Electron Microscopy of Perovskite Solar Cell Materials

Studies of photoactive perovskites with electron microscopes have revealed a multitude of important phenomena. The highly energetic electrons used in electron microscopy, however, have a strong tendency to degrade the materials, and great care must be taken to avoid confusing beam-induced damage with intrinsic perovskite properties. In this chapter, we give a focused and practical introduction to electron microscopy of perovskite solar cell materials. We discuss the fundamentals of signal generation and detection, how to prepare samples, and describe various electron microscope techniques, including scanning and transmission electron microscopy (SEM and TEM), cathodoluminescence (CL), electron beam-induced current (EBIC), electron backscatter diffraction (EBSD), high-resolution scanning TEM (HR-STEM), diffraction, and electron-dispersive X-ray spectroscopy (EDX). We further give examples of their use on photoactive perovskite films and devices to illustrate the wide range of information that can be obtained from electron microscopy.