Atomically thin crystal for solar cell applications

Graphene may have led the way for engineering with ultrathin materials, but other materials are now taking their place in the sun. Researchers in Austria have found that an atomically thin materials, tungsten diselenide (WSe2), may have great potential in solar cells which could be made transparent and even flexible.

Although graphene — single-layer carbon — has interesting properties for electronics, including very high conductivity, the energy levels of its non-binding electrons mean that it isn’t well suited for solar cells: it works well as a light detector, but no so well as a converter of contant solar irradiation into useful electric current. But according to Thomas Mueller and colleagues at the Vienna University of Technology, tungsten diselenide, whose structure consists of a flat plane of tungsten atoms connected by selenium atoms above and below the plane, fits the bill even better, as they explain in a paper in Nature Nanotechnology.