On the True Photoreactivity Order of 001, 010, and 101 Facets of Anatase TiO2 Crystals

Contrary to conventional understanding, clean anatase 001 facets exhibit lower photoreactivity than 101 facets. Furthermore, the 010 facets showed the highest photocatalytic reactivity in generating OH radicals and hydrogen evolution. This behavior was revealed by studies on crystals grown hydrothermally to have a predominance of 001, 101, or 010 facets (left to right in picture (a) and (b) – (d), respectively).