Abstract
The shape of Ag 2 O crystals that evolve from edge and corner-truncated cubes into rhombicuboctahedrons, then to hexapods can be conducted precisely by simply controlling the amount of AgNO 3 , NH 4 NO 3 and NaOH precursors. The edge and corner-truncated cube crystals possess the highest photocatalytic activity, followed by the rhombicuboctahedrons, then the hexapods. The photocatalytic activity of the Ag 2 O crystals depends greatly on the type of the exposed facets. The {10 0} facets exhibit the highest photocatalytic activity in methyl orange solution under full-spectrum light irradiation, followed by the {11 0} facets, then the {111} facets. The {1 0 0} facets are also demonstrated to show intense susceptibility toward etching by NH 3 .