Template‐Directed Synthesis of Titania Nanocages with Four Tetrahedrally Arranged Open Windows

Original titania nanocages are fabricated from sacrificial silica/polystyrene tetrapod‐like templates. Here the template synthesis, titania deposition and nanocage development through polystyrene dissolution and subsequent silica etching are described. Discussion about the competitive deposition of titania on the biphasic templates is particularly emphasized. The morphology of the nanocages is investigated by TEM, STEM, EDX mapping and electron tomography. Etch‐a‐sketch: Titania nanocages were fabricated by simultaneously carving their hollow core and their four open windows from tetrapod‐like silica/polystyrene templates.