Structured piezoresistive membranes are compelling building blocks for wearable bioelectronics. However, the poor structural compressibility of conventional microstructures leads to rapid saturation of detection range and low sensitivity of piezoresistive devices, limiting their commercial applications. Herein, a bioinspired MXene-based piezoresistive device is reported, which can effectively boost the sensitivity while broadening the response range by architecting intermittent villus-like microstructures. Benefitting from the two-stage amplification effect of this intermittent architecture, the developed MXene-based piezoresistive bioelectronics exhibit a high sensitivity of 461 kPa −1 and a broad pressure detection range of up to 311 kPa, which are about 20 and 5 times higher than that of the homogeneous microstructures, respectively. Cooperating with the deep-learning algorithm, the designed bioelectronics can effectively capture complex human movements and precisely identify human motion with a high recognition accuracy of 99%. Evidently, this intermittent architecture of biomimetic strategy may pave a promising avenue to overcome the limitation of rapid saturation and low sensitivity in piezoresistive bioelectronics, and provide a general way to promote its largescale applications.

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The interfacial effect is widely used to optimize the properties of ferroelectric nanocomposites, however, there is still a lack of direct evidence to understand its underlying mechanisms limited by the nano size and complex structures. Here, taking piezoelectricity, for example, the mechanism of interfacial polarization in barium titanate/poly(vinylidene fluoride‐ran‐trifluoroethylene) (BTO/P(VDF‐TrFE)) nanocomposite is revealed at multiple scales by combining Kelvin probe force microscope (KPFM) with theoretical stimulation. The results prove that the mismatch of permittivity between matrix and filler leads to the accumulation of charges, which in turn induces local polarization in the interfacial region, and thus can promote piezoelectricity independently. Furthermore, the strategy of interfacial polarization to enhance piezoelectricity is extended and validated in other two similar nanocomposites. This work uncovers the mechanism of interfacial polarization and paves newfangled insights to boost performances in ferroelectric nanocomposites.

Electrospun piezoelectric membranes are compelling building blocks for constructing wearable bioelectronics. However, the efficiency of electromechanical conversion over a wide bandwidth is still insufficient due to the restriction between fiber dipole alignment and energy absorption. Topology optimization is a mathematical method that lets us optimize the layout of a system to maximize its performance given a set of boundary conditions and constraints. Here, topological designs as a reinforcement mechanism are developed to enhance the electromechanical response of electrospun piezoelectric membranes. The topologically optimized membranes show a 300% increase in electric output and a 478% increase in frequency response range compared with traditional electrospun membranes. With the optimized piezoelectric membrane design, the developed textile acoustic sensors can capture the human voice for speech recognition with a classification accuracy of up to 100% with the help of deep learning. Because of the universality and superiority of this new topologically optimal design, it represents a milestone in designing electrospun membranes for electromechanical conversion and high‐performance soft bioelectronics.

MXenes have received tremendous attention for flexible electronics owing to their excellent conductivity, water dispersibility, and mechanical flexibility. However, the sediment from the MXene production process is usually discarded as trash, resulting in low utilization. Here, we present a flexible pressure sensor that enables micro-force sensing and efficient utilization of MXene by confining MXene trash among structured MXene electrodes. Benefiting from the synergistic effect of both the confined micro-conical structure and easily changeable space of MXene trash, the as-designed device can detect extremely subtle pressure of 2.9 Pa, deliver a high sensitivity over 4.08 kPa −1 , and exhibit a remarkably fast response time (7 ms). These properties make it suitable for monitoring weak force signals from human wrist pulse and even for detecting dynamic responses associated with acoustic waves. This work provides a reference for the versatile and efficient application of MXene in the same device, showing great potential for sustainable production of next-generation wearable smart electronics.