Advanced oxidation processes for water purification: compact vs nanoporous anodic TiO_2

摘要

The work herein presented is dedicated to a comparison of photodegradation properties of anodic TiO_2 films, involving the study of both oxides with nanotubular geometry and compact layers. The comparison has been performed both through characterization techniques (SEM, XRD) in order to analyze the influence of anodic oxidation parameters on the oxide structures, morphology and crystal structure, and by evaluating photocatalytic degradation of a dye used in textile industry, known as Acid Orange 7 (AO7). Different electrolytes and process parameters were used for the fabrication of both compact oxides and nanotubular layers in order to point out the effect of specific anodic parameters on the photodegradation rate. The characterization of these structures aims to a comparative analysis - between different structures and between similar structures with different features - of photoactivity and related phenomena, which are strongly dependent on the electrolyte used during anodizing, as it influences both morphological features and crystallinity degree.