Scientists at Pennsylvania State University in the US. a new direction in scalable energy harvesting of unused mechanical energy in the environment, including wind, ocean waves and human motion. The concept is to specifically design a way to turn low-frequency motion, such as human movement or ocean waves, into electricity this organic polymer p-n junction device Called an ionic diode, their device is composed of two nanocomposite electrodes with oppositely charged mobile ions separated by a polycarbonate membrane.
The electrodes are a polymeric matrix filled with carbon nanotubes and infused with ionic liquids.
The nanotubes enhance the conductivity and mechanical strength of the electrodes. When a mechanical force is applied, the ions diffuse across the membrane, creating a continuous direct current.
At the same time, a built-in potential that opposes ion diffusion is established until equilibrium is reached. The complete cycle operates at a frequency of one-tenth Hertz, or once every 10 seconds.
For smartphones, the mechanical energy involved in touching the screen could be converted into electricity that can be stored in the battery. Other human motion could provide the energy to power a tablet or wearable device.
"Right now, at low frequencies, no other device can outperform this one. That's why I think this concept is exciting,"
