High Resolution: STEM can achieve sub-angstrom resolution, allowing for the visualization of individual atoms. Elemental Analysis: Combined with energy-dispersive X-ray spectroscopy (EDS) and electron energy loss spectroscopy (EELS), STEM can provide detailed elemental composition and chemical state analysis. 3D Imaging: STEM tomography can be used to reconstruct three-dimensional images of the sample, providing a comprehensive understanding of the catalyst's structure.