With the increasing demand for flexible piezoelectric sensor components, research on polyvinylidene fluoride (PVDF) based piezoelectric polymers is mounting up. However, the low dipole polarization and disordered polarization direction presented in PVDF hinder further improvement of piezoelectric properties. Here, we constructed an oriented tertiary structure, consisting of molecular chains, crystalline region, and MXene sheets, in MXene/PVDF nanocomposite via a temperature-pressure dual-field regulation method. The highly oriented PVDF molecular chains form approximately 90% of the β phase. In addition, the crystalline region structure with long-range orientation achieves out of plane polarization orientation. The parallel orientation arrangement of MXene effectively enhances the piezoelectric performances of the nanocomposite, and the current output of the device increases by nearly 23 times. This high output device is used to monitor exercise action, exploring the potential applications in wearable electronics.

Real-time monitoring of ball–shoe interactions can provide essential information for high-quality instruction in personalized soccer training, yet existing monitoring systems struggle to reflect specific forces, loci, and durations of action. Here, we design a self-powered piezoelectric sensor constructed by the gradient carbon nanotube/polyvinylidene fluoride (CNT/PVDF) composite to monitor the interactions between the ball and the shoe. Two-dimensional Raman mapping demonstrates the gradient structure of CNT/PVDF prepared by programmable electrospinning combined with a hot pressing. Benefitting from the synergistic effect of local polarization caused by the enrichment of CNT and the reduced diffusion of silver patterns in gradient structure, the as-prepared composite exhibits enhanced force-electric coupling with an excellent sensitivity of 80 mV/N and durability over 15,000 cycles. On this basis, we conformally attach a 3 × 3 sensor array to a soccer shoe, enabling real-time acquisition of kick position and contact force, which could provide quantitative assessment and personalize guidance for the training of soccer players. This self-powered piezoelectric sensor network system offers a promising paradigm for wearable monitoring under strong impact forces.

Monitoring physiological signals of the human body can provide extremely important information for sports healthcare, preventing injuries and providing efficient guidance for individual sports. However, the signals related to human healthcare involve both subtle and vigorous signals, making it difficult for a sensor to satisfy the full-scale monitoring at the same time. Here, a novel conductive elastomer featuring homogeneously micropyramid-structured PDMS/CNT composite is used to fabricate high-performance piezoresistive sensors by a drop-casting method. Benefiting from the significant increase in the contact area of microstructure during deformation, the flexible sensor presents a broad detection range (up to 185.5 kPa), fast response/recovery time (44/13 ms), ultrahigh sensitivity (242.4 kPa^–1) and excellent durability over 8,000 cycles. As a proof of concept, the as-fabricated pressure sensor can be used for body-area sports healthcare, and enable the detection of full-scale pressure distribution. Considering the fabulous sensing performance, the sensor may potentially become promising in personal sports healthcare and telemedicine monitoring.

Silicon-based anodes with high theoretical capacity have intriguing potential applications for high energy density lithium-ion batteries (LIBs), while suffer from immense volumetric change and brittle solid-state electrolyte interface that causes collapse of electrodes. Here, a stress-dissipated conductive polymer binder (polyaniline with citric acid, PC) is developed to enhance the mechanical electrochemical performance between Si nanoparticles (SiNPs) and binders. Benefiting from the stable triangle network node of citric acid and a considerable distributed of hydroxyl groups, the PC binder can effectively dissipate the stress from SiNPs, thus providing an excellent cyclic stability of Si anodes. Both experimental results and theoretical calculation demonstrate the enhanced adhesion between binders and SiNPs could bond the particles tightly to form a robust electrode. The as-fabricated Si anode exhibits outstanding structural stability upon long-term cycles that exhibit a highly reversible capability of 1021 mA·h·g⁻¹ over 500 cycles at a current density of 0.5 C (1 C = 4200 mA·g⁻¹). Evidently, this stress-dissipated binder design will provide a promising route to achieve long-life Si-based LIBs.

The development of triboelectric nanogenerator (TENG) technology which can directly convert ambient mechanical energy into electric energy may affect areas from green energy harvesting to emerging wearing electronics. And, the material of triboelectric layer is critical to the mechanical robustness and electrical output characteristics of the TENGs. Herein, a MXene enhanced electret polytetrafluoroethylene (PTFE) film with a high mechanical property and surface charge density is developed. The MXene/PTFE composite film was synthesized by spraying and annealing treatment. With the doping of MXene, the crystallinity of composite film could be tuned, leading to an enhancement in the tensile property of 450% and reducing the wear volume about 80% in the friction test. Furthermore, the as-fabricated TENG with this composite film outputs 397 V of open-circuit voltage, 21 μA of short-circuit current, and 232 nC of transfer charge quantity, which are 4, 6, and 6 times higher than that of the TENG made by pure PTFE film, respectively. Therefore, this work provides a creative strategy to simultaneously improve the mechanical property and electrical performance of the TENGs, which have great potential in improving device stability under a complex mechanical environment.