Researchers from Ohio State University managed to create a one-atom-thick sheet of Germanium (called Germanane). This new material's structure is closely related to graphene, and it conducts electrons more than ten times faster than silicon and five times faster than conventional germanium. The researchers say that Germanane may enable some of the benefits of graphene and other new materials, but it will be much cheaper to cost as it's a material already used widely.
The researchers created multi-layered germanium crystals that have calcium atoms wedged between the layers. The calcium was then dissolved (using water), and the empty chemical bonds were "plugged" with hydrogen. Then they were able to peel off single germanane sheets. The hydrogen atoms makes germanane sheets very chemically stable (unlike "normal" sheets) - even more so than silicon as it won't oxidize in air or water.
Germanium has a direct band-gap which makes it very useful in optoelectronics - PVs made from this material for example will be hundreds of times thinner than PVs made from indirect band-gap materials.