Emission and Absorption Spectroscopic Techniques for Characterizing Perovskite Solar Cells

In the research of perovskite solar cells (PSCs), a fundamental understanding of the photoelectric conversion process is crucial for exploring mechanisms and optimizing performance, which largely relies on accurately capturing experimental phenomena. Spectral techniques, especially photoluminescence (PL) spectroscopy, time-resolved photoluminescence (TRPL) spectroscopy, photoluminescence quantum yield (PLQY) measurement, photoluminescence (PL) mapping spectroscopy, and transient absorption (TA) spectroscopy, are highly valued for their ability to provide detailed information about the material's working state. In this Review, we provide an overview of the latest advancements in these spectral techniques in PSC research. We demonstrate their advantages in monitoring the reconstruction of electronic structure, carrier dynamics, evolution of interfacial states, and separation of photogenerated charges in PSCs. Additionally, we discuss how to interpret the underlying physical and chemical processes in perovskite materials based on these spectral characterizations. Ultimately, we look forward to these techniques providing deeper insights into the further development of PSCs and their application in the field of renewable energy.