Researchers looking to hydrogen as a next-generation clean energy source are developing hydrogen-sensing technologies capable of detecting leaks in hydrogen-powered vehicles and fueling stations before the gas turns into an explosion. The most common type of hydrogen sensors is composed of palladium-based thin films because palladium (Pd), a silvery-white metal resembling platinum, readily absorbs hydrogen gas. However, Pd also readily absorbs other gases, decreasing the overall efficiency of these sensors.