One-Step Synthesis of Submicrometer Fibers of MoO₃

Nanorods of MoO 3 are accessible in gram quantities from MoO 3 ·2H 2 O via a flexible one-step solvothermal reaction. Several hours of treatment in water at 180 °C are sufficient to convert the starting material quantitatively into rods with diameters around 100 nm and microscale lengths. The formation of MoO 3 rods proceeds in both neutral ionic and acidic media within a wide parameter window encompassing reaction temperatures between 90 and 180 °C and time scales ranging from several hours to 7 d. The rod morphology can be tuned by selecting a proper additive, and the nanorods withstand heating to 400 °C. Furthermore, the reaction pathways in various solvothermal media were investigated and both intermediate molybdic acids and the bulk nanorod products were characterized by means of EXAFS spectroscopy.