Innovating pulsed electrophoretic deposition of boehmite nanoparticles dispersed in an aqueous solution, into a model porous anodic film, prepared on aluminium alloy 1050

Abstract

International audienceThe present study investigates the pulsed electrophoretic deposition of boehmite particles, previously dispersed in an aqueous solution, into the pores of a model anodic film, prepared using phosphoric acid electrolyte, on an aluminium alloy 1050 (AA1050) substrate. Particles were successfully inserted into the pores, despite some limitations resulting both from the barrier layer, which transpired to be semi-conducting, and from water electrolysis. To address this issue, a pulsed electric field, set to above a threshold value, allowed a current to be sent through the cell, this being accompanied by a reduction of water electrolysis; insertion of particles thus became possible. Scanning Electron Microscope (FEG-SEM) observations, X-Ray Diffraction (XRD) spectroscopy and Electrochemical Impedance Spectroscopy (EIS) studies gave some clues as to the reality of particle impregnation into the pores. Furthermore, an improvement in the porous anodic film filling was achieved using hydrothermal post-treatmen

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