Irradiation-induced point defects enhance the electrochemical activity of 3C-SiC: An origin of SiC corrosion

As silicon carbide (SiC) is an inert material, it has attracted attention as an alternative material for the core components of nuclear fuel cladding. However, the corrosion of SiC under neutron irradiation has been reported, and this has been a bottleneck issue. Here, we semi-quantitatively introduced point defects into single crystal 3C-SiC layers by ion irradiation, and investigated their corrosion behavior in terms of the electrochemical activity associated with the point defects. The results showed a shift in corrosion potential and an increase in the corrosion current due to the introduction of defects. However, in the case of aluminum (Al)-doped SiC, these changes were more moderate than in the cases of the nitrogen (N)- or boron (B)-doped material, implying that Al-doped SiC has a better tolerance against corrosion.