Malgorzata Plonska

PLZT:Nd3+ Ceramics for Photonic Applications

In the present work the influence of neodymium concentration (0-1at-%) and sintering conditions on 8/65/35 PLZT:Nd3+ ceramics were studied. All ceramic powders were synthesized by MOM technique from high purity raw materials (>99,9%), and subsequently sintered by free sintering and hot uniaxial pressing method. To analyze the powders and ceramics more the XRD, EDS SEM, and ferroelectric measurements were performed. Optical spectra were examined for all prepared samples, and their optical properties were analyzed using reflectance, excitation and luminescence measurements. The study gives a detailed account of the relationships between doping and preparing conditions on the basic physical and dielectric and optical properties of obtained ceramic materials.

Electrical and Mechanical Examination of PLZT/PZT Graded Structure for Photovoltaic Driven Piezoelectric Transformers

Lanthanum-modified lead zirconate titanate (PLZT) ceramic materials have gained considerable attention due to their photostriction, which is the superposition of photovoltaic and piezoelectric effects. Functionally Graded Materials (FGM) implemented in construction of Piezoelectric Transformer (PT) can be used for direct converting photonic energy to electrical one by implementing photostrictive actuators with piezoelectric generator in one graded structure of piezoelectric transformer. Possible application in electronic industry needs thoroughly electrical and mechanical characterisation of this new FGM structure constructed from the PLZT/PZT material. Measurements presented in this work reveal high electrical anisotropy of this graded structure and the Impedance Spectroscopy (IS) proved to be a method capable to present such inequality in form of well separated semicircles. Additionally, dielectric measurements demonstrated that the characteristics of the graded structure are not a simply addition of starting materials parameters but are deeply influenced by a predominantly diffusion direction. Finally, additional nano-mechanical and -electrical methods are used for clarifying the complexity of the integration process of FGMs.

Technology of PLZT Material Used for Photovoltaic Driven Piezoelectric Transformers

Ferroelectric transparent variant ceramics can be used as a base material for photovoltaic driven piezoelectric transformers. This work reports on the preparation conditions of x/65/35 PLZT ceramics for x = 0, 2, 4, 8, 10, 16, 32 at.% La, via conventional mixed oxide method. The study gives a detailed account of the relationships between technology conditions and basic physical properties of obtained PLZT samples as potential material for transformers application.

Characterization of Lead Lanthanum Zirconate Titanate Ceramics Co-Doped with Lanthanide Ions

The aim of this work was to obtain Pb0.92(La0.08)(Zr0.65Ti0.35)0.98O3 materials co-doped with two different lanthanide ions (Ln3+) and characterization how they influence on the physical properties of prepared 8/65/35 PLZT: Ln3+ ceramics. As a co-dopant, praseodymium (Pr3+) and neodymium (Nd3+) ions were used at the concentration of 0.0 and 0.5 wt.% respectively. The ceramic powders of 8/65/35 PLZT, PLZT:Pr3+ as well PLZT:Nd3+ were synthesized by conventional ceramic route, from high purity raw oxide materials (>99,9%). All compositions of the ceramic samples were sintered via single time process at Ts=1200°C/3h, by the hot uniaxial pressing method. Performed measurements have shown dependence of used dopant on structure, microstructure, and dielectric as well optical properties of the fabricated 8/65/35 PLZT: Ln3+ materials.

Luminescence Properties of Ytterbium Activated PLZT Ceramics

In the present work the influence of co-doping with ytterbium ions (for 0, 0.5, 1.5, 2.5 wt.% of Yb3+) on physical properties of 8/65/35 PLZT was studied. The ceramic powders were synthesized by the modified sol-gel method, and underwent consolidation by the pressure-less sintering techniques, in Ts=1200°C/6h. Our investigations give a detailed account of the relationships between concentrations of trivalent ytterbium ions in PLZT matrix, on their structure, microstructure, as well as luminescence properties. Near-infrared luminescence spectra at about 1020 nm were registered, which correspond to 2F5/2 - 2F7/2 transition of Yb3+. Based on decay measurements, the luminescence lifetimes for the 2F5/2 excited state of Yb3+ were determined. Luminescence decay analysis indicates that the 2F5/2 lifetime increase with increasing activator concentration (Yb3+) in PLZT ceramic matrix.

Sol-Gel Transparent PLZT Ferroelectric Ceramics

Lead lanthanum zirconate titanate (known as PLZT) ceramic powders have been prepared by the modified sol – gel method, and underwent consolidation by the hot uniaxial pressing method. Application of such technique of preparation permitted to receive fine-grained transparent PLZT x/65/35 ceramics, with x = 8 -10 La at.%. The present publication gives a detailed account of the relationships between technology and physical properties of obtained materials. To analyze all ceramics SEM, EDS and mercury porosimetry were performed, and dielectric properties were studied too. Quite wide light transparency from the visible to nearinfrared range for PLZT ceramics was detected using optical absorption and infrared spectroscopy.