Direct Amorphous-structure Analysis: How are Surface/Bulk Structure and Activity of Titania Photocatalyst Particles Changed by Milling?

Changes in surface and bulk structures of rutile titania particles induced by braying up to 10 d and post calcination in air at 773 K were analyzed by reversed double-beam photoacoustic spectroscopy. The observed energy-resolved distribution of electron traps indicated that the surface was amorphized by braying to give rutile-core amorphous-shell structure and the amorphous layer was partly recrystallized by post-calcination leaving grain boundaries in the surface layers, both of which may cause the observed markedly decreased photocatalytic activities.

Automated summary

Analyzing the changes in surface and bulk structures of rutile titania particles induced by braying and post-calcination, it was found that the surface was amorphized and partly recrystallized, leading to decreased photocatalytic activities. This was evidenced by the energy-resolved distribution of electron traps observed using reversed double-beam photoacoustic spectroscopy.