SusChEM: Halide Double Perovskites a New Class of Lead-Free Compound Semiconductors

卤化铅钙钛矿具有传统半导体的电学和光学特性，但与大多数半导体不同的是，它们可以通过简单廉价的方法制备，包括从溶液中沉积。它们在许多应用中都很有吸引力，其中最令人兴奋的是在太阳能电池中，效率达到20%，现在可以与单晶硅太阳能电池相媲美。它们最大的缺点是铅的毒性。在固态和材料化学计划的支持下，拟议的研究旨在发现和开发卤化物双钙钛矿，这是一种新兴的半导体，具有铅卤化物钙钛矿的许多有利特征，但没有铅等有毒元素的存在。通过这种方式，研究旨在显著提高卤化物钙钛矿技术应用的可行性和可持续性。技术摘要：通过计算指导探索性合成，将发现新材料。光学和电性能的详细表征将为设计具有优化应用性能的材料提供必要的反馈。提出的研究将显著扩大卤化物双钙钛矿生产材料的范围，其带隙连续跨越从紫外到近红外的光谱范围。单晶和薄膜的生长将为这类材料的载流子迁移率、寿命和扩散长度提供基本的理解。通过寻找具有适当带隙的材料，将开发出可以与卤化铅钙钛矿竞争的材料，用于太阳能电池和其他应用，包括量子点，闪烁体和透明导体。

Non-technical AbstractThe 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. Technical AbstractNew 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.