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Flexible photoelectrochemical (PEC) based sensors have been extensively investigated for noninvasive healthcare monitoring. However, known electrode materials struggle to combine technologically relevant metrics of high sensitivity and flexibility due to their low electrical conductivity and fragile mechanical properties. Herein, a flexible PEC‐based sensor for dopamine (DA) detection is presented by integrating highly conductive and flexible MXene between CdS quantum dots and g‐C3N4 with suitable energy level matching. Theoretical calculations reveal that the interfaces of constructed PEC electrodes with enhanced electronic conductivity derived from MXene not only improve the electron transfer kinetics, but form built‐in electric fields at the interfaces, facilitating the separation efficiency of electron–hole pairs. As a result, the as‐prepared sensors display the combined advantages of a wide detection range (1 nM–0.1 mM), low detection limit (0.48 nM), high stability, selectivity, and repeatability for DA detection. Building on these metrics, a scalable screen‐printing method is further developed for integrating the sensors on flexible platforms. These all‐integrated PEC‐based sensors exhibit stable photocurrent signals under different bending angles and bending cycles. Therefore, this work demonstrates the scalable development of flexible PEC‐based sensors for the sensitive detection of DA and holds promise for the future development of noninvasive healthcare monitoring. [ABSTRACT FROM AUTHOR]

Scalable assembly of two dimensional (2D) lamellar nanomaterials for deformable films has potential in wearable energy storage devices, but overcoming the trade‐off in mechanical and energy storage properties is a challenge. Here, a blade‐coating strategy is reported to develop highly stretchable and bendable metal‐organic frameworks/large‐sized Ti3C2Tx MXene (MOF/LMX) composite films on the pre‐stretched elastomer substrates. The LMX sheets serve as conductive scaffolds for loading the small‐sized ultrathin MOF sheets (SUMOFs), resulting in an improved tensile strength (≈97 MPa) of the films, which guarantees their structural integrity when forming a wavy structure on a relaxed substrate. In addition, SUMOFs incorporated in‐between LMX layers not only expose active redox sites by mitigating the intrinsic self‐restacking of MOF but also accelerate the electron transfer in the redox reaction process revealed through the density functional theory calculations. As a result, the composite films deliver high electrical conductivity (3244 S cm−1) and energy storage capability (1238 F g−1). When assembled into an asymmetric supercapacitor device, it also exhibits stable performances under different bending and stretching states. Thus, the development of conducting and deformable MOF‐based films with high mechanical, electrical, and energy storage properties enables their potential commercial applications for wearable electronics. [ABSTRACT FROM AUTHOR]

Developing solar‐driven desalination through interfacial steam generation is crucial to reducing global water shortages. However, traditional solar steam generation systems have faced efficiency, durability, cost, and complexity limitations. To overcome these issues, interfacial solar steam evaporators are fabricated using light‐absorbing materials with low thermal conductivity, high absorption capacity, and sufficient mechanical strength. Herein, an advanced 3D solar evaporator is developed by coating MXene onto the surface of the aramid nanofiber aerogels (MX@ANF aerogels). The MXene coating enhances the ANF aerogels' light absorption and thermal conversion capabilities. Additionally, the hydrophilicity of MXene complements the high porosity of the host aerogels, enhancing continuous water supply by improving the capillary action. Primarily, these MX@ANF aerogels show promising performance at the air–water interface, with an evaporation rate of 1.48 kg m−2 h−1 and steam conversion efficiency of 93.8% under 1 sun irradiation (1 kW m−2). These highlight the effectiveness of the MX@ANF aerogel as a material for solar‐driven desalination. Moreover, using MXene as a photothermal agent in composite materials paves new avenues toward efficient and cost‐effective solutions for addressing water scarcity through solar desalination. [ABSTRACT FROM AUTHOR]

In response to the problems of complex background in the aerial images of the UAV which brings about seriously missed detection as well as poor detection precision, and excessive parameters as well as slow detection speed in the present deep network, an object detection algorithm of UAV vehicle based on Eficientnet is proposed. Firstly, Eficientnet, the lightweight network, is introduced as the feature extraction network of the YOLOv3 model, reducing the size of the model parameters and improving the detection speed of the algorithm. Secondly, the UAV vehicle dataset is clustered by the K-means algorithm to obtain the better bounding box size, thus improving the detection precision. Finally, with the CIoU bounding box loss function, the regression loss of the model is improved, thus enhancing the convergence ability of the model. Experimental results show that mAP of 92.60% and FPS of 31.15 can be achieved in the self-made UAV vehicle dataset based on the improved algorithm, which is 2.12 percentage points and 9.87 higher than the original algorithm, respectively. Therefore, it is more suitable for vehicle detection tasks in UAV scenarios. [ABSTRACT FROM AUTHOR]

Ti3C2Tx MXene thin-film electrodes are promising for flexible and wearable energy storage devices. Meanwhile, the restacking of MXene nanosheets largely affects their electrochemical properties when processing them into freestanding films. Introducing interlayer spacers can effectively eliminate this restacking problem; however balancing the restacking and mechanical strength of these films remains challenging. Here, an efficient strategy that utilizes ice crystals to help intercalate aniline monomers into a pre-frozen hydro-MXene film, followed by an in situ polymerization, is proposed. The ice crystals grown within the hydro-film significantly enlarge the interlayer space, facilitating the intercalation of aniline monomers dispersed into the MXene film. By minimizing the polyaniline (PANI) loading (0.6 wt%), the resultant PANI/MXene film shows both high mechanical strength (∼47 MPa) and electrochemical performances including a high volumetric capacitance of 1360 F cm−3 (gravimetric capacitance of 385 F g−1), rate performance (53.5% even at an ultrahigh scan rate of 10 V s−1) and stable cycling stability with 96.4% capacitance retention after 10 000 cycles. Moreover, the assembled supercapacitor device demonstrates good structural stability and flexibility under different bending tests. Thus, this work provides an efficient approach for fabricating MXene based thin films with a good balance of mechanical strength and electrochemical performances. [ABSTRACT FROM AUTHOR]

Herein, the fabrication of reduced graphene oxide (RGO)‐templated polymer composites for chemical removal of gaseous formaldehyde under ambient conditions is presented. The chemical removal of formaldehyde is achieved by a nucleophilic addition reaction between formaldehyde and aminooxy groups on the polymer chain ends to form the oxime bonds with the only byproduct of H2O. RGO is essential since it not only has an ultralarge surface area but also can act as a perfect template for immobilizing pyrene‐terminated and aminooxy‐functionalized polymers via strong π–π stacking interactions, while melamine foam provides a three‐dimensional skeleton for loading RGO/polymer composites to afford a porous 3D structure for efficient formaldehyde removal. Since the oxime bond can be cleaved into aminooxy group in acidic media, the RGO/polymer composite can be regenerated for repeatable usage, which shows an excellent performance of adsorbing 14 mg of formaldehyde by 100 mg of the polymer at ambient condition. [ABSTRACT FROM AUTHOR]