Vol.:(0123456789) 1 3 Journal of Materials Science: Materials in Electronics https://doi.org/10.1007/s10854-018-9590-2 Structural and dielectric behaviour analysis of TiO 2 addition on the ceramic matrix BiVO 4 R. G. M. Oliveira 1,2,5  · G. S. Batista 1,2,5  · J. E. V. de Morais 1,2,5  · M. M. Costa 3  · M. A. S. Silva 2,5  · J. W. O. Bezerra 1,2,5  · A. S. B. Sombra 1,2,4,5 Received: 15 December 2017 / Accepted: 2 July 2018 © Springer Science+Business Media, LLC, part of Springer Nature 2018 Abstract In this work, the dielectric and electric properties of the ceramic matrix BiVO 4 (BVO) and the efects of the addition of TiO 2 were analysed by impedance spectroscopy (IS). The BVO phase was calcined at 773 K and used to prepare the composite ceramic which the titanium oxide was added (15, 30 and 60 wt% TiO 2 ), molded in pellet shape and sintered at 1073 K. These samples were characterized by X-ray difraction (XRD). The thermo-activated charge transfer process for the ceramics BVO with the respective additions was observed and the electric results were compared with the electric response of equivalent circuit composed of three associations in parallel with R-CPE and represented by the Nyquist diagram. At room temperature and in the frequency range of 1 Hz, the samples presented high relative permittivity, ε r = 26k to approximately 35k, and a dielectric loss at the order of 10 −2 at 1 MHz. The composites presented negative and positive values of the temperature coefcient of capacitance (TCC) along TiO 2 composition. Through IS coupled with temperature variation, the activation energies were measured; the values showed decrease with increasing withTiO2 concentration. 1 Introduction Four diferent crystallographic phases of bismuth vanadate (BiVO 4 ) are reported in the literature. Its orthorhombic phase occurs naturally; the phases synthesized in labora- tory consist of tetragonal zircon, monoclinic scheelite (group of space I2/b) and tetragonal scheelite. It was reported that tetragonal BiVO 4 (BVO) with a 2.9 eV band gap mainly possesses a UV absorption band, while monoclinic BVO with a 2.4 eV band gap has a characteristic visible light absorption band besides the UV band [1]. (BVO) is widely studied for its use in photocatalysis, high-temperature con- ductors, dielectrics, and it is also commercially available as a high-performance pigment in the coatings and plastics industries [1–6]. Monoclinic phases from vanadates are obtained from aqueous process at room temperature [7] and by a solid- state reaction at 873 K [1]. This monoclinic phase is noted for its photocatalytic activities [8, 9] and good response to visible light [8–10]. * R. G. M. Oliveira ronaldomaia@fsica.ufc.br * A. S. B. Sombra asbsombra@gmail.com G. S. Batista graciliano@fsica.ufc.br J. E. V. de Morais eduardovasconc@gmail.com M. M. Costa maurocosta48@gmail.com M. A. S. Silva marceloassilva@yahoo.com.br J. W. O. Bezerra wagner.bezerra@gmail.com 1 Telecommunication Engineering Department, Federal University of Ceará (UFC), P.O. Box 6007, Fortaleza, Ceará 60755-640, Brazil 2 LOCEM-Telecommunication and Materials Science and Engineering of Laboratory (LOCEM), Physics Department, Federal University of Ceará (UFC), P. O. Box 6030, Campus PICI, Fortaleza, Ceará 60455-760, Brazil 3 Institute of Physics, LACANM, UFMT, Cuiabá, MT 78060-900, Brazil 4 Laboratorio de Redes de Comunicação e Segurança (LARCES), Universidade Estadual do Ceará, Campus do Itaperi, Av. Paranjana 1700, Fortaleza, Ceará 60755-640, Brazil 5 https://www.locem.ufc.br