Perovskite thin film solar cells from multi-stage dry reactions

该项目的目标是开发和动力学量化用于太阳能电池的多组分ABX3钙钛矿薄膜的多阶段全真空生长过程。对于多组分钙钛矿膜，我们指的是合金膜中的多阳离子和多阴离子。与同时共蒸发相比，多阶段工艺对于工业制造是优选的。该过程应全干燥。不同的膜生长阶段可以是（a）前体蒸气反应，其中固态前体膜与蒸气反应形成钙钛矿膜。(b)扩散偶反应，两个或多个固态前体膜通过化学扩散反应。(c)在退火过程中，一种组分（阴离子或阳离子）被另一种组分完全或部分交换的交换反应。将研究最先进的铅基钙钛矿，也将研究有前景的锡基化合物。使用在受控温度和通量下进行的反应过程，将量化反应常数、扩散常数和活化能。在这个项目中采用的主要实验方法是在实时的原位X射线衍射，它给出了在薄膜生长过程中的相形成过程的信息。

The goal of this project is the development and kinetic quantification of multi-stage all-vacuum growth processes of multi-component ABX3 perovskite thin films for solar cells. With multicomponent perovskite films we mean multi-cations and multi-anions in an alloy film. In contrast to simultaneous co-evaporation, multi-stage processes are preferable for industrial fabrication. The processes shall be all-dry. Different film growth stages can be(a) Precursor vapor reaction where a solid state precursor film reacts with vapor forming the perovskite film. (b) Diffusion couple reaction where two or more solid state precursor films react by chemical diffusion.(c) Exchange reaction where one component (anion or cation) is fully or partly exchanged by another component during annealing processes.State-of-the-art Pb-based perovskites but also prospective Sn-based compounds shall be studied. Using reaction processes performed under controlled temperature and fluxes, reaction constants, diffusion constants, and activation energies will be quantified. The main experimental method employed in this project is in-situ X-ray diffraction in real-time which gives information on the phase formation processes during thin film growth.