The rapidly increasing number of electronic devices has resulted in a demand for new portable power sources. Energy generation and storage technologies can be integrated into so-called self-charging power units (SCPUs), which are complementary to battery technologies and could pave the way towards sustainable and maintenance-free applications.
Triboelectric nanogenerators (TENGs), which generate a charge using friction between different materials, are very interesting for such units. They offer high output performance at high conversion efficiency and low cost. So far, this technology has been hampered by using acrylic as the substrate, which limits the specific mass/volume charge output of the final TENG device.
Zhong Lin Wang, National Center for Nanoscience and Technology (NCNST), Beijing, China, and Georgia Institute of Technology, Atlanta, USA, Chenguo Hu, Chongqing University, China, and colleagues have developed an ultra-light SCPU using a rhombic-shaped cut-paper architecture. First, the TENG was created by coating sandpaper with layers of gold and nanostructured fluorinated ethylene propylene (FEP). Then a supercapacitor was made by sandwiching a separator between two sheets of paper coated with layers of gold and graphite. The TENG and the supercapacitor were then assembled into the rhombic-shaped structure to yield the finished self-charging power unit.
With a specific volume charge output of 75 nC cm–3 (82 nC g–1), the TENG charged the supercapacitor ( ~ 1 mF) to about 1 V in 250 seconds at a working frequency of 3 Hz. The researchers successfully demonstrated their device’s usability as a power source for an electric watch, a temperature sensor, and a remote control. According to the researchers, the device could also be used in medical applications.
- Ultralight Cut-Paper-Based Self-Charging Power Unit for Self-Powered Portable Electronic and Medical Systems,
Hengyu Guo, Min-Hsin Yeh, Yunlong Zi, Zhen Wen, Jie Chen, Guanlin Liu, Chenguo Hu, Zhong Lin Wang,
ACS Nano 2017.