Presentation Information
[2G06【女子大学院生優秀賞2024】]Schematic structural analysis of honeycomb structure ultra-thin Ce-Ti-O films on Pt(111)
*XU LI1, Junji Yuhara2 (1. Institute of Materials and Systems for Sustainability, Nagoya University, 2. Department of Energy Engineering, Nagoya University)
To understand the structure of oxide quasicrystals and approximants, a detailed investigation of the honeycomb structure is essential. Therefore, the purpose is to elucidate the atomic structure of the Ce-Ti-O honeycomb structure. The Ce-Ti-O honeycomb ultrathin film was prepared by depositing 0.5 ML Ce and 2 ML Ti on Pt(111), followed by annealing in an oxygen atmosphere and vacuum. Honeycomb superstructure was confirmed by STM images and LEED patterns. Based on the Ti2O3 honeycomb structure, Ce atoms are situated at hollow sites in the Ti–O honeycomb network. DFT calculations confirmed structural relaxation with vertical displacement among Ti atoms and Ce–O coordination near the cell centers. Additionally, using photoelectron holography at SPring-8 BL25SU, the reconstructed atomic positions from holograms were confirmed, and it was consistent with the theoretical model. These findings offer insight into the structural pathway from honeycomb structure to oxide quasicrystal and approximant.