Nb₂O₅ Nanorod Bundles for Photocatalytic Ethylene Oxidation

Hierarchical metal oxide superstructures have been widely utilized in various applications, but complex template-assisted procedures and organic structure-directing agents are usually required during synthesis. Herein, a three-dimensional (3D) bundle-like Nb2O5 superstructure was fabricated by a simple hydrothermal method using amorphous Nb2O5·nH2O particles as precursors without the use of organic species and template precursors. Controlled experiments under different synthetic conditions revealed that a hierarchical assembly process occurred, in which Nb2O5 nanorods were first formed due to the dissolution and recrystallization of Nb2O5·nH2O particles. The resultant nanorods were assembled into bundle-like nanostructures, which finally organized into flower-like superstructures. Upon decorating of ultrafine Pt nanoparticles (1.8 nm) on the surface of Nb2O5–S using a photodeposition method, the Pt–Nb2O5 superstructures showed promising photoactivities for ethylene oxidation.