Solar cells made out of a perovskite-structured compound are the fastest-growing solar technology to date. Compared to traditional silicon solar cells, the raw materials used are cheap to produce, simple to manufacture, and their efficiencies are very high making them commercially attractive and a very promising material for high-efficiency optoelectronic applications. However, some of the physical and chemical properties of these materials, which are critical to improving performance, are still not fully understood. Very recently, researchers from the US Department of Energy’s Oak Ridge National Laboratory in Tennessee have employed a unique combination of imaging and characterization tools and atomic-level simulations to solve a longstanding debate about the internal structure of these fascinating materials.
The all-inorganic perovskite solar cells are built in several layers. The bottom layer is glass, which is several millimeters thick. The second layer is a transparent conductive material called FTO. Then comes an electron sensitive layer made from titanium oxide. The fourth layer is the photoactive perovskite. Finally, the top layer is carbon.Credit: OISTAmong the many techniques used was ZEISS ORION NanoFab SIMS – a unique multiple ion beam microscope capable of generating both helium and neon ion beams to acquire extremely surface sensitive images with very high resolution (