Researchers created the antennas, described online September 21 in Science Advances, using a water-based ink containing 1-nanometer-thick flakes of titanium carbide. The ink can be sprayed, painted or printed onto various materials, such as paper, glass or fabric, or fashioned into freestanding films.
Engineer Yury Gogotsi and materials scientists and colleagues at Drexel University in Philadelphia created bendy radio antennas by overlaying titanium carbide films onto sheets of polyester or filter paper. These films are ranged from 62 nanometers to 8 micrometers thick — up to about the width of a red blood cell. At about 6 centimeters long, these antennas send and receive radio signals at 2.4 gigahertz, a frequency commonly used for Wi-Fi and Bluetooth communications.
Gogotsi’s team also used titanium carbide films to make radio frequency identification tags, similar to the antitheft tags attached to merchandise at department stores. The researchers’ superslim ID tags can be scanned up to eight meters away.
Gogotsi says, “you can imagine unmanned stores, where every item has a simple and cheap [identification] tag, and those tags are automatically read when a customer leaves the store” to charge that person’s account.