Tritium absorption of co-deposited carbon films

Nobuta, Yuji*; Yamauchi, Yuji*; Hino, Tomoaki*; Akamaru, Satoshi*; Hatano, Yuji*; Matsuyama, Masao*; Suzuki, Satoshi; Akiba, Masato

Co-deposited carbon film with different deuterium concentration, D/C, were exposed to tritium gas at the temperature of 423 K, and then the atomic ratio of absorbed tritium to carbon, T/C, was evaluated. The obtained data were discussed with crystal structure of the carbon film. The T/C increased with decreasing D/C of carbon film. The carbon film with low D/C had more defective structure. The reduction of D/C by the heating before tritium exposure led to the increase of absorption amount. These results suggest that carbon film with more defective structure and low D/C film could absorb large amount of tritium. The hydrogen isotope concentration in the present experiment was saturated below the orders of 10, which was 3-4 orders of magnitude smaller than that of co-deposited carbon film with hydrogen isotope.