Dopant Concentration Controls Quasi-Static Electrostrictive Strain Response of Ceria Ceramics

• DOI: 10.1021/acsami.0c07799
• Publication Date: 2020-07-23T21:19:37Z
• Authors: Maxim Varenik; Juan Claudio Nino; Ellen Wachtel; Sangtae Kim; Ori Yeheskel; Nimrod Yavo; Igor Lubomirsky
• Keywords: Electrostriction

Electromechanically active ceramic materials, piezoelectrics and electrostrictors, provide the backbone of a variety consumer technologies. Gd- Sm-doped ceria are ion conducting ceramics, finding application in fuel cells, oxygen sensors, and, potentially, as memristor materials. While optimal design ceria-based devices requires thorough understanding their mechanical electromechanical properties, reports systematic study effect dopant concentration on behavior ceramics lacking. Here we report longitudinal electrostriction strain coefficient (M33) dense RExCe1-xO2-x/2 (x ≤ 0.25) pellets, where RE = Gd or Sm, measured under ambient conditions function within frequency range f 0.15-350 Hz electric field amplitude E 0.5 MV/m. For >100 Hz, all pellets tested, independent concentration, exhibit with magnitude order 10-18 m2/V2. The quasi-static (f < 1 Hz) for undoped is comparable magnitude, while introducing 5 mol % Sm produces an increase M33 by up to 2 orders magnitude. x 0.1 (Gd)-0.15 (Sm), Debye-type relaxation time constant (τ) 60-300 ms. inverse relationship between electrostrictive parallels anelasticity ionic conductivity indicating that partially governed ordering vacancies changes local symmetry.