Hafnium(IV) acetylacetonate, with the chemical formula Hf(C5H7O2)4, is a coordination compound where a hafnium(IV) ion is chelated by four acetylacetonate (acac) ligands. It typically appears as a white to off-white crystalline powder and is sensitive to moisture. This compound is primarily utilized as a precursor in materials science. It serves as a key source of hafnium in the chemical vapor deposition (CVD) and atomic layer deposition (ALD) processes for manufacturing high-k dielectric films, such as hafnium oxide (HfO2), which are critical components in advanced semiconductor devices. Additionally, it acts as a catalyst or catalyst precursor in various polymerization reactions, including the ring-opening polymerization of cyclic esters to produce biodegradable polymers like polylactic acid (PLA). Due to its role in electronics manufacturing and polymer synthesis, it is handled as an industrial specialty chemical. Standard safety precautions for metal-organic compounds should be observed, including the use of personal protective equipment and handling under inert atmosphere to prevent decomposition.