Halide perovskite based solar cells are a recent ground-breaking breakthrough of power conversion efficiencies exceeding 20%. This is possible because ABX3 (A = 1+ alkali metal or small molecule; B = 2+ metal cation and X = halogen anion) exhibits strong light absorption, high carrier mobility, and long carrier lifetimes for both electrons and holes. Recent theoretical results show that these superior properties are mostly governed by low energy electronic structures, where B-site metals are crucial; both orbital hybridization and spin-orbit coupling (SOC) of B-site metal atom play important roles to determine optical as well as transport properties. However, the B-site atom of the usual halide perovskite solar cell is lead, which is known as a toxic chemical element to human. Now it becomes a key issue to find the alternatives to replace the lead in the halide perovskite solar cells. In this study, we investigate the various combinations of mixed cations to replace the lead element at B-site of the halide perovskite, via the high-throughput computational screening method based on the first principles alculations. I will discuss the potential candidates of lead-free halide perovskite for solar cell applications.
Biography
Jino Im obtained his Ph. D. in physics from Seoul National University in 2009. From 2009-2014, he was a postdoctoral scholar in the department of physic at University of California, Davis, and in the department of physics at Northwestern University. He is currently a senior researcher at Korea Research Institute of Chemical Technology. His research focuses on studying electronic structures of novel materials for electronic/chemical devices and energy harvesting.