Article 6 – Tunable Ferroionic Properties in CeO2/BaTiO3 Heterostructures

Abstract:

Ferroionic materials combine ferroelectric properties and spontaneous polarization with ionic phenomena of fast charge recombination and electrodic functionalities. In this paper, we propose the concept of tunable polarization in CeO2−δ (ceria) thin (5 nm) films induced by built-in remnant polarization of a BaTiO3 (BTO) ferroelectric thin film interface, which is buried under the ceria layer. Upward and downward fixed polarizations at the BTO thin film (10 nm) are achieved by the lattice termination engineering of the SrO or TiO2 terminated Nb:SrTiO3 (NSTO or STN) substrate. We find that the ceria layer punctually replicates the polarization of the BTO interface via a dynamic reconfiguration of its intrinsic defects, i.e., oxygen vacancies and small polarons. Tunable oxidative or reducing properties (redox) also arise at the surface from the built-in polarization. Opposite polarities at the ceria termination tune the chemo-physical dynamics toward water molecule adsorbates. The inversion of the surface potential leads to a modulation of the water adsorption−desorption equilibrium and water ionization (splitting) redox overpotentials within ±400 mV at room temperature, depending on the ceria termination’s charges. Such tunability opens up the perspectives of using ferroionics for wireless electrochemically enhanced catalysis.

 

Title: Tunable Ferroionic Properties in CeO2/BaTiO3 Heterostructures

Authors: Milica Vasiljevic, Francesco Chiabrera, Denis Alikin, Federico Motti, Achilles Bergne, Javier Zamudio-García, Xueping Qin, Deepak Dagur, Shinhee Yun, David Marrero-López, Giovanni Vinai, Ivano Castelli, Andrei Kholkin, and Vincenzo Esposito

Reference: ACS Appl. Mater. Interfaces 2024, XXXX, XXX, XXX-XXX

DOI: https://doi.org/10.1021/acsami.4c09477

Related Posts

Article 12 – Flexocoupling-induced phonons and ferrons in van der Waals ferroelectrics

Abstract: The contribution of flexoelectric coupling to the long-range order parameter fluctuations in ferroics can be critically important to the ferron dispersion and related polar, pyroelectric, and electrocaloric (EC) properties. Here, we calculate analytically the dispersion relations of soft optic and acoustic flexocoupling-induced phonons and ferrons by incorporating the flexoelectric

Read more »

Article 11 – Quantitative 3D Optical Birefringence in Peptide Bioelectrets

Abstract: Peptide nanotubes (PNTs) are bioelectrets that exhibit piezoelectricity, pyroelectricity, ferroelectricity, and birefringence. Birefringence is an optical property that can be used to determine the degree of order, orientation, size, and shape of PNTs. In this work, a custom-built optical apparatus is used to quantitatively measure birefringence in three dimensions

Read more »

Book Chapter 1 – Organic and Biological Piezoelectric Materials

Abstract: Natural organic piezoelectric materials have been the subject of intense research over the last couple of decades. This interest is due to their remarkable piezoelectric characteristics, biocompatibility, biodegradability, outstanding mechanical properties, and cost-effective fabrication processes. This chapter presents an extensive overview about the recent advances in natural organic piezoelectric

Read more »

Article 10 – Electromechanical coupling in polaronic ceria

Abstract: Oxygen-defective metal oxides like cerium oxides exhibit giant electrostriction and field-induced piezoelectricity due to a dynamic electrosteric interplay between oxygen defects, V··O, and the fluorite lattice. While such mechanisms are generally attributed to oxygen vacancies, recent results also highlight that trapped cationic defects, Ce′Ce, i.e. small polarons, can contribute

Read more »

Article 9 – Strain-Polarization Coupling in the Low-Dimensional Van der Waals Ferrielectrics

Abstract: Using the Landau-Ginzburg-Devonshire phenomenological approach we explore the strain-polarization coupling in the low-dimensional van der Waals ferrielectrics. We evolve the analytical model of the piezoelectric susceptibility of the material in response to the periodic strain modulation, such as caused by a surface acoustic wave. Numerical calculations are performed for

Read more »

Article 8 – Coexistence and interplay of two ferroelectric mechanisms in Zn1-xMgxO

Abstract: Ferroelectric materials promise exceptional attributes including low power dissipation, fast operational speeds, enhanced endurance, and superior retention to revolutionize information technology. However, the practical application of ferroelectric-semiconductor memory devices has been significantly challenged by the incompatibility of traditional perovskite oxide ferroelectrics with metal-oxide-semiconductor technology. Recent discoveries of ferroelectricity in

Read more »