Non-technical Abstract The lead halide perovskites possess the electrical and optical properties of conventional semiconductors, but unlike most semiconductors they can be prepared by simple inexpensive methods including deposition from solution. They are attractive for many applications, the most exciting of which is in solar cells where the efficiencies have 20% and are now comparable to single crystal silicon solar cells. Their biggest liability is the toxicity that comes from the presence of lead. With the support of the Solid State and Materials Chemistry program, the proposed research aims to discover and develop halide double perovskites, an emerging class of semiconductors that possess many of the favorable characteristics of the lead halide perovskites, but without the presence of toxic elements like lead. In this way the research aims to dramatically increase the feasibility and sustainability of halide perovskites for technological applications.
New materials will be found via computationally guided exploratory synthesis. Detailed characterization of the optical and electrical properties will provide the necessary feedback to design materials with properties that are optimized for applications. The proposed research will significantly expand the scope of the halide double perovskites producing materials whose band gaps continuously span the spectral range from UV to near-infrared. Growth of single crystals and thin films will provide a fundamental understanding of the carrier mobilities, lifetimes, and diffusion lengths in this class of materials. By finding materials with appropriate band gaps materials will be developed that can compete with the lead halide perovskites for use in solar cells and other applications including quantum dots, scintillators, and transparent conductors.
