STEM imaging of La3Te4 samples hot-pressed at different temperatures for grain size analysis

Content: STEM imaging for grain size analysis for La3Te4 thermoelectric samples obtained via hot pressing at 900 °C (sample folder labelled with 900 C), 1000 °C (sample folder labelled with 1000 C), and 1100 °C (sample folder labelled with 1100 C). The Excel file GrainSize.xslx contains the data analysis. Collection and analysis method: Scanning Transmission Electron Microscopy (STEM) was performed with a Thermo Fisher Titan Themis probe-corrected microscope operated at 300 kV. A STEM probe of convergence angle of 24 mrad was used, and an Annular Bright Field detector with a collection angle between 10 to 16 mrad was employed. These setting were employed to enhance the diffraction contrast between different grains and crystal defects. STEM lamellae were prepared via Ga+ focused ion beam (FIB) in a Scios2 dual beam microscope. Source article: Duncan Zavanelli, Eleonora Isotta, Ruben Bueno Villoro, Siyuan Zhang, Christina Scheu, Sabah Bux, G. Jeffrey SnyderMetallic Grain Boundary Resistance in the High Temperature Thermoelectric La3Te4,Journal of Materiomics, 2025, 101116, ISSN 2352-8478,https://doi.org/10.1016/j.jmat.2025.101116.(https://www.sciencedirect.com/science/article/pii/S2352847825001066) Funding: Project “MetaSCT: Metamaterials for Thermoelectric Applications - multiscale Structure, Chemistry, Thermal Property relations to uncover the local behavior of grain boundaries” under HORIZON Europe: Marie Skłodowska-Curie Actions Postdoctoral Fellowships (project number 101150912).