Researchers have now demonstrated a new fully flexible, wearable triboelectric nano generator (WTNG) with high power generation performance and mechanical properties.
Professor Kim, who came from the School of Advanced Materials Science and Engineering of Sungkyunkwan University, said, "We adopts a bottom-up nanostructured approach, in which we uses silver-plated textiles based on ZnO nanorod arrays and polydimethylsiloxane (PDMS) nano patterns as triboelectric materials. Nano-patterning is achieved by directly coating PDMS on vertical ZnO nanorods grown on silver-coated fabric substrate. "
Then professor Kim explained, "By increasing the effective contact area and friction force, this nano pattern heightens the triboelectrification effect, thus it produces high electrical output power, and forms a very high mechanical strength between the fabric and the nanostructure through the bottom-up nanostructure. This frictional power is generated when electric charge is formed, and this charge is much larger than the power generated by previous textile-based piezoelectric generators. And this stress may be generated by stretching or twisting textiles. When WTNG is integrated into clothing, its triboelectric properties can generate electric charge when pressed, and users may be able to power mobile electronic devices such as smart watches by moving or walking around. "
Figure 2: A Remote Control That Uses WTNG To Embed Commercial LCD, LED and "Self-powered Smart Kit." (a) The LCD lights up and the "Sungkyunkwan University" logo is displayed using the output power generated by WTNG. (b) The power output directly generated by WTNG lights up six LEDs at the same time. (c) Power controller switch that is put in the pocket. (d) Insert the multi-layer stacked WTNG into the jacket. (e) In the keyless vehicle entry system, a commercial capacitor (1200 F) charged only by WTNG is used for remote operation without any help from an external charging source.
Compared with previous research equipment, the problem with this design is that the adhesion between the textile and the nanostructure is weak, resulting in low mechanical durability. In the current work, researchers have overcome these durability problems by using bottom-up nanostructures of ZnO nanorods and PDMS nano pattern coatings.
Professor Kim concluded, "Friction power generation is a promising new energy collection method. It has extremely high output voltage and efficiency. At the same time, it has a low cost and a wide range of applications. Also its structure design and manufacture are simple, and it has excellent stability and sturdiness, which is very friendly to the environment. Recently, we have been looking for new materials that can produce a huge triboelectric effect, which has never been reported before. In addition, it is necessary to develop an efficient power management system. Through this system, the electrical energy generated by the WTNG can be effectively stored in textile-based energy storage platforms, such as textile batteries or super capacitors."