Nesta dissertação estudou-se a influência dos parâmetros de pós-tratamento eletroquímico, em condições potenciodinâmicas, sobre a estabilidade e reatividade frente à organofosfatos do filme eletrodepositado de hexacianoferrato (II) de ferro (III), mais conhecido como azul da Prússia (PB). O pós-tratamento do filme em baixas velocidades de varredura leva à formação do PB \"solúvel\" com a formação de grãos maiores e um filme mais estável eletroquimicamente como demonstrado por ensaios de voltametria cíclica (VC), microscopia de força atômica (AFM) e espectroscopia de fotoelétrons excitados por raios X (XPS). Filmes pós-tratados em meio HCl/KCl 0,1M foram mais eletroquimicamente estáveis em meio ácido, enquanto filmes submetidos à pós-tratamento em meio neutro foram mais estáveis em meio neutro. / In this work it was studied the influence of the electrochemical posttreatment parameters in potenciodinamics conditions on the stability and reactivity against organophosphates by eletrodepositaded iron (III) hexacyanoferrate (II), better known as blue of Prussia (PB). The posttreatment of the film at low sweep rates leads to the formation of the PB \"soluble\" with the formation of larger grains and a more electrochemically stable films as demonstrated by cyclic voltammetry (VC), atomic force microscope (AFM) and X-ray photoelectron espectroscopic (XPS) tests. Films post-treated in HCl/KCl 0.1 M media were more electrochemically stable in an acid media, while films submitted to post-treatment in neutral media were more stable in neutral media.

The hydrothermal and solid state methods were used in the synthesis of some aluminoborophosphate compounds. The products were investigated by using XRD, IR, DTA, DSC, ICP and SEM methods. The solid state reactions have been studied in the range 700 &ndash / 1200&amp / #61616 / C. Using several hydrothermal methods a novel aluminum phosphate compound Al3-xBxP3O12 was synthesized. The crystal system was found to be tetragonal with a=17.1629 and c = 12.6084A&deg / unit cell parameters and space group is P4212 (No:90). In anorthite mineral (CaAl2Si2O8) by replacing two silicon with boron and phosphorus, a boron containing anorthite with the formula of CaAl2BPO8 was prepared. The indexed data was reported for the first time in this thesis. Its crystal system was found to be monoclinic with the following unit cell parameters and &amp / #946 / angle / a=10.0440&Aring / , b = 12.6587 &Aring / , c = 14.4332 &Aring / and &amp / #946 / = 91.55&deg / . In this study, AlPO4.xH2O was also obtained by a hydrothermal method while trying to synthesize AlBP4O13. All the prepared compounds have been investigated by IR spectroscopy and the assignment of the functional B-O and P-O groups were done.

Nesta dissertação estudou-se a influência dos parâmetros de pós-tratamento eletroquímico, em condições potenciodinâmicas, sobre a estabilidade e reatividade frente à organofosfatos do filme eletrodepositado de hexacianoferrato (II) de ferro (III), mais conhecido como azul da Prússia (PB). O pós-tratamento do filme em baixas velocidades de varredura leva à formação do PB \"solúvel\" com a formação de grãos maiores e um filme mais estável eletroquimicamente como demonstrado por ensaios de voltametria cíclica (VC), microscopia de força atômica (AFM) e espectroscopia de fotoelétrons excitados por raios X (XPS). Filmes pós-tratados em meio HCl/KCl 0,1M foram mais eletroquimicamente estáveis em meio ácido, enquanto filmes submetidos à pós-tratamento em meio neutro foram mais estáveis em meio neutro. / In this work it was studied the influence of the electrochemical posttreatment parameters in potenciodinamics conditions on the stability and reactivity against organophosphates by eletrodepositaded iron (III) hexacyanoferrate (II), better known as blue of Prussia (PB). The posttreatment of the film at low sweep rates leads to the formation of the PB \"soluble\" with the formation of larger grains and a more electrochemically stable films as demonstrated by cyclic voltammetry (VC), atomic force microscope (AFM) and X-ray photoelectron espectroscopic (XPS) tests. Films post-treated in HCl/KCl 0.1 M media were more electrochemically stable in an acid media, while films submitted to post-treatment in neutral media were more stable in neutral media.