Electron Spectroscopy and Microscopy: A Window into the Surface Electronic Properties of Polycrystalline Metal Halide Perovskites

• Published in: Advanced materials (Weinheim) 2024-07, Vol.36 (28), p.e2310240-n/a
• Main Authors: Wong, E Laine, Folpini, Giulia, Zhou, Yang, Albaqami, Minirah Dukhi, Petrozza, Annamaria
• Format: Article
• Language: English
• Subjects: Band structure of solids; crystal momentum; Electron spectroscopy; electronic band structure; metal halide perovskites; Metal halides; Optical properties; Perovskites; Photoelectric emission; polycrystallinity; Polycrystals; Single crystals; Thin films
• ISSN: 0935-9648; 1521-4095; 1521-4095
• DOI: 10.1002/adma.202310240

In the past years, an increasing number of experimental techniques have emerged to address the need to unveil the chemical, structural, and electronic properties of perovskite thin films with high vertical and lateral spatial resolutions. One of these is angle‐resolved photoemission electron spectroscopy which can provide direct access to the electronic band structure of perovskites, with the aim of overcoming elusive and controversial information due to the complex data interpretation of purely optical spectroscopic techniques. This perspective looks at the information that can be gleaned from the direct measurement of the electronic band structure of single crystal perovskites and the challenges that remain to be overcame to extend this technique to heterogeneous polycrystalline metal halide perovskites. The perspective presents an overview of the array of information that can be gleaned from the characterization of single crystals of metal halide perovskites using electron spectroscopic techniques. Building on this information, the perspective then discusses the challenges that need to be addressed in order to extend these versatile techniques to include the highly heterogeneous polycrystalline perovskite thin films.