Giant electrostriction in bulk RE (III) substituted CeO2: Effect of RE-[formula omitted] interaction and RE concentration

Abstract

Recent discovery of giant electrostriction in bulk polycrystalline ceramics and thin films of rare earth (RE (III)) substituted ceria (CeO2) driven by electroactive defect complexes and their coordinated elastic response, expands the material spectrum for electrostrain applications beyond the conventional piezoelectric materials. Bulk ceramics provide an ideal platform to systematically study electrostriction as a function of parameters such as RE3+-defect (VO••) interaction and RE concentration. In this work, we perform structure-property correlation studies in bulk ceramics of RE3+ substituted ceria (RECO) with RE=Y, La and Gd, all of them having weak dopant-defect interaction, with Y- VO•• being attractive, La-VO•• being repulsive, and Gd-VO•• being neutral. We employ large signal measurements to measure the electrostrictive coefficients of all the RECO ceramics, with varying concentration of RE3+, and show that an attractive defect-dopant interaction with atleast 20% of substituent ion concentration yields both giant M and Q electrostrictive response.