Synergistic effects of iodine and silver ions co-implanted in 6H–SiC

• Published in: Journal of nuclear materials 2015-12, Vol.467 (Part 2), p.582-587
• Main Authors: Kuhudzai, R.J., Malherbe, J.B., Hlatshwayo, T.T., van der Berg, N.G., Devaraj, A., Zhu, Z., Nandasiri, M.
• Format: Article
• Language: English
• Subjects: Annealing; Coating; Environmental Molecular Sciences Laboratory; Fission products; Iodine; Secondary ion mass spectrometry; Silicon carbide; Silver; Synergistic effect
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2015.10.029

Motivated by the aim of understanding the release of fission products through the SiC coating of fuel kernels in modern high temperature nuclear reactors, a fundamental investigation is conducted to understand the synergistic effects of implanted silver (Ag) and iodine (I) in 6H–SiC. The implantation of the individual species, as well as the co-implantation of 360 keV ions of I and Ag at room temperature in 6H–SiC and their subsequent annealing behaviour has been investigated by Secondary Ion Mass Spectrometry (SIMS), Atom Probe Tomography (APT) and X-ray Photoelectron Spectroscopy (XPS). SIMS and APT measurements indicated the presence of Ag in the co-implanted samples after annealing at 1500 °C for 30 h in sharp contrast to the samples implanted with Ag only. In samples implanted with Ag only, complete loss of the implanted Ag was observed. However, for I only implanted samples, some iodine was retained. APT of annealed co-implanted 6H–SiC showed clear spatial association of Ag and I clusters in SiC, which can be attributed to the observed I assisted retention of Ag after annealing. Such detailed studies will be necessary to identify the fundamental mechanism of fission products migration through SiC coatings. •Co-implantation of Ag and I ions in 6H–SiC was performed.•Clear spatial association of Ag and I clusters observed after annealing.•Complete loss of Ag after high temperature annealing of silver only sample.•Iodine was retained in iodine only sample after high temperature annealing.•Iodine was found to play a role in the retention of Ag in the co-implanted samples.