Synthesis of HfC Powders by Carbothermal Reduction of Modified Hafnium Alkoxide Precursors

Abstract

HfC powders were synthesized by carbothermal reduction of modified hafnium alkoxide precursors using hafnium oxychloride, propanol and 2,4-pentanedione as the starting materials. The structure, composition and reaction mechanism of the solution-derived precursor were studied by FT-IR. The forming process of HfC was detected by TG-DSC-FT-IR and XRD, and the formation mechanism was also discussed. The morphology of as-derived HfC powders was observed by SEM. The research showed that the solution-derived precursors of HfC probably had structures of network or chain. Dried precursors showed a honeycomb structure. When pyrolysed, the precursors was firstly converted to HfO2 and amorphous C. HfO2 was deoxidized gradually above 1500 . It seemed that HfC powders were almost pure after heat treatment at 1800 .