Morphology-controlled synthesis of α-MoO3 nanomaterials for ethanol oxidation

α-MoO3 nanobelts of about 8 nm in thickness, 60 nm in width and 0.7–7.5 μm in length were synthesized through a hydrothermal process. It was found that the pH value and the concentration of the surfactant (P123) played crucial roles in determining the crystal phase and the shape of the MoO3 nanomaterials. Small-sized nanobelts were produced at a lower pH value and a suitable P123 concentration in the synthetic solution. Further increase in the surfactant concentration directed self-assembly of the nanobelts into hierarchical microflowers. The α-MoO3 nanobelts showed a relatively higher activity but a lower selectivity toward acetaldehyde in ethanol oxidation than the microflowers, primarily due to the large exposure of the (010) planes.