The Ostwald ripening process can be used to make large-grain, high-quality perovskite thin films from lower-quality, hole-ridden ones. So say researchers from Shanghai Jiao Tong University (SJTU) in China and the National Renewable Energy Laboratory (NREL) in Colorado in the US who have used their films to make high-performance solar cells with nearly 20% power-conversion efficiency………
http://nanotechweb.org/cws/article/tech/65787