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Previous issue date: 2012-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The field of "Materials Chemistry" has been developing in recent years and there has
been a great increase of interest in the synthesis and chemical and physical properties of
new inorganic solids. New routes of synthesis and synthesis modified has been
developed with the aim not only to optimize the processes in laboratory scale, but also
on an industrial scale, and make them acceptable by current environmental legislation.
The phenomenology of current solid state chemistry properties coupled with the high
temperature superconductivity, ferromagnetism, porosity molecular and colors are
evidence affected by the synthesis method, which in turn can influence the
technological application of these materials. From this understanding, mixed oxides of
nickel and zinc nanoparticulate were synthesized by microwave-assisted combustion
route using three specific types of organic fuels employing the weight ratios 1:1/2 and
1:1 of cation metallic/fuel, in order to investigate the influence of such proportions to
obtain the solids. The new fuels were chosen to replace, for example, urea or glycine
that are the fuels most commonly preferred in this kind of synthesis. The powders
without heat treatment were studied by Thermogravimetric analysis (TGA), X-Ray
Diffraction (XRD) and then calcined at 900?C. After heat treatment, the samples were
characterized by analysis of X Ray Diffraction (XRD) and Scanning Electron
Microscopy (SEM). The modified synthesis route porposed was effective for obtaining
powders. Both the alternative fuels chosen as the different weight ratios employed,
influenced in the morphology and obtaining oxides / O campo da Qu?mica de Materiais vem se desenvolvendo nos ?ltimos anos, tendo
havido um grande aumento do interesse na s?ntese e nas propriedades qu?micas e f?sicas
de novos s?lidos inorg?nicos. Novas rotas de s?nteses e s?nteses modificadas tem sido
desenvolvidas com o intuito n?o apenas de otimizar os processos em escala
laboratorial, como tamb?m em escala industrial, al?m de torn?-los aceit?veis pela
legisla??o ambiental vigente. A atual fenomelogia da qu?mica do estado s?lido aliada ?s
propriedades de supercondutividade ? alta temperatura, ferromagnetismo, porosidade
molecular e cores s?o evid?ncias afetadas pelo m?todo de s?ntese, que por sua vez,
podem influenciar na aplica??o tecnol?gica desses materiais. Foi a partir desta
compreens?o, que ?xidos mistos de n?quel e zinco nanoparticulados foram sintetizados
atrav?s da rota combust?o por microondas utilizando tr?s tipos espec?ficos de
combust?veis e empregando as raz?es m?ssicas 1:1 e 1:1/2 de c?tions
met?licos/combust?vel, com o intuito de averiguar a influ?ncia de tais propor??es na
obten??o dos s?lidos. Os novos combust?veis foram escolhidos em substitui??o a ur?ia
ou glicina que s?o mais comumente preferidos nesse tipo de s?ntese. Os p?s sem
tratamento t?rmico foram estudados atrav?s da An?lise Termogravim?trica (ATG) e da
Difra??o de Raios-X (DRX), sendo, em seguida, submetidos ao tratamento t?rmico ?
900?C. Ap?s as calcina??es, foram caracterizados atrav?s das an?lises Difra??o de raiosx
(DRX) e Microscopia Eletr?nica de Varredura (MEV). A rota de s?ntese modificada
foi eficaz para obten??o dos p?s. Tanto os combust?veis alternativos escolhidos quanto
as diferentes raz?es m?ssicas empregadas, influenciaram na morfologia e na obten??o
dos ?xidos
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/12775 |
| Date | 31 August 2012 |
| Creators | Silva, Rayssa Rafaelli Nunes Melo da |
| Contributors | CPF:06117988320, http://lattes.cnpq.br/3318871716111536, Paskocimas, Carlos Alberto, CPF:06296687877, http://lattes.cnpq.br/2365059843175411, Vitor Sobrinho, Eledir, CPF:64656969915, http://lattes.cnpq.br/8488499388852606, Barros, Joana Maria de Farias, CPF:85239658404, http://lattes.cnpq.br/1016070459137884, Melo, Dulce Maria de Ara?jo |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Ci?ncia e Engenharia de Materiais, UFRN, BR, Processamento de Materiais a partir do P?; Pol?meros e Comp?sitos; Processamento de Materiais a part |
| 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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