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Previous issue date: 2013-07-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / A new self-sustainable film was prepared through the sol-gel modified method,
previously employed in our research group; sodium alginate was used as the polymer
matrix, along with plasticizer glycerol, doped with titanium dioxide (TiO2) and tungsten
trioxide (WO3). By varying WO3 concentration (0,8, 1,6, 2,4 and 3,2 μmol) and keeping
TiO2 concentration constant (059 mmol), it was possible to study the contribution of these
oxides on the obtained films morphological and electrical properties. Self-sustainable
films have analyzed by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray
Diffraction (XDR), Scanning Electron Microscope (SEM), Energy Dispersive X-ray
Spectroscopy (EDS) and Electrochemical Impedance Spectroscopy (EIS). By the IR
specters, it was possible identify the TiO2, and posteriorly WO3, addition has provided
dislocation of alginate characteristics bands to smaller vibrations frequencies indicating
an electrostatic interaction between the oxides and the polymer matrix. Diffractograms
show predominance of the amorphous phase in the films. SEM, along with EDX, analysis
revealed self-sustainable films showed surface with no cracks and relative dispersion of
the oxides throughout the polymer matrix. From Impedance analysis, it was observe
increasing WO3 concentration to 2,4 μmol provided a reduction of films resistive
properties and consequent improvement of conductive properties / Um novo filme autossustent?vel foi preparado, atrav?s do m?todo sol-gel modificado,
anteriormente empregado no nosso grupo de pesquisa, utilizando como matriz polim?rica
o alginato de s?dio, juntamente com o plastificante glicerol, dopado com di?xido de
tit?nio (TiO2) e tri?xido de tungst?nio (WO3). Variando as concentra??es do WO3 (0,8,
1,6, 2,4 e 3,2 μmol), e mantendo constante a concentra??o do TiO2 (0,59 mmol), foi
poss?vel estudar a contribui??o destes ?xidos nas propriedades morfol?gicas e el?tricas
dos filmes obtidos. Os filmes autossustent?veis foram caracterizados atrav?s das t?cnicas
de Espectroscopia de Infravermelho com Transformada de Fourier (FTIR), Difratometria
de Raios X (DRX), Microscopia Eletr?nica de Varredura (MEV), Espectroscopia de
Raios X por Dispers?o de Energia (EDS) e Espectroscopia de Imped?ncia Eletroqu?mica
(EIE). Atrav?s dos espectros de FTIR foi poss?vel identificar que a adi??o do TiO2 e,
posteriormente, do WO3 proporciona deslocamento das bandas caracter?sticas do alginato
para menores frequ?ncias de vibra??o, indicando uma intera??o eletrost?tica dos ?xidos
com a matriz polim?rica. Os difratogramas evidenciaram a predomin?ncia do
comportamento amorfo nos filmes. As an?lises de MEV, juntamente com as de EDS,
revelaram que os filmes autossustent?veis apresentam uma superf?cie sem trincamento e
de relativa dispers?o dos ?xidos ao longo da matriz polim?rica. Atrav?s da EIE observouse
que o aumento da concentra??o de WO3 at? 2,4 μmol proporcionou uma redu??o do
comportamento resistivo dos filmes, e consequente melhoria em suas propriedades
condutoras
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17739 |
| Date | 30 July 2013 |
| Creators | Morais, William Gomes de |
| Contributors | CPF:10843329491, http://lattes.cnpq.br/2069510469317474, Huitle, Carlos Alberto Martinez, CPF:01139059980, http://lattes.cnpq.br/2485073932883264, Fonseca, Jos? Luis Cardozo, CPF:90623207753, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4788562T6, Costa, Jos? Alzamir Pereira da, CPF:16357671720, http://lattes.cnpq.br/5592146590288686, Cavalcante, Maria Gorette |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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