We employed the hybrid DFT-LCAO approach as implemented in the CRYSTAL code for 135 atom supercell calculations of O vacancies with trapped electrons (known as the F centers) in three cubic perovskite crystals: SrTiO3, PbTiO3 and PbZrO3. The local lattice relaxation, charge redistribution and defect energy levels in the optical gap are compared. We demonstrate how difference in a chemical compo...

Lead vanadate PbVO3 is a polar crystal with P4mm space group at ambient conditions. It isostructural the model soft-mode driven ferroelectric PbTiO3, but differs from it by so-called 'supertetragonal' elongation of its unit cell. In this paper, we report combined study lattice dynamics Raman spectroscopy room temperature and first-principle calculations. All zone-center transverse optical (TO) ...

The composite of Graphite/PbTiO3 has been synthesized for photocatalyst and photo-electrocatalyst Methyl Orange (MO) Violet (MV) degradation using a visible light source. aims the research were to study influence pH solution, iradiation time kinetics MO MV photodegradation, voltage photoelectrodegradation MV. Composite was by sol-gel process with Titanium Tetraisopropoxide (TTIP) solution Pb(NO...

The evolution of tetragonality with thickness has been probed in epitaxial c-axis oriented PbTiO3 films with thicknesses ranging from 500 down to 24 A. High resolution x ray pointed out a systematic decrease of the c-axis lattice parameter with decreasing film thickness below 200 A. Using a first-principles model Hamiltonian approach, the decrease in tetragonality is related to a reduction of t...

High Curie temperaturepiezoelectricthin films of xBiInO3-(1-x)PbTiO3 (x = 0.10, 0.15, 0.20, and 0.25) were prepared by pulsed laser deposition. It was found that the tetragonality of films decreased with increasing BI content. The dielectric constant and transverse piezoelectric coefficient (e31,f ) exhibit the highest values of 665 and -13.6 C/m2 at x = 0.20. Rayleigh analyses were performed t...

This paper develops a statistical learning approach to identify potentially new high-temperature ferroelectric piezoelectric perovskite compounds. Unlike most computational studies on crystal chemistry, where the starting point is some form of electronic structure calculation, we use a data-driven approach to initiate our search. This is accomplished by identifying patterns of behaviour between...

Relaxor-PbTiO3 piezoelectric single crystals have been widely used in a broad range of electromechanical devices, including piezoelectric sensors, actuators, and transducers. This paper reviews the unique properties of these single crystals for piezoelectric sensors. Design, fabrication and characterization of various relaxor-PT single crystal piezoelectric sensors and their applications are pr...

We performed predictive hybrid-DFT computations for PbTiO3, BaTiO3, SrTiO3, PbZrO3 and SrZrO3 (001) surfaces, as well their BaTiO3/SrTiO3, PbTiO3/SrTiO3 PbZrO3/SrZrO3 heterostructures. According to our BO2 AO-terminated ABO3 solid in most cases, the upper layer ions relax inwards, whereas second shift upwards. Our computed surface rumpling s BO2-terminated perovskite surfaces almost always is p...