This work is intended to define an optimal methodology of preparation of highly ordered TiO2 nanotube arrays by a 60 V anodization in a glycol ethylene solution. In the order to obtain a mechanically stable structure with an high UV photoconversion efficiency is necessary to mantain a careful control of the growth mechanism by anodization process. For this reason, the nanotube arrays has to be formed upon a compact and well-defined thickness titanium dioxide layer. Besides, both fluoride concentration and anodization time are strictly correlated, because too elevated concentrations and/or a long anodization time produce instable structure with low photoconversion efficiency. The best result in the terms of reproducibility has been obtained previously operating a 3 min. galvanostatic oxide growth on the pickled titanium sheet, and anodic growth in ethylene glycol solution containing 1% wt. H2O and 0,20% wt. NH4F for a time lower than 4.5 hours. The UV photoconversion efficiency was measured and a maximum value of 28.3% has been obtained, which is the highest result in the literature.
Stable TiO2 nanotube arrays with high UV photo-conversion efficiency / Pasquali, Mauro; Pozio, A; Mura, Francesco; Masci, A.. - (2009). (Intervento presentato al convegno HYSYDAYS – 3rd WORLD CONGRESS OF YOUNG SCIENTISTS ON HYDROGEN ENERGY SYSTEMS tenutosi a Torino nel 7-9 ottobre 2009).
Stable TiO2 nanotube arrays with high UV photo-conversion efficiency
PASQUALI, Mauro;MURA, FRANCESCO;
2009
Abstract
This work is intended to define an optimal methodology of preparation of highly ordered TiO2 nanotube arrays by a 60 V anodization in a glycol ethylene solution. In the order to obtain a mechanically stable structure with an high UV photoconversion efficiency is necessary to mantain a careful control of the growth mechanism by anodization process. For this reason, the nanotube arrays has to be formed upon a compact and well-defined thickness titanium dioxide layer. Besides, both fluoride concentration and anodization time are strictly correlated, because too elevated concentrations and/or a long anodization time produce instable structure with low photoconversion efficiency. The best result in the terms of reproducibility has been obtained previously operating a 3 min. galvanostatic oxide growth on the pickled titanium sheet, and anodic growth in ethylene glycol solution containing 1% wt. H2O and 0,20% wt. NH4F for a time lower than 4.5 hours. The UV photoconversion efficiency was measured and a maximum value of 28.3% has been obtained, which is the highest result in the literature.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
