A composite coating of GO-Al2O3 for tritium permeation barrier

To improve tritium permeation resistance and toughness of Al2O3 coating, a new graphene oxide (GO)-alumina (Al2O3) composite coating as tritium permeation barrier was designed in this paper. GO was added into Al2O3 to prepare the composite coating of GO-Al2O3 by a sol-gel method. The results showed that the deuterium permeation reduction factor (PRF) of 0.5 wt% GO-Al2O3 coating was higher than that of the pure Al2O3 coating at 500 degrees C. It was related to the GO nanosheets blocking the diffusion of deuterium atoms in the Al2O3 coating and reducing the permeability. Meanwhile, the toughness of the 0.5 wt% GO-Al2O3 coating was enhanced by about 40 % than the pure Al2O3 coating. The reason can be speculated that GO nanosheets can prevent the cracks propagation in the composite coating of GO-Al2O3. This study could provide a new material of tritium permeation barrier for fusion reactors.