20.500.12556/DiRROS-21963 Surface phase diagrams of pristine and hydroxylated barium hexaferrite surfaces from first-principles atomistic thermodynamics Barium hexaferrite (BHF) is a ferrimagnet, whose hexagonal unit cell presents five iron crystallographic sites along the  -axis. At the nanoscale, BHF nanoparticles grow in the form of platelets, characterized by a low thickness along its principal magnetization axis ( -axis), displaying uniaxial magnetic anisotropy with the easy axis pointing perpendicular to the platelet. This unique property of BHF nanoplatelets has lead to a variety of novel applications, which often require surface functionalization. However, it has been observed that the nanoplatelets display two different surface morphologies depending on the stage/conditions of preparation. To ground these experimental observations, we employ the ab initio thermodynamics framework to perform a systematic investigation of the thermodynamic stability of BHF bulk terminations under a wide range of chemical conditions. We calculate the surface phase diagrams of pristine and hydroxylated bulk terminations along the  -axis. For pristine terminations, two different iron terminated surfaces are preferred: the barium containing 2b termination (Ba-rich conditions) and the 4f iron terminated surface (Ba-poor conditions). In the presence of water, the hydroxylated oxygen-terminated surfaces (12k-O) are identified as the most stable ones at Ba-poor conditions and low pH values, whereas the hydroxylated 2b surface is preferred at high pH and Ba-rich conditions. termodinamika nanomateriali atomi barijev heksaferit hidrotermalna sinteza sinteza true false false Elsevier Nizozemska Angleški jezik Slovenski jezik © 2023 Elsevier B.V. Neznano 2025-04-15 10:14:09 2025-04-15 10:14:10 2025-10-24 03:50:15 0000-00-00 00:00:00 2023 0 0 Nasl. z nasl. zaslona; Opis vira z dne 30. 6. 2023; str. 1-12 [article no.] 157890 Vol. 637 2023 0000-00-00 PreprintDelovna Objavljeno NiDoloceno 0000-00-00 0000-00-00 2023-06-27 542.913 1873-5584 doi.org/10.1016/j.apsusc.2023.157890 157316867 https://www.sciencedirect.com/science/article/pii/S0169433223015696?via%3Dihub 1 9ca2c0f9-19d1-11f0-963a-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=31682 RAZ_Poberznik_Matic_2023.pdf RAZ_Poberznik_Matic_2023.pdf Raziskovalni podatki so na voljo na strani: https://zenodo.org/records/14718425. 1 A40AC9EFD590488C72D070DA51F133BB 012c19e3534aa6a8d60abf04331b7b1638d9754e25ffe334eb703102ea5c67bd edb606db-19d3-11f0-963a-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=31684 Institut Jožef Stefan 0 0 0