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Highly stretchable aerogel films are attractive for advanced next‐generation stretchable electronics. However, it is a great challenge to achieve high stretchability for aerogel films. Here, several types of unprecedented ultra‐stretchable semiconducting polymer‐based aerogel films with crimpled porous structures are developed via crosslinking and template methods combined with uniaxial and biaxial pre‐stretching strategies. The semiconducting aerogel films obtained by uniaxial pre‐stretching exhibit ultrahigh stretchability up to 100–200%, while those obtained by biaxial pre‐stretching show high biaxial stretchability up to 50%. The resulting aerogel films show strain‐insensitive electrical and joule heating properties. A prototype of the aerogel film‐based stretchable organic electrochemical transistor (OECT) is developed for the first time. Benefiting from their unique porous structures, the aerogel film‐based OECTs exhibit enhanced on/off ratio and transconductance compared with corresponding dense film‐based OECTs, high stretchability up to 100%, and high stretching stability with 10 000 stretching cycles under 30% strain. It is demonstrated that the aerogel film‐based OECTs can be applied as high‐performance stretchable artificial synapses and biosensors. This work gives a versatile strategy toward highly stretchable aerogel films promising for flexible electronics. [ABSTRACT FROM AUTHOR]

Super304H steel, imbued with trace amounts of TiC/TiB2 nano-particles, was fabricated to assess the influence of nano-particles on its creep properties under the condition of 600 °C/330 MPa. Our findings elucidate that the inclusion of trace TiC/TiB2 led to a 21% improvement in the creep life of Super304H steel, while diminishing the creep rate from 6.6 × 10−5 h−1 to 5.7 × 10−5 h−1. The synergistic precipitation strengthening of the nano-scale Cu-rich phases, needle-like M23C6 phases, and NbN phases was primarily responsible for this exceptional creep resistance. During the long-term creep process, the nano-scale Cu-rich phase was very stable with little change. In the Super304H steel, M23C6 and NbN phases had a non-coherent interface and an orientation relationship of 001 NbN // 001 M 23 C 6 . M23C6 and NbN phases in the Super304H steel incorporating minute TiC/TiB2 nano-particles also had a non-coherent interface but a 1 - 10 NbN // 2 - 33 M 23 C 6 orientation relationship. The M23C6 and NbN phases effectively impede the dislocation movement and were shown to increase the creep strength considerably. [ABSTRACT FROM AUTHOR]

MXene‐based aerogels are promising candidates for wearable electronics due to their unique structures and properties. However, the reported MXene‐based aerogels show poor stretchability, significantly restricting their applications in wearable electronics. Herein, unprecedented highly stretchable MXene‐based aerogels with crimpled and reentrant microstructures are developed via synergistic assembly of MXene and flexible polymers combined with uniaxial and biaxial hot‐pressing strategies. The uniaxially hot‐pressed MXene‐based meta‐aerogels show compressed and crimpled microstructures and combine ultrahigh stretchability up to 427%, high elasticity, high compressibility, high fatigue resistance upon compression and stretching, and near‐zero Poisson's ratios. The biaxially hot‐pressed MXene‐based meta‐aerogels exhibit reentrant microstructures and achieve high stretchability and negative Poisson's ratios upon stretching in different directions, which have never been realized by traditional aerogels. It is demonstrated that they can be used for ultrabroad‐range pressure/strain sensors, highly stretchable triboelectric nanogenerators, and smart thermal management with tunable thermal insulation and Joule heating performances achieved by stretching. This work opens a new way to highly stretchable aerogels with near‐zero and negative Poisson's ratios promising in wearable electronics, nanogenerators, thermal management, energy storage, etc. [ABSTRACT FROM AUTHOR]

Neuromorphic visual system with image perception, memory, and preprocessing functions is expected to simulate basic features of the human retina. Organic optoelectronic synaptic transistors emulating biological synapses may be promising candidates for constructing neural morphological visual system. However, the sensing wavelength range of organic optoelectronic synaptic transistors usually limits their potential in artificial multispectral visual perception. Here, retina‐inspired optoelectronic synaptic transistors that present broadband responses covering ultraviolet, visible, and near‐infrared regions are demonstrated, which leverage the wide‐range photoresponsive charge trapping layer and the heterostructure formed between PbS quantum dots and organic semiconductor. Simplified neuromorphic visual arrays are developed to simulate comprehensive image perception, memory, and preprocessing functions. Benefitting from the flexibility of the charge trapping and organic semiconductor layers, a flexible neuromorphic visual array can be fabricated, having an ultralow power consumption of 0.55 fJ per event under a low operating voltage of −0.01 V. More significantly, an accelerating image preprocessing effect can be observed in a wide wavelength range even beyond the perception range of the human visual system, due to the gate‐adjustable synaptic plasticity. These devices are highly promising for implementing neuromorphic visual systems with broadband perception, increasing image processing efficiency, and promoting the development of artificial vision. [ABSTRACT FROM AUTHOR]