Molybdenum trioxide, or MoO3, is a chemical compound made up of molybdenum and oxygen. It appears as a white or yellowish powder and is commonly used in various industrial applications, including catalysts, pigments, and as a precursor for other molybdenum compounds. MoO3 is also important in the production of high-performance alloys and in the glass industry, where it can enhance the properties of glass products. Additionally, it plays a role in electronics, particularly in the fabrication of thin films for semiconductors.