A facile approach to fabricate Li4SiO4 ceramic pebbles as tritium breeding materials

• Hydrothermal method was first employed to fabricate the Li4SiO4 ceramic pebbles.
• The Li4SiO4 pebbles with small grain size and abundant pore structure were prepared.
• The Li4SiO4 pebbles have high phase purity and high crush load.

The hydrothermal method was first employed to synthesize the precursor powders for fabricating the Li4SiO4 ceramic pebbles. Compared with the sol–gel method, the precursor powders synthesized by hydrothermal process are much more homogeneous and have smaller grain size, which is helpful to obtain Li4SiO4 pebbles with small grain size. Li4SiO4 pebbles were obtained by sintering the green bodies of pebbles at 800 °C for 4 h. The experimental results show that the Li4SiO4 pebbles have high phase purity, abundant pore structure, small grain size (a.v 0.67 μm) and high crush load (a.v 38.7 N). It indicates that the Li4SiO4 pebbles are expected to show favorable tritium release behavior and thus may be promising tritium breeding materials for fusion reactor blanket.