Oxygen vacancy generation and structural stability of MgO partially-stabilized zirconia upon MnO2 addition. (8th December 2017)

• Record Type: Journal Article
• Authors: Kim, Buyoung; Ryu, Jiseung; Jeon, Seol; Lee, Heesoo
• Is Part Of: Materials research express. Volume 4:Number 12(2017)
• Publication Date: 2017-12-08
• Subjects: MgO partially-stabilized zirconia -- valence state change -- distorted Zr–O coordination -- phase stability -- MnO2 addition; Materials science -- Research -- Periodicals; Materials science -- Periodicals; 620.11
• DOI: 10.1088/2053-1591/aa6b7d
• Languages: English
• ISSNs: 2053-1591

Abstract

Abstract: The phase stability of MgO partially-stabilized zirconia (MgPSZ) with Mn doping was studied in terms of the valence state and the local atomic structure. Increase of cubic phase in MgPSZ consistent with monoclinic and cubic mixed phase by MnO2 addition was observed by morphology and x-ray diffraction, and the 10 mol% doped sample exhibited 98% cubic phase fraction, a level of fully cubic stabilized zirconia. Valence state of Mn ion in MgPSZ was reduced from Mn 4+ to Mn 2+ with increase in Mn content, which led to generation of oxygen vacancy due to charge compensation. The coordination of Zr–O bonding was identified through Zr K-edge extended x-ray absorption fine structure and the bonding was decrease by the oxygen vacancy generation with up to 10 mol% Mn doping. It was considered that the oxygen vacancy formed by Mn doping released the distortion of Zr–O coordination, which affected the cubic phase stability by transformation of monoclinic to cubic phase.