MXenes guard against electromagnetic interference

Cell phones and other electronic gadgets emit electromagnetic radiation that can cause the annoying buzzing often heard through television, radio, and computer speakers. Device manufacturers try to protect their products from this stray electromagnetic interference, referred to as EMI, and reduce the interference their gadgets cause by using a shielding material such as a layer of copper or aluminum. Electronics makers may soon be able to use less expensive, thinner, and lighter EMI shielding thanks to a newly discovered property of a family of two-dimensional metal carbides and nitrides (Science 2016, DOI: 10.1126/science.aag2421). Referred to as MXenes (pronounced “max-eens”), these strong, flexible, and electrically conducting materials are being studied for use in batteries and flexible electronics. A team led by Drexel University’s Yury Gogotsi now finds that, on a weight and thickness basis, films of Ti₃C₂T_x, Mo₂TiC₂T_x, and Mo₂Ti₂C₃T_x (T represents OH and F surface terminations) provide EMI protection nearly as effectively as or better than pure metals and far better than carbon fibers, nanotubes, and other synthetic materials that have been studied for this application. In addition, MXenes, which can be incorporated into polymer composites, are easily processed in solution and can be sprayed onto irregularly shaped devices.