Vanadium carbide by MOCVD for mitigating the fuel cladding chemical interaction

In this work, a low temperature coating process using an organometallic precursor, vanadocene Cp2V (Cp = C5H5) was developed. An innovative coating setup was built to deposit a uniform vanadium carbide layer. The substrate temperature dependence of coating was investigated with different temperatures at 200 °C, 400 °C and 650 °C. Cross section profile and phase identification showed an average thickness of 4 μm VC coating obtained for the sample prepared at 650 °C. Diffusion couples of HT9/VC/Ce was annealed to a temperature of 660 °C for 100 h and compared to the diffusion behavior of uncoated HT9/Ce. The coated diffusion couple showed a substantial decrease inter-diffusion zone. These preliminary results advocate that VC coatings may be feasible as diffusion barriers against Ce and possibly other lanthanide fission products.