alpha-MoO3 thin sheets were successfully synthesized from all commercial materials using a fast, effective and simple method and characterized by X-ray diffractometer, scanning electron microscopy, IR and Raman spectroscopy. The prepared catalyst was highly active and selective to formaldehyde formation from methanol over a wide range of reaction temperatures comparing to the commercial one. We found that the high selectivity of formaldehyde over the prepared alpha-MoO3 was originated from its special morphology, which had abundant exposed edges comparing to the commercial alpha-MoO3. Additionally, the prepared alpha-MoO3 showed significant stability due to its stable nature. [GRAPHICS]