One-Step Synthesis of Submicrometer Fibers of MoO3

Nanorods of MoO3 are accessible in gram quantities from MoO3·2H2O 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 MoO3 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.