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Accurate and continuous detection of physiological signals without the need for an external power supply is a key technology for realizing wearable electronics as next‐generation biomedical devices. Herein, it is shown that a MXene/black phosphorus (BP)‐based self‐powered smart sensor system can be designed by integrating a flexible pressure sensor with direct‐laser‐writing micro‐supercapacitors and solar cells. Using a layer‐by‐layer (LbL) self‐assembly process to form a periodic interleaving MXene/BP lamellar structure results in a high energy‐storage capacity in a direct‐laser‐writing micro‐supercapacitor to drive the operation of sensors and compensate the intermittency of light illumination. Meanwhile, with MXene/BP as the sensitive layer in a flexible pressure sensor, the pressure sensitivity of the device can be improved to 77.61 kPa–1 at an optimized elastic modulus of 0.45 MPa. Furthermore, the smart sensor system with fast response time (10.9 ms) shows a real‐time detection capability for the state of the human heart under physiological conditions. It is believed that the proposed study based on the design and integration of MXene materials will provide a general platform for next‐generation self‐powered electronics.

MXenes are an emerging class of 2D transition metal carbides and nitrides. They have been widely used in flexible electronics owing to their excellent conductivity, mechanical flexibility, and water dispersibility. In this study, the electrode and active layer applications of MXene materials in electronic skins are realized. By utilizing vacuum filtration technology, few‐layer MXene electrodes are integrated onto the top and bottom surfaces of the 3D polyacrylonitrile (PAN) network to form a stable electronic skin. The fabricated flexible device with Ti3C2Tx MXene electrodes outperforms those with other electrodes and exhibits excellent device performance, with a high sensitivity of 104.0 kPa−1, fast response/recovery time of 30/20 ms, and a low detection limit of 1.5 Pa. Furthermore, the electrode and the constructed MXene/PAN‐based flexible pressure sensor exhibit robust mechanical stability and can survive 240 bending cycles. Such a robust, flexible device can be enlarged or folded like a jigsaw puzzle or origami and transformed from 2D to 3D structures; moreover, it can detect tiny movements of human muscles, such as movements corresponding to sound production and intense movements during bending of fingers.

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The existence of rechargeable lithium ion batteries with high operating voltage, high energy density, and excellent cycling performance are drawing increasing attention due to their viability to be used as portable power and in electrical applications. However, there is a considerable problem that the conductivity of the active material becomes poor due to the volume expansion under the condition of repeated circulation, which reduces the performance of the device, thus hindering its practical application. As an emerging 2D material, black phosphorus (BP) has drawn significant attention in the field of Li‐ion battery energy storage due to its large theoretical capacity of 2596 mA h g−1 and ability to absorb large amount of Li atoms. Here, a unique 3D conductive structure with the BP and carbon nanotubes (CNTs), displaying good stability and high conductivity for the fabrication of BP@CNTs hybrid‐based Li‐ion batteries is described. With strong trapping, good affinity, structure stable, and high adsorption for polyphosphorus, the developed BP@CNTs hybrid electrodes display high capacity, good electrical conductivity, and a stable cycle life. Additionally, the lithium ion batteries can illuminate the light emitting diode, proving that the materials have great potential for development of energy storage devices.

Ionic liquid was used as microwave absorption medium and applied to the extraction of essential oils from dried fruits of the Illicium verum Hook. f. and Cuminum cyminum L. by microwave-assisted extraction. The extraction time is less than 15 min at the microwave power of 440 W. The constituents of essential oils obtained by the proposed method were compared with those obtained by hydrodistillation. There is no obvious difference in the constituents of essential oils obtained by the two methods.

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