Compared with thin‐film morphology, 1D perovskite structures such as micro/nanowires with fewer grain boundaries and lower defect density are very suitable for high‐performance photodetectors with higher stability. Although the stability of perovskite microwire‐based photodetectors has been substantially enhanced in comparison with that of photodetectors based on thin‐film morphology, practical applications require further improvements to the stability before implementation. In this study, a template‐assisted method is developed to prepare methylammonium lead bromide (MAPbBr3) micro/nanowire structures, which are encapsulated in situ by a protective hydrophobic molecular layer. The combination of the protective layer, high crystalline quality, and highly ordered microstructures significantly improve the stability of the MAPbBr3 single‐crystal microwire arrays. Consequently, these MAPbBr3 single‐crystal microwire‐array‐based photodetectors exhibit significant long‐term stability, maintaining 96% of the initial photocurrent after 1 year without further encapsulation. The lifetime of such photodetectors is hence approximately four times longer than that of the most stable previously reported perovskite micro/nanowire‐based photodetector; this is thought to be the most stable perovskite photodetector reported thus far. Furthermore, this work should contribute further toward the realization of perovskite 1D structures with long‐term stability.

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drug delivery, [18,19] matrices for bioseparations, etc. [20,21] In recent years, hydrogel actuator, as new type device, receives extensive attention due to distinct advantages: mimic human functionality, adaption in aqueous environments, simple designs, and potential applications in various fields, including biology, [22] medicine, [23,24] microfluidics, [25,26] and robotics. [27] Among the stimuli-responsive actuators, light-driven actuators are particularly attractive devices. Light enables the rapid on-off switching and higher spatial and temporal resolution than other stimuli. Furthermore, light as a stimulus enables facile operation with removing complex step of installing wire. Until now, two main strategies have been developed for fabrication of actuators with light stimulation. As one strategy, photoirradiation-induced ionization/isomerization of chromophores enables the majority of light-driven actuators, in which the size change of azobenzene, [28][29][30][31] spiropyran, [32,33] diarylethene, [34] and so forth [35] leads to motions of the actuators. However, these cited instances of ionization/isomerization reaction were limited by slow actuation kinetics, no significant deformation, or narrow selection of efficient spectral range.Another important strategy is introducing photothermal nanoparticles into thermoresponsive matrices, which undergo a reversible and significant volume change exceed certain temperature. Hauser et al. demonstrated transformations from a single flat gel sheet to buckled shapes due to local photothermal shrinking under light irradiation. [36] In addition, light-induced poly(N-isopropylacrylamide) (PNIPAm) bilayer hydrogel actuators have been widely reported. In the study of Zhang et al., graphene oxide-poly(N-isopropylacrylamide) (PNIPAm) nanocomposite and PNIPAm nanocomposite bilayer gels change the isotropic volume contraction into a simple bending deformation. [37] In the study of Zhou et al., they generated a simple holistic movement. [38] Up to now, light-driven actuator can achieve wireless remote control operation using photothermal transformation agent, but a local operation and flexible shape change still absent. Here we fabricated gold nanoparticles (AuNPs)-doped PNIPAm light-driven actuators that could rapidly undergo arbitrary, flexible, and fully programmable of Hydrogel actuators represent a powerful tool due to their ability to capture, move, and be manipulated, which has applications in diverse fields. The development of hydrogel actuators capable of localized movement, where only a part of the whole system moves, wireless remote control, and flexible shape-changing is critical and challenging to fulfill their potential. Here, photothermal hydrogel actuators are designed and fabricated to accomplish a precise hand-like manipulation of encapsulating and finger-like one-by-one bending by light. A thermoresponsive poly(N-isopropylacrylamide) (PNIPAm) active layer and a non-thermoresponsive poly(acrylamide) passive layer are combined to generate a thermal-expansion ...

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Highly ordered 2D layered perovskite micro-wire arrays were fabricated by the template-confined growth method. Based on this, a high-performance, stable and polarization-sensitive photodetector was achieved.

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Gold nanoparticles were assembled into highly aligned micro/nanowires for flexible pressure sensors.

Paper-based photodetectors have attracted extensive research interest owing to their environmentally friendly and highly deformable properties. Although perovskite crystals with outstanding optoelectronic properties have proved to be one of the most promising candidates for photodetectors, the development of paper-based photodetectors is hindered by the moisture absorptivity of paper and the instability of perovskite crystals in a humid atmosphere. In this study, we demonstrate a highly deformable and high-performance paper-based perovskite photodetector. The photodetector maintains its excellent performance even after exposure to a relative humidity of 60% for 120 h.