Síntese e formação de nanoestruturas e filmes de alumina anódica porosa
Resumen
This paper presents a methodology for obtaining the porous anodic
alumina. anodization of aluminum in acidic electrolytes may specifically result in
different types of oxide films as a barrier type porous type. Anodic alumina is
formed with a regular porous structure on the nanometer scale when using the
technique of two-step anodizing in galvanostatic mode, where the applied
current density is fixed and observing the variation of potential along the way. In
this study, we used a factorial design to investigate the effects of variables on
morphology and electrochemical responses, the planning matrix allowed
mapping the proposed system, and the influence of the variables chosen in
three different responses from electrochemical anodization curves. For this
study three experimental parameters were chosen, as follows: temperature,
electrolyte concentration and current density, all varying in two levels. The
electrochemical response parameters chosen were: slope of the curve, the
maximum potential and steady potential. These electrochemical responses
provide information about the mechanism and kinetics of growth of oxide films,
being important in the verification of some properties of the final preparation. As
a result , and based on Pareto charts , it can be seen that the current density is
the parameter most affected by the slope of the curve is related to the rate of
growth of the oxide barrier formed initially. On the other hand , the maximum
potential, early processes related to the source and opening pore was observed
that the three variables influencing this response. Finally, the stationary
potential important parameter related to the dissolution rate and the formation of
porous oxide in dynamic equilibrium noted that all three variables were
significant in the process. This study enabled to view the influence of
independent variables and their cross- tillage on the growth of anodic alumina
film .Os PLA films were characterized morphologically interactions to verify the
homogeneity of the structures and relationships of the variables in the pore
radius of AAP .