Combined theoretical and nanoscale experimental study of Pb(Ca,Ba)TiO3, Pb(Sr,Ba)TiO3, and Pb(Sr,Ca)TiO3 complex perovskite structures: An investigation of the ferroelectric and electronic properties

Abstract

Combined experimental and first-principles studies have been conducted to obtain a fundamental understanding of the effect of A-site chemical doping on the electronic structure and ferroelectric behavior of Pb(Ca,Ba)TiO 3 , Pb(Sr,Ba)TiO 3 , and Pb(Sr,Ca)TiO 3 perovskite complex solid solutions. Rietveld refinement of powder X-ray diffraction data shows that the crystal structure of all the three compounds is distorted from the ideal cubic perovskite structure. At the nanoscale, piezoresponse force microscopy (PFM) studies show low-performance ferroelectric properties of Pb(Sr,Ca)TiO 3 thin films when compared to Pb(Ca,Ba)TiO 3 and Pb(Sr,Ba)TiO 3 films. Theoretical analysis of the electronic band structure performed on the basis of density functional theory (DFT) allows to elucidate the origin of the different ferroelectric behaviors observed in Pb(Ca,Ba)TiO 3 , Pb(Sr,Ba)TiO 3 , and Pb(Sr,Ca)TiO 3 thin films. DFT-based computational calculations reveal that there is a strong correlation between the effects of Ti 3d non-bonding orbitals (responsible for p TieO bonding) and the ferroelectric polarization behavior of A(A 0 A 00)BO 3 complex perovskite solid solutions. In our study, very low Ti 3d xy, d xz , and d yz non-bonding electronic density state contributions were observed and the presence of mainly ionic CaeO and SreO bonds. These effects are the reason for the unusually weak polarization, low tetragonality, and poor ferroelectricity of Pb(Sr,Ca)TiO 3 thin films. This is in contrast to the observed behaviors of Pb(Ca,Ba)TiO 3 and Pb(Sr,Ba)TiO 3 thin films. However, our first-principles calculations agree well with the PFM-based experimental results obtained in the nanometer scale.

Advanced materials and technologies for supercapacitors used in energy conversion and storage: a review

“…The inorganic perovskite-type oxides show special physicochemical characteristics in ferroelectricity (Pontes et al 2017;Rana et al 2020;Cao et al 2017), piezoelectricity (Perumal et al 2019;Vu et al 2015;Xie et al 2019), dielectric (Arshad et al 2020;Zhou et al 2019;Boudad et al 2019), ferromagnetism (Yakout et al 2019;Ravi and (Wang et al 2015a;Liu et al 2007;Dwivedi et al 2015), and multiferroic (Li et al 2019b;Zhang et al 2016b;Pedro-García et al 2019). They are interesting nanomaterials for broad applications in catalysis (Grabowska 2016;Yang and Guo 2018;Hwang et al 2019;Xu et al 2019a;Ramos-Sanchez et al 2020), fuel cells (Kaur and Singh 2019;Sunarso et al 2017;Jiang 2019), ferroelectric random access memory (Gao et al 2020;Chen et al 2016a;Wang et al 2019a), electrochemical sensing and actuators (Govindasamy et al 2019a;Deganello et al 2016;Atta et al 2019;Zhang and Yi 2018;Rosa Silva et al 2019), and supercapacitors (Song et al 2020;Salguero Salas et al 2019;Lang et al 2019;George et al 2018).…”

On the coexistence of ferroelectric and antiferroelectric polymorphs in NaNbO3 fibers at room temperature

“…16,25 Piezoresponse force microscopy (PFM) is a powerful tool for investigating the ferroelectricity of bulk materials, as well as materials at the nanoscale level (nanostructures and thin films). [26][27][28][29][30][31] In the last few decades, PFM has allowed comprehensive studies on the processes of electrical polarization and wall dynamics of the ferroelectric domains, 32,33 switching of polarization and nucleation domains, 34,35 and the behavior of ferroelectric properties with different parameters in the preparation of materials. [36][37][38] Thus, in this context, this work is a thorough study of the structure of one-dimensional NaNbO 3 based on a set of experimental characterization techniques and an atomistic computational approach.…”