Facet-dependent photocatalytic activity and facet-selective etching of silver(I) oxide crystals with controlled morphology

Abstract

The shape of Ag2O crystals that evolve from edge and corner-truncated cubes into rhombicuboctahedrons, then to hexapods can be conducted precisely by simply controlling the amount of AgNO3, NH4NO3 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 Ag2O 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 NH3.