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Silva JPB, Wang J, Koster G, Rijnders G, Negrea RF, Ghica C, Sekhar KC, Moreira JA, Gomes MJM. Hysteretic Characteristics of Pulsed Laser Deposited 0.5Ba(Zr 0.2Ti 0.8)O 3-0.5(Ba 0.7Ca 0.3)TiO 3/ZnO Bilayers. ACS Appl Mater Interfaces 2018; 10:15240-15249. [PMID: 29630331 DOI: 10.1021/acsami.8b01695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In the present work, we study the hysteretic behavior in the electric-field-dependent capacitance and the current characteristics of 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BCZT)/ZnO bilayers deposited on 0.7 wt % Nb-doped (001)-SrTiO3 (Nb:STO) substrates in a metal-ferroelectric-semiconductor (MFS) configuration. The X-ray diffraction measurements show that the BCZT and ZnO layers are highly oriented along the c-axis and have a single perovskite and wurtzite phases, respectively, whereas high-resolution transmission electron microscopy revealed very sharp Nb:STO/BCZT/ZnO interfaces. The capacitance-electric field ( C- E) characteristics of the bilayers exhibit a memory window of 47 kV/cm and a capacitance decrease of 22%, at a negative bias. The later result is explained by the formation of a depletion region in the ZnO layer. Moreover, an unusual resistive switching (RS) behavior is observed in the BCZT films, where the RS ratio can be 500 times enhanced in the BCZT/ZnO bilayers. The RS enhancement can be understood by the barrier potential profile modulation at the depletion region, in the BCZT/ZnO junction, via ferroelectric polarization switching of the BCZT layer. This work builds a bridge between the hysteretic behavior observed either in the C- E and current-electric field characteristics on a MFS structure.
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Affiliation(s)
- J P B Silva
- Centre of Physics , University of Minho , Campus de Gualtar , 4710-057 Braga , Portugal
- IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia , Faculdade de Ciências da Universidade do Porto , Rua do Campo Alegre 687 , 4169-007 Porto , Portugal
| | - J Wang
- Faculty of Science and Technology and MESA+ Institute for Nanotechnology, Inorganic Materials Science , University of Twente , P.O. Box 217, 7500 AE Enschede , The Netherlands
| | - G Koster
- Faculty of Science and Technology and MESA+ Institute for Nanotechnology, Inorganic Materials Science , University of Twente , P.O. Box 217, 7500 AE Enschede , The Netherlands
| | - G Rijnders
- Faculty of Science and Technology and MESA+ Institute for Nanotechnology, Inorganic Materials Science , University of Twente , P.O. Box 217, 7500 AE Enschede , The Netherlands
| | - R F Negrea
- National Institute of Materials Physics , 405A Atomistilor , 077125 Magurele , Romania
| | - C Ghica
- National Institute of Materials Physics , 405A Atomistilor , 077125 Magurele , Romania
| | - K C Sekhar
- Department of Physics, School of Basic and Applied Sciences , Central University of Tamil Nadu , 610101 Thiruvarur , India
| | - J Agostinho Moreira
- IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Departamento de Física e Astronomia , Faculdade de Ciências da Universidade do Porto , Rua do Campo Alegre 687 , 4169-007 Porto , Portugal
| | - M J M Gomes
- Centre of Physics , University of Minho , Campus de Gualtar , 4710-057 Braga , Portugal
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Mihaiescu DE, Cristescu R, Dorcioman G, Popescu CE, Nita C, Socol G, Mihailescu IN, Grumezescu AM, Tamas D, Enculescu M, Negrea RF, Ghica C, Chifiriuc C, Bleotu C, Chrisey DB. Functionalized magnetite silica thin films fabricated by MAPLE with antibiofilm properties. Biofabrication 2012; 5:015007. [PMID: 23254399 DOI: 10.1088/1758-5082/5/1/015007] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We report on the fabrication of magnetite/salicylic acid/silica shell/antibiotics (Fe(3)O(4)/SA/SiO(2)/ATB) thin films by matrix-assisted pulsed laser evaporation (MAPLE) to inert substrates. Fe(3)O(4)-based powder have been synthesized and investigated by XRD and TEM. All thin films were studied by FTIR, SEM and in vitro biological assays using Staphylococcus aureus and Pseudomonas aeruginosa reference strains, as well as eukaryotic HEp-2 cells. The influence of the obtained nanosystems on the microbial biofilm development as well as their biocompatibility has been assessed. For optimum deposition conditions, we obtained uniform adherent films with the composition identical with the raw materials. Fe(3)O(4)/SA/SiO(2)/ATB thin films had an inhibitory activity on the ability of microbial strains to initiate and develop mature biofilms, in a strain- and antibiotic-dependent manner. These magnetite silica thin films are promising candidates for the development of novel materials designed for the inhibition of medical biofilms formed by different pathogenic agents on common substrates, frequently implicated in the etiology of chronic and hard to treat infections.
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Affiliation(s)
- D E Mihaiescu
- Faculty of Applied Chemistry and Materials Science, Politehnica University of Bucharest, 1-7 Polizu Street, Bucharest, Romania
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