In this work, Eu₂O₃-doped (CaCu₃Ti₄O₁₂)_x of low dielectric loss have been fabricated using both conventional (CS) and microwave sintering (MWS), where x = Eu₂O₃ = 0.1, 0.2, and 0.3, respectively. According to X-ray diffraction (XRD) and scanning electron microscope (SEM) reports, increasing the concentration of Eu³⁺ in the CCTO lattice causes the grain size of the MWS samples to increase and vice versa for CS. The X-ray photoelectron spectroscopy (XPS) delineated the binding energies and charge states of the Cu²⁺/Cu⁺ and Ti⁴⁺/Ti³⁺ transition ions. Energy dispersive spectroscopy (EDS) analysis revealed no Cu-rich phase along the grain boundaries that directly impacts the dielectric properties. The dielectric characteristics, which include dielectric constant (ε) and the loss (tan δ), were examined using broadband dielectric spectrometer (BDS) from 10 to 10⁷ Hz at ambient temperature. The dielectric constant was >10⁴ and >10² for CS and MWS samples at x > 0.1, respectively, with the low loss being constant even at high frequencies due to the effective suppression of tan δ by Eu³⁺. This ceramic of low dielectric loss has potential for commercial applications at comparatively high frequencies.

Lead zirconate titanate (PZT) was plasma sprayed onto various substrates of different character. Additionally, a free-standing body made by plasma spraying was investigated. X-ray diffraction analyses of a decomposition of the as-sprayed coating products detected components of the PT-PZ system as well as binary oxides—PbO and ZrO₂. Due to the comparatively complex phase character, the Curie temperature monitored by DTA, had a smeared appearance without pronounced maxima. The corresponding electrical properties are comparable with those typically observed for CaTiO₃, but are worse than the normal values of bulk PZT due to defective stoichiometry.

The goal of this study is to examine the photocatalytic ability of coatings produced by atmospheric plasma spraying (APS). The plasma gun used is a common gas-stabilized plasma gun (GSP) working with a d.c. current and a mixture of argon and hydrogen as plasma-forming gas. The TiO₂ powders are particles of about 100 nm which were agglomerated to a mean size of about 55 μm, suitable for spraying. Composition of the commercial powder is 13 wt% of TiO₂ in Al₂O₃, whereas also in-house prepared powder with the same nominal composition but with agglomerated TiO₂ and conventional fused and crushed Al₂O₃ was sprayed. The feedstock materials used for this purpose are α-alumina and anatase titanium dioxide. The coatings are analyzed by scanning electron microscopy (SEM), energy dispersion probe (EDS) and X-ray diffraction. Photocatalytic degradation of acetone is quantified for various coatings. All plasma sprayed coatings show a lamellar structure on cross section, as typical for this process. Anatase titania from feedstock powder is converted into rutile titania and α-alumina partly to γ-alumina. Coatings are proven to catalyse the acetone decomposition when irradiated by UV rays.