A facile top-down etching to create a Cu2O jagged polyhedron covered with numerous {110} edges and {111} corners with enhanced photocatalytic activity.

Cutting edge: A Cu(2)O jagged polyhedron, with numerous {110} edges and {111} corners, has been developed through a top-down selective oxidative etching process at the expense of the original {111} facet (see figure). The as-prepared nanocrystals exhibited higher photocatalytic activities for the degradation of methylene orange, which may be primarily ascribed to the increased edges and corners.