Researchers from Drexel University developed a spray that can be used to paint a "two dimensional" antennas on a surface. Traditional copper antennae typically found in small electronic devices are relatively large and thick, as they're limited by the "skin depth" effect. Curiously, the 100 nanometer titanium carbide layer researchers sprayed onto the surface seems to defy the predicted minimum required thickness, and the researchers don't really know why. The researchers claim that mass producing the antennas would be simple and cheap, but are looking into using different base materials in solvents other than water so that the antennas won't wash off surfaces. One researcher says "with respect to transparent antennas, we believe there are applications we cannot imagine." Check out a video of the tech here. The "spray-on" description is exactly what it sounds like. By dissolving MXenes in water, researchers produce a kind of water-based ink. Then, "we can just use a simple spray gun from Home Depot, and just spray the shape we want," Sarycheva says.