The basics of electrocaloric effect (ECE) in ferroelectric or relaxor-ferroelectric materials were described. Large EC temperature changes have been measured in lead-based complex perovskites, such as PbMg1/3Nb2/3O3-PbTiO3 and (Pb1-3x/2Lax)Zr0.65Ti0.35O3 (PLZT x/65/35) High values of 2.5 K for bulk ceramics at the electric field amplitude up to 90 kV/cm and at temperatures near the dielectric permittivity vs. temperature maximum were obtained. In about 500 nm thick PLZT 8/65/35 films the direct electrocaloric measurement confirmed a giant electrocaloric effect, with the temperature change exceeding 40 K at the field amplitude of around 1100 kV/cm close to room temperature (45oC). Sodium potassium niobate-strontium titanate has been studied as an environment-friendly alternative to lead based relaxors.
B.05 Guest lecturer at an institute/university
COBISS.SI-ID: 26979111The patent describes the method for the preparation of lithium fluoride (LiF) powder containing colour centres. Powder with an average size of 160 nm and a narrow size distribution was prepared by milling of milimetre-sized crystalls of LiF. The powder was exposed to the white light beam with the energy between 3 and 15 keV (synchotron radiation) and thus between 1016 to 1019 colour centres per cm3 of the powder were actiavated. The so activated powder was transparent but if exposed to ultraviolet light, it become white. This property was used for invisible marking of various objects such as artistic works and objects in museums.
F.32 International patent
COBISS.SI-ID: 24553511The present invention lies in the field of electrocaloric energy conversion. More specifically, the present invention relates to improvements in systems and methods which employ electrocaloric materials as a source of temperature variation in electrocaloric refrigeration processes. Even more specifically, the present invention relates to the application of electrocaloric materials in combination with a working fluid communicating with a heat source and a heat sink in counter flow.
F.32 International patent
COBISS.SI-ID: 13102363This is the first text to cover all aspects of solution processed functional oxide thin-films. Chemical Solution Deposition (CSD) comprises all solution based thin- film deposition techniques, which involve chemical reactions of precursors during the formation of the oxide films, i. e. sol-gel type routes, metallo-organic decomposition routes, hybrid routes, etc.
C.01 Editorial board of a foreign/international collection of papers/book
COBISS.SI-ID: 27460647In the invited talk case studies of piezoelectric ceramics, processed from the powders synthesized by mechanochemically activated solid state synthesis are discussed. The studies inclue sodium potassium niobate tantalate and bismuth ferrite.
B.04 Guest lecture
COBISS.SI-ID: 26924071