With the rapid development of wearable electronics, flexible and sensitive energy harvesters have recently attracted considerable attention. Herein, a novel piezo-triboelectric nanogenerator (PTNG) based on BCZT/PVDF-HFP composite nanofibers (BP-based NFs) is fabricated using silicone rubber as the negative triboelectric counterpart. The introduction of BCZT nanoparticles markedly improves both the piezoelectric and triboelectric properties of the BP-SG PTNG, where the output voltage and current density are 2.5–3 fold higher than those of pure PVDF-HFP PTNG. Owing to the uniform distribution of BCZT particles on the fiber surface via electrospinning, the maximum power density of the device reaches 161.7 mW m⁻², representing 5.5-fold improvement compared to that of BaTiO₃/PVDF-based composite PTNG. The device shows stable output for 1200 cycles and after three month storage and exhibits high sensitivity to minute body movements as proved by the output response in both two-electrode and single-electrode modes. This study demonstrates a novel approach to fabricate flexible PTNGs with simple structure and high sensitivity for use in self-powered wearable electronics.

This study investigates the electrochemical performance of polycrystalline and single-crystal NCM811 materials. Our findings show that the polycrystalline sample has a higher discharge capacity and better C-rate performance than the single-crystal sample, while single crystal materials exhibit better capacity retention and cycling stability. We also find that crystal structure defects caused by Li/Ni mixing play an important role in structural stability during electrochemical cycling. In contrast to previous studies, we argue that the stability of single crystals is not only due to the less generation of microcracks but also due to their near-perfect Rm crystal layer structure. Additionally, we find that lattice disorder resulting from crystal fusion rearranges during the transition from polycrystalline to single crystal morphology can significantly affect the release of electrochemical properties of the material. Our study suggests that reducing crystal structure defects in polycrystalline materials and improving lithium ion diffusion in single crystal materials can enhance their electrochemical performance. Our study provides valuable insights into the relationship between crystal morphology and electrochemical performance, which can guide the design and synthesis of high-performance cathode materials for lithium-ion batteries.