Well‐Defined Non‐spherical Copper Sulfide Mesocages with Single‐Crystalline Shells by Shape‐Controlled Cu2O Crystal Templating

The ability to synthetically tune the structure, size, and shape of inorganic materials is an important goal in current material synthesis and device fabrication at the mesoscale. Micro-and nanostructures with hollow interiors have aroused intense interest in recent years, mainly owing to their potential applications in photonic crystals, catalysis, drug delivery, artificial cells, lightweight fillers, and the protection of light-sensitive components. [1–7] A variety of methods have been developed to generate hollow structures of inorganic materials. [8–20] Among them, template-directed synthesis has been demonstrated to be an effective approach in which hard templates, such as polystyrene latex spheres, [8,9] colloidal particles, [10,11] and carbon spheres, [12] and soft templates, such as gas bubbles, [13] emulsion droplets, [14–16] and micelles, [17] are employed. However, in most cases, the hollow structures obtained are spherical, polycrystalline shells. Recently, some progress has been made on the synthesis of hollow non-spherical structures with poly-[20,21] or single-crystalline [22–24] shells. For example, single-crystalline shells of cubic AuAg alloy nanoboxes can be synthesized by a replacement reaction using silver nanocubes as templates. [21] PbTe alloy nanoboxes can be fabricated by a solvothermal route. [23] Moreover, single-crystalline octahedral Cu 2 O nanocages are produced in solu-tion by the catalytic reduction of a copper tartrate complex. [24] However, the controllable synthesis of single-crystalline hollow mesostructures of other inorganic materials with well-defined non-spherical morphologies is still much needed. Transition metal sulfides have excellent