Spinous TiO2 and Au@TiO2 octahedral nanocages: Amorphisity-to-crystallinity transition-driven surface structural construction and photocatalytic study

Novel spinous TiO2 and Au@TiO2 octahedral nanocages have been prepared through a well-designed three-step strategy including templated TiO2 wet coating, subsequent structural ripening and final template removal or transformation. The strategy is built on an amorphisity-to-crystallinity transition-driven surface structural construction, which emphasizes the critical steps of crystallization-controlled TiO2 coating and consequent structural ripening. The influence of some key parameters, such as coating temperature, ripening temperature and ripening time, on the structure and morphology of the spinous TiO2 and Au@TiO2 nanocages have been investigated. In addition, in photocatalytic measurements, the prepared spinous TiO2-based nanocages exhibit enhanced photocatalytic efficiency relative to spinousless TiO2-based nanocages as well as P-25, owing to their structure advantages resulting from spinous surfaces. The photocatalytic activity of these TiO2 based photocatalysts has been systematically studied through the corresponding (OH)-O-center dot radical measurements. The synthetic strategy may work as a general method, through similarly designing, to realize surface structure engineering for various materials such as metals, hydroxide and other oxides besides TiO2. (C) 2014 Elsevier Inc. All rights reserved.