Ferroelectric electron emission has two possible sources: rapid polarization switching and surface plasma discharge. The present paper uses an X-ray diffraction (XRD) method to support the theory of rapid polarization switching for lead zirconate titanate samples. A decrease in the 002 peak value and an increase In the 200 peak value were observed after electron emission in two types of samples, which were doped with lanthanum and neodymium, A comparison of the XRD data for the samples showed that a high-density electron emission was related to a high-value polarization switch. These results were consistent with the theory of rapid polarization switching.