Publications by authors named "Andrei N Salak"

In the last decade, organic-inorganic hybrid halide perovskite materials have developed into a very large research area in photovoltaics and optoelectronics as promising light harvesters. Lead-free double perovskites have recently been investigated as an environmentally friendly alternative to the lead-containing compositions. However, lead-free organic-inorganic hybrid halide double perovskites have so far rarely been produced due to a certain complexity in their synthesis.

View Article and Find Full Text PDF

Dicalcium phosphate dihydrate (CaHPO·2HO, DCPD, brushite) crystals were synthesised within Scots pine sapwood a wet-chemistry route from aqueous solutions of Ca(CHCOO) and NHHPO salts. SEM/EDS analysis was used to assess the saturation of the wood cell lumina and cell wall as well as morphological features and elemental composition of the co-precipitated mineral. Brushite mineral crystallization and crystallite growth within the wood matrix was studied by XRD.

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on how magnetic fields influence the formation of cobalt-aluminium layered double hydroxides, leading to the precipitation of tiny crystal structures.
  • When a magnetic field is applied perpendicular to the surface, it results in the creation of dense and uniform films of these materials.
  • The unique magnetic properties of the crystallites are attributed to a shift in the arrangement of cations, particularly favoring a honeycomb-like structure for cobalt ions.
View Article and Find Full Text PDF

Multiferroic materials demonstrating coexistence of magnetic and ferroelectric orders are promising candidates for magnetoelectric devices. While understanding the underlying mechanism of interplaying of ferroic properties is important, tailoring their properties to make them potential candidates for magnetoelectric devices is challenging. Here, the antiferromagnetic Neel ordering temperature above 200 K is realized in successfully stabilized epitaxial films of (Lu,Sc)FeO multiferroic oxide.

View Article and Find Full Text PDF

The temperature behavior of the crystal structure as well as dielectric and magnetic properties of the perovskite bismuth chromate ceramics with the 10 mol % Cr-to-Sc substitution were studied and compared with those of the unmodified compound. Using a high-pressure synthesis, BiCrO and BiCrScO were obtained as metastable perovskite phases which are monoclinic 2/ with the √6 × √2 × √6 superstructure (where is the primitive perovskite unit-cell parameter) under ambient conditions. At room temperature, the unit cell volume of BiCrScO is ∼1.

View Article and Find Full Text PDF

We report that luminescence of Eu ion incorporated into Ruddlesden-Popper phases allows monitoring phase transition in powders (instead of single crystals), in a time-efficient manner (compared to neutron diffraction), and importantly, with greater sensitivity than previous methods. Crystal structure and dielectric response of undoped and 0.5%Eu-doped SrSnO ceramics were studied as a function of temperature over the temperature range of 300-800 K.

View Article and Find Full Text PDF

Single-phase magnesium-aluminium layered double hydroxide (LDH) intercalated with dihydrogen phosphate was successfully produced by hydration of nanopowder of the respective mixed metal oxide (MMO) obtained using sol-gel based method followed by a two-step anion exchange hydroxide-to-chloride and chloride-to-phosphate. The MMO with the metal cation ratio of Mg/Al = 2:1 was prepared using the aqueous sol-gel method. Processes of the parent MgAl-OH LDH formation and the successive anion-exchanges, ОН → Cl and Cl → HPO, were considerably accelerated via the application of high-power (1.

View Article and Find Full Text PDF

An approach for the synthesis of ZnAl-NO3 LDH conversion coatings on zinc in an aqueous acidic Al(NO3)3/NaNO3 solution is demonstrated for the first time. The growth mechanism has been investigated using time resolved structural, microstructural and analytical methods. A LDH growth model involving both electrochemical and chemical processes is suggested.

View Article and Find Full Text PDF
Article Synopsis
  • A thermal treatment after synthesis of the BiFe1-yScyO3 perovskite leads to the creation of new, stable structures that have unique magnetic characteristics.
  • These new structures include both polar and antipolar forms, showcasing interesting properties not previously observed.
  • The study suggests that this process of forming new polymorphs through annealing could occur in other materials as well.
View Article and Find Full Text PDF

Zinc-aluminum layered double hydroxides with nitrate intercalated (Zn(n)Al-NO3, n=Zn/Al) is an intermediate material for the intercalation of different functional molecules used in a wide range of industrial applications. The synthesis of Zn(2)Al-NO3 was investigated considering the time and temperature of hydrothermal treatment. By examining the crystallite size in two different directions, hydrodynamic particle size, morphology, crystal structure and chemical species in solution, it was possible to understand the crystallization and dissolution processes involved in the mechanisms of crystallite and particle growth.

View Article and Find Full Text PDF

Novel self-healing protective coatings with nanocontainers of corrosion inhibitors open new opportunities for long-term anticorrosion protection of different metallic materials. In this paper a new type of functional nanoreservoir based on silica nanocapsules (SiNC) synthesized and loaded with corrosion inhibitor 2-mercaptobenzothiazole (MBT) in a one-stage process is reported for the first time. Unlike conventional mesoporous silica nanoparticles, SiNC possess an empty core and shell with gradual mesoporosity, arising from the particular conditions of the synthetic route adopted, which confers significant loading capacity and allows prolonged and stimuli-triggered release of the inhibiting species.

View Article and Find Full Text PDF