Lokal struktur hos metallhalidperovskiter undersökt med vibrationsspektroskopi

Sammanfattning

Local Structure in Metal Halide Perovskites studied with VibrationalSpectroscopyThe rapid development of metal halide perovskites has during the last decade positioned the material as one of the most promising candidates for future energy technologysuch as solar cell technology, light emitting diodes, and photodetectors. Becausemetal halide perovskites are very flexible and in combination with the ease of synthesizing the material, they are particularly attractive to use for technical applications.This bachelor’s thesis aims to analyze the local structure of the metal halide perovskite EAxMA1−xPbI3 and in particular to see how the local structure is affected bythe cation composition x. By analyzing how the chemical composition affects thestructure of the material at room temperature, new knowledge is obtained, which isof purely scientific interest, but can also be used as a reference for the purpose ofoptimizing stability and efficiency of the material. The scientific method for thesestudies involves infrared (IR) spectroscopy and Raman spectroscopy, together withstudies of the materials photoluminescence.The reason behind this thesis is the stabilization challenges that currently limit thepractical application of perovskites. The well-researched material MAPbI3 exhibitsgood qualities, but is sensitive to chemical degradation. Introducing EA+ is relevantsince it shows potential to stabilize the structure, though it has not yet been studiedhow the substitution affects the properties of the material.This thesis shows how the cation composition has a direct and measurable impacton the local structure of the metal halide perovskites. The results present usefulinformation that corresponds to relevant literature. The thesis might be useful inthe next generation’s technical applications with customized features.