Electrospinning Machine| Multifunctional Sensitive Positive Friction Layer ofTPU/MXene/STo Composited Film for TriboelectricNanogenerator

Triboelectric nanogenerators (TENGs) are ideal candidates for flexible wearable electronics due to their simple structure, high output voltage, and high sensitivity. However, current flexible TENGs still face bottlenecks in insufficient output performance for wearable applications.

To address this, Associate Professor Zhang Yanhu, Dr. Gao Mang, and Associate Professor Liu Bao from Jiangsu University prepared a positive triboelectric layer with fillers via electrospinning technology, featuring a dense and irregular surface structure to enhance output performance. By adjusting the composite filler ratio of conductive MXene nanosheets and ferroelectric strontium titanate (STO) nanoparticles, their impact on output performance was studied. Compared to pure thermoplastic polyurethane (TPU), the TENG based on TMS (TPU/MXene/STO) exhibited 7-fold higher voltage and 34-fold higher current. Additionally, the fabricated TENG was successfully applied to flexible sensing, capable of detecting curvature from gripping different objects and various breathing conditions, demonstrating broad prospects for smart sensing and health monitoring. This study developed a low-cost, high-performance, and highly sensitive TENG with significant potential for smart wearable devices. The research, titled "Multifunctional Sensitive PoFig. 2. (a) SEM images and fiber diameter distribution of electrospun fibers with varying STO content. (b) XRD patterns of TPU, STO, and TPU/STO composite films. (c) Stress-strain curves of composite films. Overall trends of open-circuit voltage (d) and short-circuit current (e) for TPU/STO.sitive Friction Layer of TPU/MXene/STO Composited Film for Triboelectric Nanogenerator," was published in Nano Letters.

Fig. 1. (a) Preparation process of the positive triboelectric layer. (b) Structure and working principle of a contact-separation TENG. (c) Simulated potential distribution during contact and separation.

Fig. 2. (a) SEM images and fiber diameter distribution of electrospun fibers with varying STO content. (b) XRD patterns of TPU, STO, and TPU/STO composite films. (c) Stress-strain curves of composite films. Overall trends of open-circuit voltage (d) and short-circuit current (e) for TPU/STO.

Fig. 3. (a) EDS mapping of MXene composite electrospun films. (b) Multi-cycle open-circuit voltage and (c) short-circuit current of TENGs with varying MXene content. Overall trends of open-circuit voltage (d) and short-circuit current (e) for TPU/MXene.

Fig. 4. (a) XRD patterns of TPU/MXene/STO composite films, STO, and MXene nanosheets. (b) EDS spectrum of TPU/MXene/STO fibers. Overall trends of open-circuit voltage (c) and short-circuit current (d) for TPU/MXene/STO. (e) Charge distribution and working mechanism of the TMS triboelectric layer.

Fig. 5. (a) TENG attached to a finger for monitoring electrical signals at different bending angles. (b) Signal trends during finger bending. (c) Conversion of motions (gripping tape, holding a cylinder, or clenching) into electrical signals for hand-motion recognition. (d) Current output signals of TMS-based TENG for identifying airflow under different breathing patterns.

This work was supported by the National Natural Science Foundation of China (51705210), the Open Fund of the State Key Laboratory of Mechanical System and Vibration (No. MSV202516), and the Jiangsu Postdoctoral Research Funding Program (2019K195).Associate Professor Zhang Yanhu from Jiangsu University is the first author and corresponding author. Collaborators include Jiangsu University master students Gu Jiawei and Shi Zhan, Professor Wu Jiang from Shandong University, Associate Professors Li Jianwei, Fu Hao, and Ji Jinghu from Jiangsu University, and Associate Researcher Yang Bingjun from the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences. Dr. Gao Mang from Central South University and Associate Professor Liu Bao from Jiangsu University are co-corresponding authors.

Original Link: https://pubs.acs.org/doi/10.1021/acs.nanolett.5c00048