No abstract

Flexible and interlaced-designed triboelectric nanogenerators (TENGs) are acquiring enormous research interest due to their facile fabrication techniques and easy employment as a power source for wearable/portable electronic devices. Herein, we proposed polypyrrole (PPy)-based flexible and wearable TENGs with excellent electrical output performance and robustness. The flexible interlaced microfibrous mesh cotton fabric was used as a support frame to deposit PPy by an in situ chemical polymerization process. Such PPy-coated cotton textile (PPy@CT) was utilized as an electrode to construct a single-electrode-mode TENG. Furthermore, a sandpaper-assisted microtextured polydimethylsiloxane layer was developed on the top of PPy@CT via a simple softimprint lithography technique, and it was employed as a tribonegative friction layer of TENG. The resultant PPy-based wearable single-electrode-mode TENG (PPy-WSEM-TENG) device can efficiently convert the mechanical energy into electricity while making continuous contacts/separations with counter friction objects like dialysis cellulose membrane and human skin (i.e., tribo-positive friction layers). Moreover, the influence of an external pressing force and load resistance on the electrical output performance of PPy-WSEM-TENG was analyzed. This device exhibited robust characteristics even after long-term cyclic operations and also generated an electrical output by gently touching with the human hand. For commercial applications, the asfabricated PPy-WSEM-TENG was effectively employed as a self-powered source to drive portable electronic devices as well as light-emitting diodes.

Triboelectric nanogenerators (TENGs) are gaining much research interest recently owing to their facile and cost-effective device structure. However, the effect of relative humidity (in moisture atmosphere) on the output performance still needs to be resolved. Herein, a pouch-type TENG is proposed to significantly reduce the effect of relative humidity on its electrical output and a stable performance is also attained in a humid environment. In this regard, a dielectric and dielectric materials-based TENG (DD-TENG) is first developed using nanoarchitecture polydimethylsiloxane (NA-PDMS) and multiwalled carbon nanotube/nylon composite layers as a triboelectric material with the negative and positive tendencies, respectively. The NA-PDMS and nylon composite layers play a key role in increasing the surface contact area and surface charge density between the dielectric/triboelectric materials as well as the output performance of DD-TENG. However, the DD-TENG device exhibits a stable and high output performance with the effective output power density of ≈25.35 W m −2 . Additionally, the performance of the pouch-type DD-TENG device is not almost affected even though the relative humidity is increased from 35 to 81%, while it is dramatically decreased for the nonpouchtype device. Finally, the pouch-type DD-TENG is employed as a wearable device to effectively harvest the mechanical energy from daily human activities.

No abstract

A composite film consisting of Al-doped BaTiO3 particles with high ferroelectricity is used to enhance the output performance of nanogenerators.