Interfacial Reaction‐Directed Synthesis of Ce–Mn Binary Oxide Nanotubes and Their Applications in CO Oxidation and Water Treatment

Interfacial oxidation–reduction reaction is herein developed to prepare hollow binary oxide nanostructures. Ce–Mn nanotubes are fabricated by treating Ce(OH)CO₃ templates with KMnO₄ aqueous solution, where MnO₄^? is reduced to manganese oxide and the Ce³⁺ in Ce(OH)CO₃ is simultaneously oxidized to form cerium oxide, followed by selective wash with HNO₃. The resulting Ce–Mn binary oxide nanotubes exhibit high catalytic activity towards CO oxidation and show significant adsorption capacity of Congo red. Moreover, guided by the same interfacial‐reaction principle, binary oxide hollow nanostructures with different shapes and compositions are synthesized. Specifically, hollow Ce–Mn binary oxide cubes, and Co‐Mn and Ce‐Fe binary oxide hollow nanostructures are achieved by changing the shape of the Ce(OH)CO₃ templates from rods to cubes, by changing the tempates from Ce(OH)CO₃ nanorods to Co(CO₃)_0.35Cl_0.20(OH)_1.10 nanowires, and by replacing the oxidant of KMnO₄ with another strong one, K₂FeO₄, respectively. This work is expected to open a new, simple avenue for the general synthesis of hollow binary oxide nanostructures.