13 documents found, page 1 of 2
The orthorhombic-tetragonal morphotropic phase boundary in high-pressure synthe...
Salak, Andrei N.; Shvartsman, Vladimir V.; Cardoso, João Pedro; Pushkarev, Anatoli V.; Radyush, Yury V.; Olekhnovich, Nikolai M.; Khalyavin, Dmitry D.(1–x)BiMg0.5Ti0.5O3− xBiZn0.5Ti0.5O3 [(1− x)BMT–xBZT] ceramics of perovskite solid solutions, in which BMT and BZT are lead-free structural analogs of PbZrO3 and PbTiO3, respectively, have been synthesized under high pressure. It was found that the as-prepared compositions with a relative BZT content of <75 mol% are orthorhombic (space group Pnnm), while those with a BZT content above this value are tetragonal ...
Ce-substituted Mg-Al layered double hydroxides to prolong the corrosion protect...
Vieira, Daniel E. L.; Salak, Andrei N.; Ferreira, Mário G. S.; Vieira, Joaquim M.; Brett, Christopher M. A.Layered double hydroxides (LDH) have emerged as an alternative to chromates for corrosion protection by exploiting anion-exchange phenomena: the LDH releases corrosion inhibitor anions and captures the corrosive agent anions, extending the metal surface lifetime. In this work, the main aim was to promote continuation of corrosion protection after the end of the process of anion-exchange. For this purpose, ceriu...
Dielectric and infrared spectroscopy characterization of Co–Al layered double h...
Zamaraite, Ilona; Vieira, Daniel E. L.; Vieira, L. G.; Ribeiro, J. L.; Vieira, Joaquim M.; Salak, Andrei N.; Banys, JūrasLayered double hydroxides (LDHs) are natural 2D materials with promising functionalities. A comprehensive understanding of physical properties (such as electrical or optical) is critical for their current and future applications. Herein, dielectric and infrared spectroscopy to extensively characterize thermal behavior of dynamic effects in cobalt–aluminum LDH with Co-to-Al ratio of 2 and intercalated with nitra...
Interplay of magnetic properties and doping in epitaxial films of h-REFeO3 mult...
Baghizadeh, Ali; Vaghefi, Pegah Mirzadeh; Huang, Xing; Borme, Jerome; Almeida, B. G.; Salak, Andrei N.; Willinger, Marc-Georg; Amaral, Vitor B.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 rea...
Magnetic-field-assisted deposition of self-assembling crystallite layers of Co2...
Vieira, Daniel E. L.; Cardoso, João P. V.; Fedorchenko, Alexey V.; Fertman, Elena L.; Čižmár, Erik; Feher, Alexander; Babkin, Roman Yu.Precipitation of nanocrystallites of cobalt–aluminium layered double hydroxides in a magnetic field has been studied. In a magnetic field perpendicular to the substrate, dense and homogeneous films have been obtained. Magnetic anisotropy of the crystallites is explained by deviation from the statistical cation distribution in favour of honeycomb-like coordination of cobalt.
Dielectric and infrared spectroscopy characterization of Co–Al layered double h...
Zamaraite, Ilona; Vieira, Daniel E. L.; Vieira, Luís G.; Ribeiro, José L.; Vieira, Joaquim M.; Salak, Andrei N.; Banys, JūrasLayered double hydroxides (LDHs) are natural 2D materials with promising functionalities. A comprehensive understanding of physical properties (such as electrical or optical) is critical for their current and future applications. Herein, dielectric and infrared spectroscopy to extensively characterize thermal behavior of dynamic effects in cobalt–aluminum LDH with Co-to-Al ratio of 2 and intercalated with nitra...
Interplay of magnetic properties and doping in epitaxial films of h-REFeO3 mult...
Baghizadeh, Ali; Vaghefi, Pegah Mirzadeh; Huang, Xing; Borme, Jerome; Almeida, Bernardo; Salak, Andrei N.; Willinger, Marc-Georg; Amaral, Vitor B.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 rea...
Comparative optic studies of cobalt-based layered double hydroxides with nitrat...
Pashkevich, Yurii; Gnezdiov, Vladimir; Vieira, Daniel E. L.; Babkin, Roman; Lukienko, Irina; Vieira, Joaquim M.; Wulferding, Dirk; Lemmens, PeterThe variations of Raman and optic absorption spectra of Co-Al layered double hydroxides (LDH) intercalated with nitrate and carbonate anions have been studied as a function of the Co2+/Al3+ ratio. It was revealed from the comparative analysis of the hydrogen bond frequencies in Raman spectra and the phonon repetition lines in optic absorption spectra that the increasing Co2+/Al3+ ratio results in an enhancement...
Magnetic behaviour of perovskite compositions derived from BiFeO3
Salak, Andrei N.; Cardoso, João Pedro V.; Vieira, Joaquim M.; Shvartsman, Vladimir V.; Khalyavin, Dmitry D.; Fertman, Elena L.; Fedorchenko, Alexey V.The phase content and sequence, the crystal structure, and the magnetic properties of perovskite solid solutions of the (1−y)BiFeO3–yBiZn0.5Ti0.5O3 series (0.05 ≤ y ≤ 0.90) synthesized under high pressure have been studied. Two perovskite phases, namely the rhombohedral R3c and the tetragonal P4mm, which correspond to the structural types of the end members, BiFeO3 and BiZn0.5Ti0.5O3, respectively, were reveale...
Phase transitions in the metastable perovskite multiferroics BiCrO3 and BiCr0.9...
Cardoso, João Pedro; Delmonte, Davide; Gilioli, Edmondo; Fertman, Elena L.; Fedorchenko, Alexey V.; Shvartsman, Vladimir V.; Paukšta, VaidotasThe temperature behavior of the crystal structure as well as dielectric and magnetic properties of the perovskite bismuth chromate ceramics with the 10 mol % Cr3+-to-Sc3+ substitution were studied and compared with those of the unmodified compound. Using a high-pressure synthesis, BiCrO3 and BiCr0.9Sc0.1O3 were obtained as metastable perovskite phases which are monoclinic C2/c with the √6ap × √2ap × √6ap supers...