Researchers from the University of South Carolina have modified the fabric in a t-shirt so that it can store an electrical charge. This could lead to the development of a wearable cotton t-shirt that could charge your smartphone. Xiaodong Li, a professor of mechanical engineering at USC, sees a future where electronics are part of our wardrobe.
Li says, "We wear fabric every day. One day our cotton T-shirts could have more functions; for example, a flexible energy storage device that could charge your cell phone or your iPad."
Li and post-doctoral associate Lihong Bao reported
in the journal Advanced Materials
how to turn the material in a cotton T-shirt into a source of electrical power. Starting with a T-shirt from a local discount store, Li's team soaked it in a fluoride solution, dried it and baked it. They excluded oxygen in the oven to prevent the material from charring or combusting.
The surfaces of the resulting fibers in the fabric were shown by infrared spectroscopy to have been converted from cellulose to activated carbon. The material retained flexibility and could still be folded without breaking. By using small swatches of the fabric as an electrode, the researchers showed that the material, which Li's team calls "activated carbon textile," acts as a capacitor. Li's team then coated the individual fibers in the activated carbon textile with "nanoflowers" of manganese oxide. This nanometer thick layer of manganese oxide greatly enhanced the electrode performance of the fabric.
The researchers say the coated hybrid fabric improved the energy storage capability beyond the activated carbon textile alone. The hybrid supercapacitors were very resilient. The researchers found that even after thousands of charge-discharge cycles, performance didn't diminish more than 5 percent.
Li says, "By stacking these supercapacitors up, we should be able to charge portable electronic devices such as cell phones."
Photo: Xiaodong Li/University of South Carolina