Demonstration of a Gandolfi-type attachment for fast high-resolution synchrotron XRD of non-ideal specimens

Abstract

Abstract Synchrotron powder X-ray diffraction (PXRD) offers significant advantages in the structural analysis of functional materials and enables the acquisition of high-quality data; however, accurate data collection remains challenging for samples consisting of coarse crystallites or molten samples. Specifically, obtaining reliable PXRD data from samples in their as-solidified or non-pulverized state remains challenging during melting–solidification and crystal grain growth processes, as well as for materials produced by these processes. To mitigate these limitations, a two-axis rotation Gandolfi-type attachment—comprising a 45°-tilted φ -axis and its rotational ω -axis—was developed and implemented on a high-resolution powder diffractometer at SPring-8, which is equipped with fast area detectors. This configuration improved the particle statistics by increasing the number of crystallites satisfying the Bragg condition through two-axis rotation, while also stabilizing the sample position, even for molten samples, owing to the tilted geometry. Specifically, the integration of a high-speed spinner and multiple two-dimensional photon-counting detectors allowed sub-second continuous imaging and frame-by-frame peak separation, facilitating the indexing of PXRD data for complex structures. The analytical capability was evaluated in three case studies, namely the pair distribution function analysis of molten Zn, in situ observations of LiCoO 2 electrode material synthesis in a molten flux, and high-resolution PXRD of mineral crystals within a short timeframe. The results confirmed that the Gandolfi-type attachment improved data quality and reproducibility, thereby enabling reliable measurements even for practical samples with limited availability of fine powders.