Synthesis, characterization, and thermostability of bis(2,2,6,6- tetramethyl-3,5-heptanedionato)copper(II)

Owing to the adaptability to large scale processing, excellent composition control and film uniformity, the metal-organic chemical vapor deposition (MOCVD) technique is a promising process for high-temperature superconductor YBa ₂Cu ₃O _7-δ(YBCO) preparation. In this technique, the evaporation characteristics and thermostability of adopted precursors in whole process will decide the quality and reproducible results of YBCO film. In the present report, bis(2,2,6,6-tetramethyl-3,5-heptanedionato) copper(II) (Cu(TMHD) ₂) was synthesized by the interaction of copper acetate hydrate with TMHD in methanol solution, and its structure was identified by FTIR, ¹H NMR, and EI-MS spectroscopy. Subsequently, thermal property and the kinetics of decomposition were systematically investigated by nonisothermal thermogravimetric analysis methods (TGA) at different heating rates in streams of N2, and the average apparent activation energy of evaporation process was evaluated by the Ozawa, Kissinger, and Friedman methods. The possible conversion function was estimated through the Coats-Redfern method to characterize the evaporation patterns and followed a phase boundary reaction mechanism by the contracting area equation with average activation energy of 85.1 kJ·mol ^-1.