“This type of flexible energy storage device could provide unique opportunities for connectivity among wearable and internet of things devices,” said Seung Woo Lee, an assistant professor at Georgia Tech. “We also have an opportunity to combine this supercapacitor with energy-harvesting devices that could power biomedical sensors, consumer and military electronics and similar applications.”
The process uses an amine surfactant to bind gold nanoparticles to the paper. Using a repeating process, the researchers created a conductive paper on which alternating layers of metal oxide energy storage materials were added.
“It’s basically a very simple process,” Lee said. “We can fold the resulting metallised paper and otherwise flex it without damage to the conductivity.”
The self-assembly technique is said to improve several aspects of paper supercapacitors, including areal performance. The maximum power and energy density of the metallic paper-based supercapacitor is estimated to be 15.1mW/cm 2 and 267.3μWh/cm2 – said to be better than conventional paper or textile supercapacitors.
The next steps will include testing the technique on flexible fabrics and developing flexible batteries that could work with the supercapacitors. “We have nanoscale control over the coating applied to the paper,” Lee added. “If we increase the number of layers, the performance continues to increase. And it’s all based on ordinary paper.”
