Background

The Scherrer method is a typical method for evaluating the crystallite size of powder samples. The method assumes that the broadening of diffraction peaks due to crystal lattice strain can be ignored, and calculates the crystallite size based on the fact that the crystallite size in the direction perpendicular to the lattice plane of the diffraction peak is inversely proportional to the full width at half maximum of the peak. Cerium oxide (CeO₂) is a functional oxide nanoparticle used as a base material for exhaust gas cleaning catalysts and transparent electrolyte sheets. Since the performance of these materials depends on the particle size and crystallite size of the CeO₂ nanoparticles, evaluating their sizes is very important. In this example, we measured the X-ray diffraction pattern of CeO₂ nanoparticles and evaluated the crystallite size using the Scherrer method.