Scientists have developed a new type of water-proof solar cell which can provide electricity even after being soaked in water or stretched and compressed.
The finding could open the way for wearable solar cells, which will provide power to devices such as health monitors incorporated into clothing. These could include sensors that record heartbeats and body temperature, for example, providing early warning of medical problems.
Researchers, including those from the University of Tokyo in Japan, developed extremely thin and flexible organic photovoltaic cells, coated on both sides with stretchable and waterproof films, based on a material called PNTz4T. They deposited the device in an inverse architecture onto a one-micrometre-thick parylene film. The ultra-thin device was then placed onto acrylic-based elastomer and the top side of the device was coated with an identical elastomer, giving it a coating on both sides to prevent water infiltration. The elastomer, while allowing light to enter, prevented water and air from leaking into the cells, making them more long-lasting than previous experiments.
The researchers then subjected the device to a variety of tests, finding first that it had a strong energy efficiency.