Properties characterization of Ce(DPM)4 served as precursor for MOCVD

High purity Ce(DPM)4 (DPM=2,2,6,6-tetramethyl-3,5-heptanedionato) powder was successfully synthesized from Ce(NO)3 and HDPM followed by reduced pressure distillation and recrystallization from toluene. This metal β-diketonate complex used as precursor for metal–organic chemical vapor deposition (MOCVD) of CeO2 film has been characterized by elemental analyses, X-ray diffraction (XRD), thermogravimetry–differential thermal analysis (TG–DTA) analysis, 1H-NMR spectroscopy, and infrared spectroscopy. The structure of this complex is monocline and the sublimation temperature is 145°C. This product was sufficiently stable after it was exposed to air for 30 days, as only a few impurities such as Ce2(CO3)3·8H2O, Ce(OH)3, and H2O can be identified. Ce(DPM)4 decomposes during evaporation, the chemical bonds dissociate in the sequence of CC(CH3)3>CH>CO and CC by heating. At 280°C this complex thoroughly decomposes to CeO2.