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Microfluidics and bioinspired superwetting materials, as two crucial branches of scientific research, are entering their golden age of development. As an emerging interdisciplinary subject of these two fields, bioinspired superwetting open microfluidics is triggering technological revolutions in many disciplines, including rapid medical diagnosis, biochemical analysis, liquid manipulation, 3D printing, etc. However, this new research area has yet to attract extensive attention. So, a timely review is necessary to organize the development process, summarize current achievements, and discuss the challenges or chances for the ongoing scientific trend. In this review, the evolution from closed to open microfluidics is combed first. Then, three typical bioinspired superwetting systems are introduced emphatically. Based on this, the bioinspired superwetting open microfluidics is divided into different categories according to the bionic objects as the focus of this study. Taking natural phenomena as the entry point, the research from the underlying mechanism to the application is systematically discussed and summarized. Several emerging applications are also mentioned. Finally, some views on major problems, existing challenges, and developing trends are briefly put forward in this field to guide future research. [ABSTRACT FROM AUTHOR]

Microfluidics has experienced rapid progress in additive manufacturing and microfluidic soft robots. The design of microfluidics is already moving into a more intelligent, integrated, and detachable direction. However, the pipeline resistance needs more external energy input to achieve high flow speed. Guided transport of liquid in the open‐air‐space microfluidics will be an effective solution. Inspired by the water shuttle on the pitcher plant tendril, herein, an open‐air microfluidic transport device is designed that consists of a superhydrophilic microwick with multi‐microgrooves by stereolithography. The liquid film confined in microgrooves can promote rapid fluid shuttle on the wet surface to enhance transport rate and inhibit the Rayleigh‐Plateau instability from forming larger dripping drops. The dripping volume and threshold Capillary number are optimized for effective liquid transport and drainage. State‐of‐the‐art microwick liquid shuttle technologies can guide liquid continuously in a prescribed direction or into multiple directions with 98% transport efficiency (the ratio of liquid collection volume and liquid injection volume) for water and 97% for ethanol in the closed‐open‐closed space. The proposed mechanism has the potential to streamline microfluidic applications—and, therefore, accelerate relevant liquid delivery development and ultimately their applications in microfluidic chip and additive manufacturing. [ABSTRACT FROM AUTHOR]

Highly sensitive flexible pressure sensors are extensively investigated for various applications, such as electronic skin, human physiological monitoring, and artificial intelligence. However, traditional fabrication technologies are hard to realize the large‐area and mass production of wearable sensing devices. Current trend of miniaturization, systematization, and multifunction has raised the problems of total energy consumption, frequent charging, and reduced usage time. These issues have hindered the progress of wearable sensing electronics. In the light of nanomaterial design, mass production, and facile manufacturing, electrospun piezoelectric pressure sensors offer the best properties of self‐powering, breathability, stretchability, and flexibility, providing ideal interfacing platforms for smart wearables. Tremendous advances have been achieved recently in the high sensitivity, piezoelectric output, composite optimization, and nano‐/microstructure design of nonwoven nanofiber membranes. Nevertheless, how to fulfill real textile‐level integration in consideration of biocompatibility, integration, wearability, geometrical design, multifunction, and systematization remains a big challenge. Therefore, recent progress of piezoelectric pressure sensors from electrospun nanofibers to their fabrics is comprehensively summarized. Plentiful strategies, structure designs, and underlying mechanisms that boost the piezoelectric properties are discussed. Lastly, the challenges and possible solutions for the future electrospinning‐based pressure sensing systems are proposed. [ABSTRACT FROM AUTHOR]

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