Work

Controlling graded microstructures in BaTiO3 with applied electric fields: Reversing grain-size gradients

Year: 2025

Type: article

Abstract: Graded microstructures form in BaTiO₃ under applied electric fields, with the polarity of the gradient reversing as the voltage increases. At 5 V, grain growth is enhanced on the anode side, whereas at 15 V it shifts to the cathode side. Advanced electron microscopy was employed to characterize grain boundaries (GBs) and clarify the underlying mechanisms. At 5 V, anode-side enhancement is attributed to elevated concentrations of cation vacancies, nonstoichiometric GBs, and/or reduced GB space charges. At 15 V, cathode-side reduction, facilitated by SiO 2 segregation and an increased specimen temperature from Joule heating at this higher applied voltage, induces a GB disordering transition, forming glass-like intergranular films that enhance GB mobility and reverse the polarity of the graded microstructure. These findings reveal new mechanisms of electric-field–induced GB transitions, demonstrate how electric fields can be exploited to tailor microstructures, and advance the fundamental interfacial science of GB phase-like (complexion) transitions.

Source: Journal of the European Ceramic Society

DOI: 10.1016/j.jeurceramsoc.2025.118104

Authors: Keqi Song, Jingjing Yang, Keyu Cao, Sashank Shivakumar, Jian Luo

Institution: University of California San Diego

Language: English

Topic: Ferroelectric and Piezoelectric Materials

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,900

Funder: Air Force Office of Scientific Research