Robust multi‐walled carbon nanotubes@thermoplastic polyurethane porous films with conductive fabrics for wearable triboelectric nanogenerators

Abstract

For sustainable wearable applications, triboelectric nanogenerators (TENGs) should have the features of flexibility, robustness, biocompatibility, and integration. For this purpose, flexible TENGs were proposed using thermoplastic polyurethane (TPU) film with a porous structure and multi‐walled carbon nanotubes (MWCNT) was incorporated to enhance the output performance by forming microcapatitors. The conductive fabric was embedded in the friction layer as electrodes, convenient for integration and wearing. Benefiting from the porous structure and microcapatitor effect, the results showed that the output voltage and current of TENG based on the MWCNT@TPU porous composite film increased to 41 V, and 12.4 μA when the concentration of TPU was 18 wt% and the concentration of MWCNT was 0.3 wt%, from the original 9 V and 1.5 μA for TENG with dense TPU film. The harvested electric energy was enough to light up 148 LEDs or 18 COBs, as well as charging capacitors for powering micro‐electronics. In addition, the TENG could be used for sensing emergency situations and identifying objects. Generally, the designed TENG provides new insights into investigating porous materials with flexibility for high performance energy harvesters.Highlights A wearable, integratable and durable triboelectric layer was developed. The triboelectric layer was optimized by incorporating carbon nanotubes. The outputs of TENG were improved by porous structure and microcapatitor effect. The TENG had a great potential in energy harvesting and protective alarm system.

Strain sensor based on polyurethane/carbon nanotube elastic conductive spiral yarn with high strain range and sensitivity

“…The substrate is usually made of elastic polymer materials such as silicone rubber, 18,19 natural rubber, 20 polyurethane, 21,22 or combinations thereof. As an important component determining the performance of strain sensors, the conductive filler is typically a metal (such as silver nanowires, 23 gold nanowires, 24 and a liquid metal 25 ) or a carbon material (such as carbon black, 26 carbon nanotubes, 27,28 or graphene 29 ). For example, Chen et al 30 using polyurethane fiber as a core layer, poly(methyl methacrylate) as an intermediate bonding layer, and gallium‐indium liquid metal as an outer conductive layer, developed a three‐layer conductive fiber with excellent electrical properties (>103 S/cm) and a stretching range of over 500%, which could be used for human motion monitoring.…”