and photovoltaics. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: With the emergence of Y‐series small molecule acceptors, polymerizing the small molecule acceptors with aromatic linker units has attracted significant research attention, which has greatly advanced the photovoltaic performance of all‐polymer solar cells. Despite the rapid increase in efficiency, the unique characteristics (e. g., mechanical stretchability and flexibility) of all‐polymer systems were still not thoroughly explored. In this work, we demonstrate an effective approach to simultaneously improve device performance, stability, and mechanical robustness of all‐polymer solar cells by properly suppressing the aggregation and crystallization behaviors of polymerized Y‐series acceptors. Strikingly, when introducing 50 wt% PYF‐IT (a fluorinated version of PY‐IT) into the well‐known PM6:PY‐IT system, the all‐polymer devices delivered an impressive photovoltaic efficiency of 16.6%, significantly higher than that of the control binary cell (15.0%). Compared with the two binary systems, the optimal ternary blend exhibits more efficient charge separation and balanced charge transport accompanying with less recombination. Moreover, a high‐performance 1.0 cm2 large‐area device of 15% efficiency was demonstrated for the optimized ternary all‐polymer blend, which offered a desirable PCE of 14.5% on flexible substrates and improved mechanical flexibility after bending 1000 cycles. Notably, these are among the best results for 1.0 cm2 all‐polymer OPVs thus far. This work also heralds a bright future of all‐polymer systems for flexible wearable energy‐harvesting applications. [ABSTRACT FROM AUTHOR]

Multi-view 3D human pose estimation (HPE) currently faces several key challenges. Information from different viewpoints exhibits high variability due to complex environmental factors, posing difficulties in cross-view feature extraction and fusion. Additionally, multi-view 3D labeled pose data is rather scarce, and the impact of input 2D poses on 3D HPE accuracy has received little attention. To address these issues, we propose an E rror-aware S elf-supervised transformer framework for M ulti-view 3D HPE (ESMformer). Firstly, we introduce a single-view multi-level feature extraction module to enhance pose features in individual viewpoints, which incorporates a novel relative attention mechanism for representative feature extraction at different levels. Subsequently, we develop multi-view intra-level and cross-level fusion modules to exploit spatio-temporal feature dependencies among human joints, and progressively fuse pose information from all views and levels. Furthermore, we explore an error-aware self-supervised learning strategy to reduce the model's reliance on 3D pose annotations and mitigate the impact of incorrect 2D poses. This strategy adaptively selects reliable input 2D poses based on 3D pose prediction errors. Experiments on three popular benchmarks show that ESMformer achieves state-of-the-art results and maintains cost-effective computational complexity. Notably, ESMformer does not rely on any 3D pose annotations or prior human body knowledge, making it highly versatile and adaptable in practical applications. 1 1 The code and models are available at https://github.com/z0911k/ESMformer. • We develop a novel transformer-based multi-view 3D HPE framework (ESMformer). It hierarchically integrates single-view multi-level pose feature extraction with progressive feature fusion across viewpoints and levels. By mining out meaningful multi-level information from multiple viewpoints, ESMformer effectively enriches pose feature expression. • We design a simple yet effective relative attention mechanism to model the spatial dependencies among all human joints, significantly enhancing the pose feature representations and making the feature more robust and adaptable to changes in viewpoints and environmental conditions. • We explore an error-aware self-supervised learning strategy that reduces the model's reliance on 3D pose annotations and mitigates the impacts of incorrect 2D poses. This strategy utilizes the prediction errors of 3D poses to guide the selection of reliable 2D poses. • ESMformer achieves state-of-the-art results on three typical 3D HPE benchmarks. It significantly alleviates depth ambiguity and improves 3D HPE performance while maintaining a cost-effective computational complexity, without requiring any 3D pose annotations. [ABSTRACT FROM AUTHOR]

The rapid development of low bandgap polymer acceptors has promoted the efficiency up to ≈17% for all‐polymer solar cells (all‐PSCs). Nevertheless, the polymeric blend film, core to the photoelectric conversion of all‐PSCs, has not been thoroughly understood in terms of the influence and regulatory factors of mechanical properties, which hinders the advances in flexible and wearable applications. Herein, a range of characterization methods is combined to investigate the mechanical properties, miscibility, and film microstructure of the blends based on several representative polymer donors (PTzBI‐Si, PTVT‐T, PM6 and PTQ10) and a benchmark polymer acceptor N2200, and to further reveal the miscibility‐property relationships of the miscibility property. The results stress that fracture behaviors and elastic moduli of these blends with varied compositions show different changing trends, which are affected by molecular interactions and aggregated structure of the blends. The elastic moduli of the four all‐polymer blends can be nicely predicted by different models that are deduced from macromolecular mechanics. Most crucially, the correlations between elastic modulus, morphology, and miscibility of all‐polymer blends are elucidated for the first time. The derived relationships is validated with another high‐efficiency blend and will be the key to the successful fabrication of mechanically robust and stretchable all‐PSCs with high efficiency. [ABSTRACT FROM AUTHOR]

The progress of stretchable and wearable photovoltaics relies heavily on intrinsically stretchable active layer films. Nevertheless, there is a paucity of research clarifying the connections between their microstructure, performance, and their adaptation to large strain in polymer electronic films. The current study utilizes multiple synchrotron X‐ray scattering methods to collectively examine the correlations between morphology and stretchability, as well as the microstructural evolution induced by stretching in three sample cases of highly stretchable ternary blend films. These blends contain over 30% by weight of a polymer elastomer, such as styrene‐ethylene‐butylene‐styrene block copolymer, integrated into the high‐performance polymer:nonfullerene small molecule mixture. Specifically, the real‐time microstructural changes of these durable organic photovoltaic films with elastomers are monitored when subjected to tensile stretching through in situ synchrotron X‐ray scattering. The experiments demonstrate that polymeric elastomers can effectively lower the degree of crystallinity in films and deform the crystallites of semiconductor molecules. The elastomeric component aids in stress dispersion during stretching, thereby improving the microstructural durability of blend films. This study provides new recommendations for advancing stretchable organic optoelectronic devices. [ABSTRACT FROM AUTHOR]

• The hot tearing susceptibility of camshaft castings was studied. • The Clyne-Davies model was improved. • A new evaluation model of hot tearing susceptibility was proposed. • Crack source was caused by excessive non-equilibrium solidification of castings. • The countermeasures were proposed to reduce the probability of crack formation. As a widely used cyclical motion component, the camshaft plays a key role in the accuracy and stability of the whole machine. Micro hot cracks in the camshaft casting process are an important cause of failure in subsequent machining and operation. In this paper, the hot tearing susceptibility of the camshaft in the casting process was studied using the alloy composition (carbon equivalent and Mn/S ratio) and mold preheating temperature. The formation mechanism of the hot tear source was analyzed through the microscopic morphology of the fracture-sensitive cross-section. Using the improved Clyne-Davies model and the newly proposed hot tearing susceptibility (HTS) model, the results show that as the carbon equivalent and Mn/S ratio increase, the hot tearing susceptibility of the camshaft first decreases and then increases. The hot tearing tendency of the casting can be reduced by appropriately increasing the mold preheating temperature. The microscopic morphology indicates that the initiation and propagation of the crack source are caused by the excessively serious non-equilibrium solidification of the camshaft metal fluid. Finally, potential countermeasures are proposed to decrease micro hot cracks in camshaft castings, including the adjustment of alloy composition, optimization of casting process parameters, and improvement of system solidification conditions. [ABSTRACT FROM AUTHOR]

Background: Studies have shown that the absence of bile in the gut lumen, either by bile duct ligation or bile diversion, induces mucosal injury. However, the mechanism remains elusive. In this study, the role of bile pigments in gut barrier function was investigated in a rat model of bile duct ligation. Methods: Male Sprague Dawley (SD) rats were used in this study. After ligation of bile duct, the animals were administrated with free bilirubin, bilirubin ditaurate, or biliverdin by intragastric gavage. 1, 2, or 3 days later, the animals were sacrificed and the damage of mucosa was assessed by histological staining as well as biochemical parameters such as changes of diamine oxidase (DAO) and D-lactate (D-Lac) in the blood. Trypsin and chymotrypsin of the gut were also measured to determine how these digestive proteases may relate to the observed effects of bile pigments. Results: Bile duct ligation (BDL) caused significant increases in gut trypsin and chymotrypsin along with damage of the mucosa as demonstrated by the histological findings under microscope, the reduced expression of tight junction molecules like occludin, and significant changes in DAO and D-lac in the blood. Free bilirubin but not bilirubin ditaurate or biliverdin showed significant inhibitions on trypsin and chymotrypsin as well as alleviated changes of histological and biochemical parameters related to gut barrier disruption. Conclusion: Bile may protect the gut from damage through inhibiting digestive proteases like trypsin and chymotrypsin by free bilirubin. [ABSTRACT FROM AUTHOR]

To improve the comprehensive mechanical properties of Mg-15Al magnesium alloy, different amounts (from 0 to 4.0wt.%) of Nd were added to the alloy and six Mg-15Al-xNd alloys were prepared by metal mould casting. The effect of Nd content on microstructure of the alloys was investigated by means of OM, SEM, EDS, TEM, and XRD. The tensile properties were tested at room temperature (RT) and high temperature (473 K). The results indicate that the primary α-Mg dendrite is significantly refined with the addition of Nd. The best refinement is reached at 1.0wt.% Nd content and the average dendrite arm spacing decreases from 80- 100 pm (without Nd addition) to ∼20 μm. A further increase in Nd content leads to the coarsening of the primary α-Mg dendrite. The addition of Nd improves the tensile properties of Mg-15Al both at RI and 473 K. The Mg-15Al alloy containing 1.0wt.% Nd exhibits the best tensile properties. Compared with the alloy without Nd, the yield and ultimate tensile strength of the Mg-15Al-1.0Nd alloy at RT increase from 132.3 to 148.6 MPa and 152.3 to 189.6 MPa, increase by 12.3% and 24.5%, respectively; and the elongation at RT increases from 0.05 % to 1.24%. The yield and tensile strength of the alloy at 473 K increase from 97.9 to 115.3 MPa and 121.6 to 140.1 MPa, increase by 15.2% and 20%, respectively. Further increment of Nd content to 1.5wt.% degrades the tensile properties, which is ascribed to grain coarsening and growth of the Al-Nd phase. [ABSTRACT FROM AUTHOR]

Abstract: The effect of the addition of 0.5wt% Sb and equal channel angular pressing (ECAP) on the microstructures and mechanical properties of Mg–10Al alloy was investigated. The results show that the addition of Sb has little effect on the as-cast microstructures of the alloy except for encouraging the formation of rod-shaped Mg3Sb2 particles. However, the microstructures of the Sb-alloyed Mg–10Al alloy were greatly improved after ECAP processing. The coarse rod-shaped Mg3Sb2 particles are broken into finer particles during ECAP, which then hinder the grain growth and thereby enhance the refinement function of ECAP processing on the α-(Mg) matrix and the β-Mg17Al12 phase. Relative to the as-cast alloys and as-ECAPed Mg–10Al, the as-ECAPed Mg–10Al–0.5Sb alloy exhibited superior mechanical properties at both room temperature and elevated temperatures due to the alloy structure optimization as a result of the combination of Sb-alloying and ECAP processing. [Copyright &y& Elsevier]

Flexible strain sensors capable of acquiring tiny mechanical signals and attaching to various irregular surfaces are becoming prevalent in physiological measurement, soft robotics, and human‐machine interaction. However, the advancement of flexible strain sensors is substantially impeded by the intrinsic compromise between sensitivity and the range of detectable signals. Inspired by the multilayer structure of nacre in nature, a carbon nanotubes (CNTs)/graphene (GR)/graphene (GR)/thermoplastic polyurethane (TPU) mat (CGGTM) is prepared by electrospinning and high‐pressure spraying technology. By designing a multilayer structure with mutually non‐interfering conductive networks, the resulting CGGTM possesses a low detection limit (0.05% strain), high sensitivity (gauge factor, GF > 152537), large detection range (up to 364% strain), fast response/recovery time (80 ms/100 ms), and excellent cyclic durability (up to 1000 cycles). Furthermore, the CGGTM also exhibits satisfactory triboelectric performances when assembled into a triboelectric nanogenerator (TENG, 3 × 3 cm2), including high triboelectric output (open‐circuit voltage Voc = 135.4 V, short‐circuit current Isc = 1.25 µA) and power density (88 mW m−2), enabling reliable power supply, self‐powered sensing, and pulse monitoring capability. Finally, CGGTM is successfully applied to the collection of biological signals and multi‐gesture motion recognition assisted by machine learning algorithms, which holds promise for intelligent interaction with gestures in the future. [ABSTRACT FROM AUTHOR]

Concurrently achieving high efficiency, mechanical robustness and thermal stability is critical for the commercialization of all‐polymer solar cells (APSCs). However, APSCs usually demonstrate complicated morphology, primarily attributed to the polymer chain entanglement which has a detrimental effect on their fill factors (FF) and morphology stability. To address these concerns, an end‐group extended polymer acceptor, PY‐NFT, was synthesized and studied. The morphology analysis showed a tightly ordered molecular packing mode and a favorable phase separation was formed. The PM6 : PY‐NFT‐based device achieved an exceptional PCE of 19.12 % (certified as 18.45 %), outperforming the control PM6 : PY‐FT devices (17.14 %). This significant improvement highlights the record‐high PCE for binary APSCs. The thermal aging study revealed that the PM6 : PY‐NFT blend exhibited excellent morphological stability, thereby achieving superior device stability, retaining 90 % of initial efficiency after enduring thermal stress (65 °C) for 1500 hours. More importantly, the PM6 : PY‐NFT blend film exhibited outstanding mechanical ductility with a crack onset strain of 24.1 %. Overall, rational chemical structure innovation, especially the conjugation extension strategy to trigger appropriate phase separation and stable morphology, is the key to achieving high efficiency, improved thermal stability and robust mechanical stability of APSCs. [ABSTRACT FROM AUTHOR]

Stretchable, flexible, and strain‐sensitive hydrogels have gained tremendous attention due to their potential application in health monitoring devices and artificial intelligence. Nevertheless, it is still a huge challenge to develop an integrated strain sensor with excellent mechanical properties, broad sensing range, high transparency, biocompatibility, and self‐recovery. Herein, a simple paradigm of stretchable strain sensor based on multifunctional hydrogels is prepared by constructing synergistic effects among polyacrylamide (PAM), biocompatible macromolecule sodium alginate (SA), and Ca ion in covalently and ionically crosslinked networks. Under large deformation, the dynamic SA‐Ca2+ bonds effectively dissipate energy, serving as sacrificial bonds, while the PAM chains bridge the crack and stabilize the network, endowing hydrogels with outstanding mechanical performances, for instance, high stretchability and compressibility, as well as excellent self‐recovery performance. The hydrogel is assembled to be a transparent and wearable strain sensor, which has good sensitivity and very wide sensing range (0–1700%), and can precisely detect dynamic strains, including both low and high strains (20–800% strain). It also exhibits fast response time (800 ms) and long‐time stability (200 cycles). The sensor can monitor and distinguish complicated human motions, opening up a new route for broad potential applications of eco‐friendly flexible strain‐sensing devices. [ABSTRACT FROM AUTHOR]

Intrinsically stretchable organic photovoltaic cells (OPVs) have garnered significant attention as crucial devices for powering next‐generation wearable electronics. Despite the rapid power conversion efficiency gains in champion OPVs, their brittle stretchability has failed to meet the demands of the Internet of Things era, severely hindering further development and practical applications. In this regard, a new dual‐donor polymer blending strategy is demonstrated for constructing intrinsically stretchable OPVs by designing a novel high‐molecular–weight conjugated polymer PM6‐HD. This PM6 derivative featuring long alkyl chains can reach a sufficiently high molecular weight and thus exhibits a high fracture strain exceeding 90%, which is ≈12 times higher than the benchmark PM6. Synergistic optimization of mechanical properties and photovoltaic performance in polymer:small molecule and all‐polymer systems constructed from the physical blends of PM6 and PM6‐HD is achieved. Crucially, the resulting intrinsically stretchable OPV demonstrates excellent stretchability and stability, with a record PCE80% strain of 50.3% and the efficiency retention of above 80% even after 1000 cycles of cyclic stretching at high strains. This work contributes to the advancement of intrinsically stretchable OPV technology and opens up new possibilities for its integration into wearable electronic devices. [ABSTRACT FROM AUTHOR]

In this paper, a numerical simulation method based on the camshaft casting process and crack expansion was proposed to study the propagation characteristics of casting hot cracks. The dynamic visualisation process of hot crack growth indicates that the formation of hot tear is dominated by opening mode cracks. And during the propagation process, the equivalent stress intensity factor at the crack front first decreases and then increases. Furthermore, the propagation characteristics of the crack under different hot tear initiation conditions were studied by this method. The results reveal that the expansion ability of a hot crack is affected by the equilibrium solidification scale, solidification sequence, and solidification path of the casting. Finally, using the microscopic morphology of the cracks, the semi-quantitative analysis of the elements illustrates that the carbon content decreases sharply at the crack formation site, while manganese and sulphur are relatively rich. [ABSTRACT FROM AUTHOR]

• CB particles were decorated on PDMS foam to fabricate a flexible porous piezoresistive sensor. • The sensor possesses a very high linear working range (up to 91%). • A fast response time (45 ms) and superior durability (>15000 cycles) have both been achieved. • The sensor possess an excellent hydrophobic property (water contact angle up to 149°). • The CB/PDMS foam can also be used for oil/water separation. The achievement of favorable pressure sensor integrated with large linear working range, high sensitivity and excellent response durability is still a great challenge for flexible and wearable piezoresistive materials. In this paper, a facile and scalable strategy is proposed to fabricate a porous foam sensor based on carbon black/polydimethylsiloxane (CB/PDMS). CB particles were decorated onto the surface of the cell walls and some particles were embedded into PDMS matrix after the ultrasonication treatment. The density and porosity of the foam are 0.13 g/cm3 and 76.1%, respectively. A very high linear working range (up to 91%), an excellent response stability, a fast response time (45 ms), and a superior durability (>15000 cycles) are achieved synchronously. Here, the large linear sensing range is mainly related to the nice CB conductive network on the cross-linked PDMS foam and the high modulus and elasticity of the composite material, which ensure the homogeneous deformation of the foam under compression. It is worth noting that the response behavior of CB/PDMS foam is maintained well even in water owing to its excellent hydrophobic property (water contact angle up to 149°), indicating that this material can be used as a waterproof piezoresistive sensor. Our CB/PDMS foam is then assembled as a wearable sensor, and it exhibits nice capability of monitoring human body motions, such as the bending of fingers and elbow, walking, jumping and squatting, etc. The porous foam sensor also has a good oil/water separation ability, showing a multifunctional characteristic. [ABSTRACT FROM AUTHOR]

The emerging solution‐based solar cells and photodetectors have gained worldwide research interest over the past decades. Hole transport materials (HTMs) have greatly advanced the progress of these solution‐based electronics. Nevertheless, developing low‐cost and efficient HTMs is far from satisfactory. In this contribution, poly(3‐pentylthiophene) (P3PT) is introduced as a facile, low‐cost, and versatile dopant‐free polymer HTM for both quantum dot (QD) and perovskite electronic devices. Compared to the broadly used poly(3‐hexylthiophene), P3PT presents the reduced molecular aggregation and preferential face‐on orientation, which can markedly enhance the hole‐carrier transport in optoelectronic devices. Accordingly, P3PT can deliver the substantial improvement of photovoltaic performance from ∼8.6% to ∼9.5% for QD/polythiophene solar cells and from ∼16% to ∼18.8% for perovskite/polythiophene solar cells, which are both among the topmost values in the corresponding fields. Furthermore, P3PT HTMs can also significantly enhance the photodetection performance of QD and perovskite photodetectors by a factor of ∼3, indicating its great application potential in a variety of emerging optoelectronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • A carbon nanotubes (CNTs)/carbon black (CB)/polydimethylsiloxane (PDMS) sponge with porous and microdome dual microstructures was prepared. • The CCPMH-based flexible pressure sensor possesses high sensitivity (7.10 kPa−1) and a wide sensing range (more than 350 kPa). • The synergistic effect of the dual sensing mechanisms on the sensing performances is discussed in detail. • The flexible pressure sensor is demonstrated for the applications of human motion detection and sitting position discrimination. The application fields of flexible pressure sensors are constantly expanding benefiting from their characteristics of being lightweight, flexible, easy to install, etc. Various structures have been developed for the purpose of improving the sensing performances of these sensors. However, the traditional structure designs typically enhance only a single aspect of performance. In this study, a flexible pressure sensor based on carbon nanotubes (CNTs)/carbon black (CB)/polydimethylsiloxane (PDMS) conductive sponge (CCPS) with both porous and microdome dual microstructures is prepared through the double template and swelling ultrasound methods. The introduction of two microstructures leads to the synergistic effect of dual sensing mechanisms, and the dual sensing mechanisms have been discussed according to the changes in microstructure morphology and finite element analysis results. Thanks to the synergistic effect of dual sensing mechanisms, CCPS exhibits comprehensive pressure sensing performances including a wide pressure sensing range of more than 350 kPa, high sensitivity under low pressure (7.10 kPa−1 over 0–25 kPa, 2.96 kPa−1 over 25–135 kPa, 1.09 kPa−1 over 135 kPa), and satisfactory long-term using performance of over 2000 cycles. CCPS is finally demonstrated for applications such as human motion detection, Morse code, and sitting position discrimination, indicating its broad application possibilities. [ABSTRACT FROM AUTHOR]

All‐polymer solar cells (all‐PSCs) are one of the most promising application‐oriented organic photovoltaic technologies due to their excellent operational and mechanical stability. However, the power conversion efficiencies (PCEs) are mostly lower than 16%, restricting their core competitiveness. Furthermore, the improvement of mechanical durability is rarely paid attention to cutting‐edge all‐PSCs. This work deploys a low‐cost "technical grade" PCBM (incompletely separated but pure mixtures containing ≥90% [70]PCBM or [60]PCBM), into the efficient PM6:PY‐IT all‐polymer blend, successfully yielding a high‐performance ternary device with 16.16% PCE, among the highest PCE values for all‐PSCs. Meanwhile, an excellent mechanical property (i.e., crack onset strain = 11.1%) promoted from 9.5% for the ternary system is also demonstrated. The "technical grade" PCBM slightly disrupts the crystallization of polymers, and disperses well into the amorphous polymer regions of the all‐PSC blends, thus facilitating charge transport and improving film ductility simultaneously. All these results confirm introducing low‐cost "technical grade" PCBM with high electron mobility into all‐polymer blends can improve carrier mobility, reduce charge recombination, and optimize morphology of the amorphous polymer regions, thus yielding more efficient and mechanically durable all‐PSCs. [ABSTRACT FROM AUTHOR]

The emerging solution‐processed solar cells have attracted worldwide effort in the last decade. Developing efficient, stable, and cost‐effective solar cells is strongly desirable in countering the growing global warming. Nevertheless, the photovoltaic performance and stability of hybrid solar cells based on low‐cost polythiophenes are far from satisfactory, due to their high‐lying energy levels and excessive aggregation. Herein, it is shown that brominated polythiophene (P3HT‐Br), prepared via a facile two‐step approach can effectively facilitate charge transport and suppress recombination in quantum dot (QD)/organic heterojunctions. Accordingly, the power conversion efficiency of the optimized hybrid polythiophene/QD cell is boosted from 8.7% to 11% (a 26% increase) with markedly reduced energy loss. More strikingly, the device achieves record‐high thermal stability with a lifetime of over 400 h maintaining 80% of the initial performance. Both device efficiency and stability are the best reported for polythiophene/QD hybrid solar cells. Moving forward, brominated polythiophenes hold great application in perovskite solar cells with significantly improved performance and offer new opportunities for other emerging solar cells. [ABSTRACT FROM AUTHOR]

• A flexible CB/TPU foam with a pinnate-veined aligned porous structure was prepared. • The foam can both serve as a flexible strain sensor and an adsorption material. • The foam sensor has excellent sensing discernibility and high sensitivity. • The sensor exhibits superior response stability in a wide sensing range. In this paper, flexible conductive carbon black (CB)/thermoplastic polyurethane (TPU) foam (CTF) with an intriguing pinnate-veined aligned porous structure was fabricated via a unidirectional freeze-drying process. The density, porosity and average pore size of the composite foam are 0.13 g cm−3, 83.7% and 24.9 μm, respectively. CB particles are uniformly dispersed in the skeleton of the as-prepared foam, resulting in a low percolation threshold of 0.48 vol%. The CTF is capable of distinguishing different compressive strain by change of the relative resistance. Its responsive behaviors towards compressive strain present an excellent linear characteristic with a high gauge factor (GF) up to 1.55. In the piezoresistive tests, the CTF shows a fast response/relaxation time (150/150 ms), fascinating recoverability, excellent response stability within a wide workable detection range up to 80% strain (corresponding pressure of 584.4 kPa) and a superior durability (>10000 cycles), which is mainly related to the pinnate-veined aligned porous structure along the orientation direction. The CTF was then assembled as a wearable sensor to monitor various human motions such as arm bending, squatting, tiptoeing, etc., showing good detection performances. The sensor can also deal with water pollution through oil/water separation, suggesting its multifunctionality and promising prospects in complicated situations. [ABSTRACT FROM AUTHOR]

Simultaneously Enhanced Efficiency and Mechanical Durability in Ternary Solar Cells Enabled by Low-Cost Incompletely Separated Fullerenes Tech-PCBM slightly disrupts the crystallization of polymers, and disperses well into the amorphous polymer regions of the all-PSC blends, thus facilitating charge transport and improving film ductility simultaneously. B Front Cover b : Article 2200139 by Yuanyuan Kan, Ke Gao and co-workers shows that both improved mechanical durability and efficiency are achieved in the all-PSCs with low-cost incompletely separated fullerenes. [Extracted from the article]

Abstract: In the paper, Si element was added in Mg–15Al alloy and processed by the equal channel angular processing (ECAP) for 4 passes using route Bc at 300°C. Microstructure characteristics of experimental alloys before and after ECAP were observed by OM, SEM, EDS and XRD. Tensile test (25, 150 and 200°C) was carried out by a WDW-100KN tensile testing machine. The results show that the grain size of as-cast Mg–15Al alloy was decreased with addition of 1wt% Si element, and new Mg2Si phase formed in the matrix. Meanwhile, network β-Mg17Al12 phases tend to form with the increasing amount of β. After processing by ECAP, the net structure of β-Mg17Al12 phases was disappeared and the morphology was modified. Moreover, the grain size of α-Mg matrix was decreased sharply, from 11.3μm (in Mg–15Al) to 5.98μm (in Mg–15Al–1Si), and Coarse Chinese script Mg2Si phase emerged in Mg–15Al–1Si alloy was broken into particle with dimension of ~3μm by ECAP simultaneously. As a result, the mechanical properties of Mg–15Al–1Si and Mg–15Al alloy were improved by ECAP and the increased amount of Mg–15Al–1Si alloy was greater than that of Mg–15Al, about 51.6MPa in room temperature tensile strength. The Mg2Si phases with high melting were fragmented by ECAP and distributed uniformly in matrix, thus, the mechanical properties of ECAPed Mg–15Al–1Si alloy were more excellent at high temperature, comparing with other experimental alloys. [Copyright &y& Elsevier]

The preparation of a satisfactory strain sensor integrated with ultrahigh sensitivity, large application range and superior stability is still a huge challenge. Herein, a highly stretchable carbon black/thermoplastic polyurethane fibrous strain sensor with porous and core-sheath structure is successfully prepared via an efficient coaxial wet-spun approach. The fiber possesses a porous monolith structure owing to countercurrent diffusion of the solvent and coagulation. An ultrahigh sensitivity (maximum gauge factor of 28,084), fast response time (200 ms), favorable durability (>11,000 cycles) and large strain range (>200%) are achieved simultaneously. Intriguingly, the values of ln (R/R 0) of the fiber show a good linearity versus tensile strain, which can be used to predict changes of sensitivity in application. The tunneling theory is employed to analyze the response behaviors. The fibrous strain sensor is then utilized for detecting various human movements and tactile sensing, proving its tremendous potential as wearable electronics. Image 1 [ABSTRACT FROM AUTHOR]