Direct synthesis of LiN thin layer on lithium target surface for BNCT in N gaseous conditions

Ishiyama, Shintaro; Baba, Yuji  ; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*

To prevent vaporization damage of BNCT (Boron Neutron Capture Therapy) lithium target during operation, direct synthesis of LiN thin layer on lithium target surface was demonstrated in 0.1 MPa N gas at temperature below 548 K and the following conclusions were derived; (1) Synthesis of LiN thin layer on lithium surface was confirmed after nitridation at 276548 K with surface contamination by oxygen and carbon. (2) Rapid nitridation over 1-5wt.%/min was observed above Li melting temperature, whereas slow reaction under 0.02-0.5 wt.%/min below melting temperature. (3) During nitridation, removal of oxygen contamination on LiN thin layer is taken place by nitrogen below Li melting temperature.