Giving Graphene a Rest

A pristine sheet of graphene has many interesting electronic properties, but they can be lost when the material is supported on a substrate, as it has to be in most experiments and practical devices. The best substrates so far—graphite and hexagonal boron nitride (hBN)—both have limitations; in particular, hBN is known to cause a spatial modulation in graphene’s electronic structure. Now, researchers in Eva Andrei’s group at Rutgers University, New Jersey, have identified molybdenum disulfide (MoS2), a semiconductor that cleaves easily into atomically smooth sheets, as a promising substrate. The material could be particularly well suited as a substrate in spintronics devices, which require a perfect landscape for graphene’s electrons.