RESUMEN

Triboelectric nanogenerator (TENG) has the great potential to harvest the electrostatic energy and mechanical energy of raindrops. However, raindrops are small and scattered, and it is difficult to harvest their mechanical energy effectively. In this paper, a gridding triboelectric nanogenerator (G-TENG) with an area of 81 cm2 is designed and developed to effectively harvest the mechanical energy of raindrops on a large scale. Its peak output power density is 8.56 mW/m2, which is 245 times the value of 35 µW/m2 of a general TENG without gridding. Each unit of the G-TENG can work independently, which can effectively decrease the mutual counteraction of elastic deformation among the adjacent positions of the raindrop impacting layer and avoid the accumulation of raindrops. Under the impact of simulated raindrops from a shower at a flow rate of 0.137 mL/(cm2·s), the open-circuit voltage (Voc) and the short-circuit current density (Jsc) of the G-TENG reach 400 V and 2.5 mA/m2, respectively. The peak output power density reaches 110 mW/m2, which is 42 times the reported maximum value of 2.6 mW/m2 of raindrop energy harvesting TENGs with the size larger than 10 cm2. Moreover, the G-TENG can harvest the mechanical energy of raindrops at a wide range of raindrop flow rates from 0.055 to 0.219 mL/(cm2·s). This work contributes to the raindrop mechanical energy harvesting on a large scale.

RESUMEN

Fiber-based nanogenerators have great potential applications in wearable electronics such as portable nanodevices, e-skin, and artificial intelligence system. Here, we report a kind of fiber-based electret nanogenerator (FENG) with a semisupported core-shell structure. Owing to its unique structure, the open-circuit voltage and short-circuit current of the FENG reach 40 V and 0.6 µA, respectively, under a short working distance (∼25 µm). No obvious degradation of the output performance under a long-time continuous work (>16 h) and different humidity environments (20-95%) is observed, which demonstrates the FENG's good reliability and stability. Many universal materials, such as cotton rope, conductive sewing thread, and polyvinyl chloride tube, have been successfully used to fabricate FENG. Meanwhile, the FENG-based wearable fabric has been successfully developed to effectively harvest mechanical energy of human motion. The FENG is highly effective, reliable, and stable, promoting the development of fiber-based nanogenerators and their applications in self-powered wearable electronics.

Asunto(s)

Suministros de Energía Eléctrica , Dispositivos Electrónicos Vestibles , Cobre/química , Dimetilpolisiloxanos/química , Electrodos , Humanos , Movimiento , Politetrafluoroetileno/química , Plata/química , Textiles

RESUMEN

Usually, high temperature decreases the output performance of triboelectric nanogenerator because of the dissipation of triboelectric charges through the thermionic emission. Here, a temperature difference triboelectric nanogenerator is designed and fabricated to enhance the electrical output performance in high temperature environment. As the hotter friction layer's temperature of nanogenerator is 0 K to 145 K higher than the cooler part's temperature, the output voltage, current, surface charge density and output power are increased 2.7, 2.2, 3.0 and 2.9 times, respectively (from 315 V, 9.1 µA, 19.6 µC m-2, 69 µW to 858 V, 20 µA, 58.8 µC m-2, 206.7 µW). With the further increase of temperature difference from 145 K to 219 K, the surface charge density and output performance gradually decrease. At the optimal temperature difference (145 K), the largest output current density is 443 µA cm-2, which is 26.6% larger than the reported record value (350 µA cm-2).