Raman spectroscopy real-time detection for the performance of perovskite solar cell

In this work, Raman signals are used to characterize the crystallinity of perovskite films and the photoelectric conversion efficiency (PCE) of perovskite solar cells. By controlling the ratios of EtOH and CHCl3 during the perovskite crystallization process, the CH3NH3PbI3 film with larger crystal grain size, higher crystallinity and no pinholes can be obtained. Good crystallinity of perovskite films promotes charge transfer (CT), and Raman spectroscopy is a practical method for the real time detection of CT in perovskite films. The results manifest that SERS intensities are conforming to X-ray diffraction (XRD) intensities and the PCE of perovskite solar cells. Meanwhile, the Raman signals are tested in the nitrogen environment, which can avoid the decomposition of perovskite films caused by H2O and O2. These results indicate that this method provides an early, real-time and harmless method to study the performance of perovskite photovoltaic devices.